Double-stud walls have been regarded as a simple to build, low-cost, high-performance solution since the energy crisis in the 1970’s.  (See our blog post The Double-Stud Wall Simplified: Low-Cost High Performance, and free CAD details)  Pack them right, meaning 3.8 to 4.2 lbs/cubic foot of cellulose, 2.5 lbs/cf for fiberglass or wood fiber – and as Jesse Thompson of Kaplan Thompson Architects presented at BuildingEnergy 17, as a minimum requirement, add a vented rain screen so  they have a chance to dry outward.

Since we want to build these walls as economically as possible – when does adding INTELLO Plus make sense to maintain acceptable risk?

What’s Acceptable Risk?

In Monitoring of Double-Stud Wall Moisture Conditions in the Northeast, Building Science Corporation (BSC) reported on a study of double-stud wall in Massachusetts without vapor control (ie only painted gypsum board). The study lasted for 3 years, which included 1 year when the building was unoccupied. It did show that with healthy Relative Humidity (RH) on the interior (40-50%) that the wall Moisture Content in all walls, insulated with foam and cellulose, were showing condensation. In the subsequent year, while this occupied, not-super-airtight house had a continuous exhaust fan running, and with very low interior RH as a result (20%s) – and the north-facing cellulose wall still showed MC over 20%. In the conclusion Kohta Ueno writes:

ASHRAE 160 criteria were applied to the monitored data; all walls failed (i.e., mold growth likely). However, when the walls were disassembled at the conclusion of the experiment, the sheathing and framing showed remarkably little evidence of wetting damage or mold growth. No visible mold growth was found, nor evidence of staining or water rundown. The damage was limited to some grain
raise of the interior surface of the OSB at the cellulose wall, and corrosion of fasteners.

475 has also previously discussed moisture risk per the old ASHRAE 160 standard in double-stud walls with both fiberglass and cellulose – Keeping Sheathing Dry in High-R Double-Stud Walls – a WUFI Study and Drive Safe, Build Safe.

New ASHRAE 160 and the Mold Growth Index

ASHRAE 160 has since been updated.  As stated by the USDA Forest Products Laboratory, Standard 160 has now:

…incorporated the “mold growth index,” first proposed by Viitanen and Ritschkoff (1991), which was used to quantify the amount of mold growth that occurs in laboratory tests under controlled temperature and humidity conditions. The mold growth index assigns an ordinal number between 0 (no growth) and 6 (very heavy and tight growth). The Viitanen model can calculate the mold growth index from outputs of hygrothermal simulations and incorporates time, surface temperature, surface relative humidity, and the material sensitivity class. Standard 160 now requires that the mold growth index, calculated from hygrothermal simulations, be less than 3 (the threshold for visible mold growth).

With this new and improved model, sheathing (plywood/OSB) is classified as medium sensitive to mold growth/damage and set threshold for Mold Growth Index (MGI) at 3.  475 asked Manfred Kehrer (WUFI developer /www.wufi.us) to run simulations based on this new criteria for five climates: Boston (5c), Baltimore (4c), Atlanta (3c), Miami (2c) and Seattle (4a). We used fiberglass on purpose as the lowest cost solution.

The graph above shows, that for all but Miami, the walls exceed the 3 MGI threshold without INTELLO in the first winter, and the walls never recover from getting damp. You can also see this when plotting M% of the OSB/insulation interface in Baltimore, it exceeds 18% for long stretches every winter (which is higher than we recommend) and even 20% which is the level where practically all building scientists would have concern. Shown in the graph below:

INTELLO Plus optimizes performance and insulation in double stud walls

With INTELLO Plus, these double-stud walls, with a vapor retarding exterior sheathing layer (OSB at 1-ish perms) covered with the SOLITEX MENTO actively vapor open WRB – lead to safe construction in all climate zones, and even make the Miami wall dryer (no more winter time cycling in climate zone 2).

This smart vapor retarder and airbarier also make sure that the wall performs as intended at it’s R-40+ value, as it encapsulated the fibrous insulation with airtightness on all 6 sides.Note that 4a climate zone (Marine) puts more stress on the assembly than even Climate zone 5 (Boston). This since the drying capability of the wall is reduces by the climate’s humidity levels. This is shown in the graph below, in which even with INTELLO Plus and some assumed construction moisture, it takes more than a year for the assembly to get below 3 and could be considered safe. As BSC pointed out in their double-stud wall research – one or two years of elevated MC is okay, and might only lead to raised grain and minor rust on screws/nails – cycling through such moisture levels every winter could cause further deterioration and thus leaving out INTELLO in such double-stud walls, would be taking a short cut that you could regret after a number of years.

Window Flashing That Lasts

At the sill-jamb intersection, window flashing must bridge three dimensions. EXTOSEAL ENCORS remain air and water tight, and solidly bonded to the substrate, even when stretched over these tough corners.

Windows are the weak link in your assembly. Along with doors, they amount to the largest holes in your envelope.  To ensure that your building is air and water-tight, continuity between high-performance windows and your air barrier/WRB is essential. We’ve talked a lot about how to ensure air barrier continuity at windows, but equally important is ensuring that water can’t get into your building.  EXTOSEAL ENCORS, because of its flexibility, durability, air- and water-impermeability, and guaranteed lasting performance, is far and away the best choice for window flashing.

Well-executed window flashing that is continuous with your weather-resistant barrier is critical to creating a drainage plane for excess water. Because glass is highly waterproof, rain that hits the window will end up on the sill. For this reason, sills need to have the proper pitch to ensure easy drainage of rainwater. This is especially important for high-performance buildings, in which windows are set deeper into the assembly for the purposes of minimizing thermal bridging and accommodating more insulation.  And once water hits the sill, it needs to run off, not leak into the building or seep through the sill.

EXTOSEAL ENCORS: Long-lasting, airtight, waterproof and flexible

The flexibility of EXTOSEAL ENCORS means you don’t have to worry about the integrity of your water-tight flashing pan being compromised at challenging corners and junctures.

The EXTOSEAL ENCORS window flashing system is a highly flexible tape with acrylic-modified butyl adhesive that will last for the life of your building.  Upon application, EXTOSEAL ENCORS can be folded down over and connected to the WRB, ensuring a continuous air and water barrier from WRB to window. (It’s important not to cover the WRB more than about an inch, because EXTOSEAL ENCORS is vapor closed, and you don’t want to diminish the outward drying potential of your vapor-open WRB. And your WRB should definitely be vapor-open!) ENCORS can also be taped up into the window frame, ensuring a continuous drainage plane from window to sill to WRB using just a single piece of tape. If the sill is an uneven surface – masonry, for instance – TESCON primer can be used to ensure a seamless, watertight connection.

EXTOSEAL ENCORS is particularly useful because of its flexibility. It can be especially difficult to flash windows at the corner where the sill meets the jamb – a place in which the flashing material has to stretch over three dimensions.  Typical peel-and-stick flashing can’t handle this multi-dimensional stretching, so multiple strips have to be used – creating the potential for gaps, which can lead to air and water leakage and damage the sill. Because of their great flexibility and multi-release strips, EXTOSEAL ENCORS performs particularly well at these challenging corners. Your flashing pan should extend 4-6” up the jambs, so flexibility is key to ensuring continuity at these points. And for windows set deeper into the assembly, strips of EXTOSEAL can be layered shingle-style over one another to ensure continuity of the drainage plane from window to sill to WRB.

EXTOSEAL ENCORS technical specs:

• Acrylic modified butyl adhesive (butyl rubber modified with acrylate) is accelerated age-tested to last 100 years
• Tape is self-bonding under the effect of heat
• Application temperature range: 15F to 95F (-1oC to 35C)
• Once bonded, adhesive performs from -4F to 176F (-20C to 80C)
• Feature a highly flexible carrier foil with low restoring forces, allowing it to be stretched over frame corners (eliminates the need for multiple strips and provides further insurance against water ingress)
• Are completely watertight and block dampness
• Bond to wood, hard/high density plastic, metal, concrete, OSB, plywood, fiberboard, and ProClima membranes without a primer; primer recommended for bonding to uneven substrates such as concrete, brick, foamglass, and some OSB.
• Self-seal around screw and nail holes
• Are fully vapor-closed
• Come in widths of 6, 8, and 12″ for different window depths (though strips can be layered shingle-style for deep-set windows); all are 20m (65′ 7″)
• Feature three release strips for easy application over window frames, sills, and down to your WRB/exterior sheathing
• Bonds should not be subjected to tensile strain after application.

Ensuring Air Barrier Continuity Around the Entire Window

Once the EXTOSEAL ENCORS flashing pan has been installed, exterior window components can be overlaid, and you can be confident in your window’s air and water-tightness.

For the other three sides of your window, it’s also important to ensure continuity between the WRB and the window frame.  Contega EXO, a vapor open, air-tight, and water-tight tape, ensures that your window frame is continuous with the WRB, further preventing air and water intrusion into the assembly.  We recommend pre-taping your window frames before inserting them into the RO so that they can be easily attached to your WRB.

With solid acrylic adhesives that are waterproof and become stronger with time, these Pro Clima tapes are the best way to ensure that these challenging connections will remain robust and water tight for the life of your building.  So for difficult intrusions like windows, make sure to choose products that will ensure a high level of building performance for decades to come.

EXTOSEAL ENCORS can serve other purposes in your assembly as well.  ENCORS can be used to join wood panels to smooth concrete surfaces, and to bond wood fiber roof panels to one another or their adjoining structural elements.

Still need more info? Check out the EXTOSEAL ENCORS technical specs and application guide.

What exactly do we mean by high-performance building?  What are some of the obstacles to building this way?  And when compromises have to be made, how can we make cost-effective choices and still construct a high-performance, low-energy, and maybe even Passive House building?

In this presentation, we talk about the 6 key characteristics of high performance buildings, and how you can achieve these performance standards without increasing project costs.  Truly high performance or Passive House certified projects have gone from being an idealistic aspiration to a tangible reality in less than a decade. Enough time has passed to have examples, stories, and data to reflect on the first generation of these buildings and learn from their example. High Performance Gets Real is a series of case studies about the methods, materials and successes.

Watch the 30 minute presentation video below:

More 475 presentations available on demand:

• High Performance Historic Masonry Retrofits
• Notes From New York: Lessons from a Growing Market

A little housekeeping goes a long way.

We sell Pro Clima tapes because they are incredible products. They promise long-term airtightness that will last for 100 years, are highly flexible to stay airtight as your building moves and settles, and the solid acrylic adhesive involves no solvents, is moisture-tolerant, and is easy to apply. We could go on…

But key to the success of Pro Clima tapes is that they are able to fully adhere to the desired surface. If that surface is rough or uneven, or if it’s covered in construction debris, dust, and dirt, then the tape won’t be able to form an airtight bond. If the surface to which you’re taping isn’t airtight, then all bets are off. Also, the surface cannot be made of the same silicone that comprises Pro Clima’s backing strips and release paper… or it will release, as designed.

So how do you deal with these challenges to ensure that your adhesion is optimal, and that your building enclosure is fully airtight? With a little bit of extra care and attention, you can easily ensure the long-term performance and the permanent airtightness of your assembly.

Ensure a Clean, Dust-Free Taping Surface

Pro Clima tapes will stick to dust, but dust isn’t airtight. Dusty window corners will compromise the effectiveness of the tapes.

Job sites can be messy. Construction generates a lot of dust and debris, and buildings-in-progress are subject to weather and exposed to the elements. The solid acrylic adhesive in Pro Clima tapes bond to almost anything – and that means that, if you tape to a surface covered in dust and dirt, dust and dirt are exactly what your tape will adhere to. And dust is not airtight. This will lead to incomplete adhesion between the tape and the intended substrate, and can significantly compromise the airtightness of your building enclosure.

Silicone, grease, and other slick fluids can also reduce the effectiveness of the tape.  These materials drastically reduce the surface energy of the substrate.  Surface energy is the sum of the small intermolecular forces that make bonding possible – so by reducing the surface energy of your surface, silicone or grease decrease the effectiveness of the bond.

But a little housekeeping goes a long way. Simply brushing the dust and small particles off of the substrate, or removing any grease, before taping can increase the effectiveness of the tape dramatically. Pay careful attention to corners, where dust can pile up and be trapped. Wiping with a damp cloth to ensure that the surface is as clean as possible will further enhance the effectiveness of the bond between the tape and the substrate. Just make sure the surface is dry before taping.

Use Primer on Uneven or Porous Substrates

Pretreating porous or uneven surfaces like wood or masonry with TESCON PRIMER RP ensures a smooth, airtight substrate for Pro Clima tapes.

Sometimes, even a clean surface isn’t ready for taping.  Surfaces that are rough, cracked, uneven, or porous – like brick, masonry, OSB, and foam sheathing – are riddled with gaps that can serve as little conduits for air.  Even if these materials themselves are airtight, their rough surfaces preclude an the formation of an airtight bond to tapes.

In these situations, TESCON PRIMER RP works wonders.  Priming the surface creates a smooth, sticky, airtight substrate to which Pro Clima adhesive will easily form a lasting bond. Once TESCON PRIMER RP has been applied, you can immediately tape to the primed surface – no need to allow drying. The integrity of the bond between tape and substrate is essential to long-term airtightness – so when taping to rough surfaces like these, TESCON PRIMER RP can be make a decisive difference in building performance.

CONTEGA Adhesives: Attaching membranes at building joints

Applying two strips of CONTEGA MULTIBOND offers extra protection on particularly rough surfaces, and can help to mitigate the unevenness of the substrate.

Attaching membranes to adjacent surfaces at building joints can be tough, because the connection between the membrane and the building element at the joint must be airtight.  This is especially challenging if the surface is rough. Caulk will likely be the best solution – in which case we suggest either CONTEGA HF or CONTEGA CLASSIC, for a more traditional application of liquid-applied. For more on the similarities and differences between the two caulks, take a look over here.  ProClima also offers a unique alternative solution with CONTEGA MULTIBOND. If the membrane you’re attaching is vapor-closed and impermeable, caulk would never be able to fully dry. CONTEGA MULTIBOND is a pre-cured line of adhesive that is activated by pressure, just as with adhesive in Pro Clima tapes. This allows for a flexible, instantly bonding joint adhesive suitable for interior and exterior use.

The strong bond forms instantly when pressure is applied.

Because of its malleability, CONTEGA MULTIBOND can fill the cracks on an uneven surface for an airtight bond.  For particularly rough surfaces, two strips can be applied to one another for extra protection.  As always, it’s important to ensure that your surface is clean and dust-free before applying CONTEGA MULTIBOND.  Once pressure is applied, CONTEGA MULTIBOND instantly bonds to both the substrate and the membrane – ensuring immediate and long-lasting airtightness.

CONTEGA MULTIBOND can be applied to a wide range of substrates, including plaster, concrete, masonry, roughly sawn or painted wood, OSB, and rustproof metal.  Although priming the surface isn’t necessary in most cases, an adhesion test can tell you whether pre-treating the surface with primer could increase the stability of the system.

Sawdust isn’t airtight – so taping to it won’t be airtight, either!

MULTIBOND can be applied in temperatures as low as 5°F (-15°C), and once applied will perform from -40°F to 212°F (-40°C to 100°C).  Because summer roof temperatures in hot climates can reach as high as 75°C, that performance range is important.

Summing It Up

Pro Clima tapes are powerful tools for ensuring the long-term airtightness of your building. Investing a little bit of extra effort in making sure that they are applied properly can pay huge dividends in building performance and energy savings.  That means ensuring that your taping surface is clean, free of dust, grease and silicone, and that your substrate itself is airtight. Do yourself this solid, and your blower door test will thank you.

The official plaque of the Perfect Building is reclaimed wood, with live words growing in a mix of moss and lichen. The moss will grow and change along with the building.

This is a moment of mixed emotion at 475.   We are sad to witness the death of Passive House but excited to steal its best aspects and make our own proprietary standard – The Perfect Building™, administered by our very own Best Practices Institute©.

The Best Practices Institute© is a paradigm shift in the QA/QC delivery of integrated optimization.  The Declare Label is obsolete, all natural batt and board insulations are antique, state-of-the-art high-efficiency heat recovery ventilation systems are useless, and careful energy optimization is ridiculous.  Today, a new generation of consumers simply demand: “It just has to be perfect!”.   We heard the sorrowful cries and are responding.

But you ask, wasn’t Passive House perfect enough?   After all, didn’t many people think it was too rigorous?   The Pretty Good House made some pretty good houses – but really, do you strive to send your children to a pretty good doctor or a  pretty good school?   That wasn’t the answer. But still, was it too rigorous?  Doubters proclaimed that the airtightness was just too difficult, the components too expensive, industry untrainable.  Passive House, they said, can’t compete!

Elrond’s last know location

WRONG!  We know it was the lack of rigor that killed it.   Others were on the case.  Named “The Elrond Standard” by Lloyd Alter after its originator Elrond Burrell, this new standard clearly demonstrated that Passive House had its limitations.  What else was needed?   According to Elrond, (who, it should be noted, went into hiding in the southern hemisphere around the time of publication of his new standard), the building must also be made from low-embodied energy materials, non-toxic materials and be located in a walkable neighborhood.  Damn, that’s good.

But we soon realized that it wasn’t perfect.  In our local Brooklyn dialect our customers would clarify: “My building just needs to be f#cking perfect, a##hole!”   Clearly Passive House’s days were numbered. So, in a way that would make New York’s leading citizen proud, we acted:  nimbly, perhaps criminally, opportunistically and certainly  remorselessly – and we founded The Best Practices Institute©, that ensures every building will be a Perfect Building™.

Yet in formulating the The Best Practices Institute©, and the Perfect Building Standard™, we sought not to simply be additive, but instead be destructive.  Genius!  We stepped back to a pre-Hegelian state, then deconstructed – subsequently revealing that buildings post-structuralist  potential is possible – positing perfection.  The Best Practices Institute© had its mojo and it was based on the simplicity of the ingredients and the process.

Beard Insulation™ is a critical Perfect House™ component

There are only a few basic ingredients:

The happy home owner approaches the Perfect Building Standard™ home – disguised to perfectly blend in to its natural surroundings.

The process is even more simple.  Just take these ingredients and put them into our reclaimed HAL 9000.1,  (patent#004.7549743475434799743) and what comes out is The Perfect Building™, built perfectly™!  And unlike the Passive House Institute, USGBC, BREEAM, Living Future Institute, International WELL Building Institute, Norwegian Powerhouse, EnergyStar, R2000, Greenglobes, NAHB, Watersense, FSC, SFI, Greenguard, HPD, PHIUS+, Edge, Active house, Passivesolar, NZEB, Sentinelhaus, MinergieP, Darksky  – The Best Practices Institute© reserves the right to randomly change certification criteria depending on how much we like you.  So be nice!

Because you love sending us examples of the many creative and improvisational ways you end up using our handy high performance materials, this is a continuing series . See Part 1 and Part 2 of The Best of Off-Label Uses, and keep your images coming through on twitter, facebook, or instagram.

Vehicles of all types have become a recurring theme:

I repaired the rust holes on my rear truck bed panel. With tescon from 475. now I need to spray paint it silver. @foursevenfive pic.twitter.com/MHQwnA5bUw

— Robert Swinburne (@RobertSwinburne) March 4, 2017

A nice German delivery truck deserves a nice German tape. In this case EXTOSEAL FINOC.

Now here’s a pretty tape job! Score.

Ah…. here’s our favorite transportation mode. Glad we can be of assistance.

On to houseware and personal effects

Hey, when you gotta stay dry… Tescon Vana’s a good choice

Hopefully now that couch is going to last another 50 years.

A boot! (Not mocking the Canadian accent, just remarking about this well-patched footwear.)

Who doesn’t like a koozie made out of waterproof airtight building membranes and tapes and sheep’s wool insulation? #proclima @foursevenfivedotcom @havelockwool1 @threesbrewing

A post shared by Craig Toohey (@ctoohey) on Apr 6, 2017 at 2:08pm PDT

On the job…

When your glass door shatters, you still need a good air barrier.

A post shared by Jason Endres (@passive_jay) on Nov 19, 2016 at 2:03pm PST

For the theatre crowd, hey look: it’s New York’s very own Joe’s Pub sealing up an old, leaky accordion with TESCON INVIS. It’s Gaffer’s tape you use when you never want to remove the tape ever again. 

Wait… is that a… PRESSFIX acting as a shim beneath a big beam? Why yes it is. VERY OFF-LABEL, IN FACT OFF THE ROCKER.

And finally we have. Um… It’s ah….. Well, I’ll just let them tell you (see quote below)

I finally got a chance to look at your sealing tape with our microscope that see things that scatter light (like fog) and things that are fluorescent (like the blacklight posters of our misbegotten youth).  It also looks at only one XY plane at at time, but by changing focus position one can get the equivalent of an XY and Z image.  Green is the scatter and red is the fluorescences.   There’s approximately 700 micron across (1 million microns per meter) sized divots spread across the tape.  In uncompressed tape they kind of look like little bubbles, with a high scattering cap at the bottom.  In compressed tape they look much more disorganized and the walls sometime have flattened to the glass slide they’re taped too.  In each image, the large panel is looking down on the tape from above, but only seeing the plane indicated by the green line in the side panels.  Each side panel is the cross-section along one of the X or Y lines (in yellow) in the central panel.

I’m surprised how not tacky the tape is until its compressed.  Being a kayaker and always looking for better ways to repair holes in boats on the water I actually compressed a piece against a clear plastic dish while it was under water and it stuck like crazy.   

That’s it for now!
Send your shots and join us next time: twitter, facebook, or instagram.

The Smart Wall is an essential part of the Smart Enclosure and represents a return to fundamental principles of building science.  We leverage the basics of natural principles with highly selective technological innovation and manufacturing – working in harmony with nature, not in opposition.  The Smart Wall system is made of efficient, resilient and sustainable products, including HAVELOCK WOOL sheep’s wool insulation, Pro Clima membranes such as INTELLO Plus, and GUTEX exterior insulation board – resulting in buildings that are better for people and for the planet.

So what are key attributes of the Smart Wall assembly?

• Natural Insulation Materials.  Continuous GUTEX Wood fiberboard insulation and HAVELOCK WOOL sheep’s wool cavity insulation insulation are non-toxic, zero-VOC high-performance materials.
• Vapor Intelligence.  Pro Clima INTELLO Plus is a zero-VOC, vapor intelligent membrane that builds drying reserves by responding to changing conditions of vapor drive and moisture concentrations – and ensuring the long-term health of your building by preventing moisture loading of the building assembly.
• Airtightness.  An airtight enclosure is essential – providing comfort, energy efficiency and protection against moisture damage – to high performance building.  Pro Clima membranes and tapes provide long-term building airtightness.
• Comfort and Indoor Air Quality.  A vapor-intelligent, airtight assembly that utilizes natural materials can guarantee a high level of indoor air quality and occupant comfort. The Smart Wall resists mold growth, eliminates concerns about off-gassing and VOCs, and is very effective at sound attenuation – all contributing to a healthy and comfortable indoor environment.

The Smart Wall Assembly Breakdown

SMART WALL ASSEMBLY

Moving from interior to exterior, the Smart Wall consists of:

• Interior finish
• Furring strips forming a service cavity (with optional additional sheeps’ wool insulation) – for wiring, outlets and other services.
• INTELLO Plus interior air barrier and vapor-intelligent membrane
• Framing with HAVELOCK WOOL insulation,
• Structural sheathing (from boards to exterior grade gypsum board)
• Continuous GUTEX wood fiberboard exterior insulation and WRB
• Furring strips for back-vented rainscreen.
• Exterior siding rainscreen

The Smart Wall is the ideal solution for low-carbon, high-performance wall construction.  Let’s break it down further.

Smart Wall Component Breakdown:

HAVELOCK WOOL: Natural Insulation

Wool is just about as natural as an insulation material can get. Havelock Wool, from New Zealand sheep, is a durable, carbon-negative, all-natural, and very high performing form of insulation. Some of the benefits of wool insulation include:

• Havelock Wool is a safe, all-natural insulation material. It is also baby-tested and approved.

  Moisture Control.  Wool insulation is capable of absorbing up to 35% of its weight in moisture, and manages moisture levels against 65% relative humidity.
• Toxin Sequestration.  Wool binds permanently to formadehyde, sulfur dioxide, and nitrogen oxides, sequestering them from the air that you breathe and improving the health of the indoor environment.
• Chemical free.  No dyes, toxins, or other chemicals are added to this virgin, untreated wool product.
• Fire Resistance.  Wool extinguishes after smoldering, limiting the spread of fire. This is in great contrast to the high flammability of petrochemical-based insulation materials.
• Easy Installation. Wool is available in batts, or can be blown-in behind the interior air membrane like cellulose insulation.
• Long-lasting Performance.  Wool resists mold growth, and won’t sag over time, meaning that your R-values and healthy indoor air quality will be maintained over the life of the wall assembly.
• Zero-waste.  Wool can be reused or composted after use, mitigating concerns about the life-cycle impacts of building materials.

Havelock Wool comes in batt or loose-fill (not dense-pack). Wool is naturally a straight fiber, able to hold its form without settling. The wool targets 0.5 lbs/ft³ whereas cellulose dense-packed would be 3.5 – 4 lbs/ft³. Wool is a safe, comfortable, and natural alternative to synthetic insulation. So give your house the sweater it deserves with Havelock Wool.

GUTEX: Carbon-Negative, Triple-Duty Performance

Guys at Kaplan Thompson enjoying working with GUTEX in Maine

GUTEX is an ideal product: exterior sheathing that serves as a WRB, a vapor-open, airtight layer, and additional building insulation. Some of the benefits of GUTEX include:

• Vapor open and weather-resistant.  At 44 perms, GUTEX wood fiber boards are highly vapor-open, allowing outward drying and preventing moisture build-up in your wall assembly.
• Noise attenuation.  GUTEX is dense, and provides additional noise attenuation to ensure occupant comfort.
• High thermal lag.  Because of its density and high specific heat capacity, GUTEX boards heat up slowly. This keeps the building cool on hot days, and comfortable at night.
• Net carbon sink. GUTEX is made from post-industrial recycled wood chips mixed with shavings of spruce and pine. Because trees take carbon from the atmosphere, GUTEX is a carbon-negative product.
• Low impact dry production process. The unique dry-production process for GUTEX increases the density (and therefore performance) of the boards while reducing the energy required for their construction.
• Environmentally friendly disposal.  GUTEX can be re-used at the end of their life in your building, can be burned as fuel, or, because they are biodegradable, will easily break down.

GUTEX wood fiber board serves numerous roles in your building assembly and ensures long-term building performance.

PRO CLIMA Membranes: Vapor Intelligent Airtightness

The vapor variability of INTELLO Plus ensures the maximum drying potential of your wall assembly.

Pro Clima membranes are the lynchpin of our approach to airtightness.  INTELLO Plus, our recommended interior membrane, ensures long-term airtightness and vapor intelligence. This vapor-variable membrane is responsive to interior relative humidity levels to ensure that moisture is able to leave the assembly.  As Alex Wilson has written on BuildingGreen, “Smart Vapor Retarders: Not Just Your Grandmother’s Poly“.

• Truly airtight with a tested airtightness of 0.00005cfm/ft2 per ASTM E2178.
• The strongest and most intelligent vapor curve.  Providing unsurpassed protection against moisture damages.
• Durable: able to take a beating on the job site.  See our tear test.
• Complete system: of gaskets and connecting components such as tapes, caulks – tested to perform best.
• Fully integrated with other components: like window penetrations and pipe penetrations.
• Declare Label recognized by the International Living Future Institute.

INTELLO Plus with service cavity

Pro Clima membranes (and the tapes that complement them) are the best way to ensure permanent building airtightness without risking the accumulation of moisture that can lead to the growth of mold and rotting structural elements.

Let’s Build A Truly High-Performance Wall, Together

We believe the Smart Wall, consisting of Pro Clima membranes, Havelock Wool insulation, and Gutex wood fiber board, exemplifies what is possible. A sustainable future means re-balancing our respect for natural processes and our technological innovations.

So, make the Smart Wall choice.  Contact us to get started today.

Archigram’s A Walking City, 1964: boundless energy & engineering anyone?

For thousands of years buildings were made with a keen regard for nature and historically building science was intimately attuned to natural phenomenon.  Then, the 20th century builders, with giant resources of energy and rapid scientific advancements tried to conquer the vagaries of nature.  Natural solutions were ignored and flaunted – they made up, down, and down, up – if they felt like it.  And any unintended bad consequences would be answered with yet more engineering and power.  It has been brute force all the way down – landing us in a dystopian landscape.   Today our traditional buildings are so chemical and energy dependent, they are a leading cause of our environmental catastrophe. Their resulting pollution has acidified the oceans and warmed the climate to such an extent that we imminently face massive species die-offs.  And we’re poisoning everything – all species, ourselves and our families – in the process.  Soon there will be more plastic than fish in the oceans!

Our poster child of industry run-amok is spray foam insulation. We’ve written about many of the problems in our Foam Fails series.  Spray foam is the cornerstone of building enclosure failure. Fortunately there is growing industry understanding that spray foam is an unreliable, toxic, and expensive approach which is based more on Madison Avenue marketing than common sense. We say: Less is Best.

Then What?

The answer to our predicament today, is not to throw off technology and return to the Primative Hut, but instead, is to synthesize our understanding of natural systems, and selectively use technology that provides great benefits with manageable environmental impacts.

Lloyd Alter, writing in Treehugger, notes that our current obsession with energy efficiency and high-performance, as realized in the Passive House Standard, is not enough.  Yes, efficiency and comfort are critical to our sustainable future, but to ignore other critical factors may likely result in just another techno trap.    Lloyd proposed “The Elrond Standard” – in reference to Elrond Burrell’s formulation that eco-friendly building must, in addition to reaching Passive House performance, also be: made of materials that are non-toxic and of low embodied energy; and the building should be located in a walkable neighborhood.  We couldn’t agree more.

Focusing on what we do at 475 – providing critical knowledge and components for high performance enclosures and buildings – we know we can make smarter choices today.  The smarter choice we offer is what we call the Smart Enclosure.  The Smart Enclosure is an assembly system made of non-toxic materials, with low embodied energy, that creates long-lasting construction – and delivers comfort, health, and efficiency without rot, mold, or other maintenance and health headaches.

The Smart Enclosure

The Smart Enclosure is a return to fundamental principles of building science.  Then we leverage the basics of natural principles with highly selective technological innovation and manufacturing – working in harmony with nature, not in opposition.  The Smart Enclosure acknowledges its profound relationship with the outside environment and the occupants within.   This system is made of efficient, resilient and sustainable products, including HAVELOCK WOOL sheep’s wool insulation, Pro Clima membranes such as INTELLO Plus, and GUTEX exterior insulation board – resulting in buildings that are better for people and for the planet.

So what are key attributes of the Smart Enclosure assembly?

• Natural Insulation Materials.  Continuous GUTEX Wood fiberboard insulation and HAVELOCK WOOL sheep’s wool cavity insulation insulation are non-toxic, zero-VOC high-performance materials.
• Vapor Intelligence.  Pro Clima INTELLO Plus is a zero-VOC, vapor intelligent membrane that builds drying reserves by responding to changing conditions of vapor drive and moisture concentrations – and ensuring the long-term health of your building by preventing moisture loading of the building assembly.
• Airtightness.  An airtight enclosure is essential – providing comfort, energy efficiency and protection against moisture damage – to high performance building.  Pro Clima membranes and tapes provide long-term building airtightness.
• Comfort and Indoor Air Quality.  A vapor-intelligent, airtight assembly that utilizes natural materials can guarantee a high level of indoor air quality and occupant comfort. The Smart Wall resists mold growth, eliminates concerns about off-gassing and VOCs, and is very effective at sound attenuation – all contributing to a healthy and comfortable indoor environment.

The Smart Enclosure starts with a Smart Wall that embodies these qualities.   Let’s break the assembly down.

The Smart Wall Assembly Breakdown

SMART WALL ASSEMBLY

Moving from interior to exterior, the Smart Wall consists of:

• Interior finish
• Furring strips forming a service cavity (with optional additional sheeps’ wool insulation) – for wiring, outlets and other services.
• INTELLO Plus interior air barrier and vapor-intelligent membrane
• Framing with HAVELOCK WOOL insulation,
• Structural sheathing (from boards to exterior grade gypsum board)
• Continuous GUTEX wood fiberboard exterior insulation and WRB
• Furring strips for back-vented rainscreen.
• Exterior siding rainscreen

The Smart Wall is the ideal solution for low-carbon, high-performance wall construction.  Let’s break it down further.

Smart Wall Component Breakdown:

HAVELOCK WOOL: Natural Insulation

Wool is just about as natural as an insulation material can get. Havelock Wool, from New Zealand sheep, is a durable, carbon-negative, all-natural, and very high performing form of insulation. Some of the benefits of wool insulation include:

• Havelock Wool is a safe, all-natural insulation material. It is also baby-tested and approved.

  Moisture Control.  Wool insulation is capable of absorbing up to 35% of its weight in moisture, and manages moisture levels against 65% relative humidity.
• Toxin Sequestration.  Wool binds permanently to formadehyde, sulfur dioxide, and nitrogen oxides, sequestering them from the air that you breathe and improving the health of the indoor environment.
• Chemical free.  No dyes, toxins, or other chemicals are added to this virgin, untreated wool product.
• Fire Resistance.  Wool extinguishes after smoldering, limiting the spread of fire. This is in great contrast to the high flammability of petrochemical-based insulation materials.
• Easy Installation. Wool is available in batts, or can be blown-in behind the interior air membrane like cellulose insulation.
• Long-lasting Performance.  Wool resists mold growth, and won’t sag over time, meaning that your R-values and healthy indoor air quality will be maintained over the life of the wall assembly.
• Zero-waste.  Wool can be reused or composted after use, mitigating concerns about the life-cycle impacts of building materials.

Havelock Wool comes in batt or loose-fill (not dense-pack). Wool is naturally a straight fiber, able to hold its form without settling. The wool targets 0.5 lbs/ft³ whereas cellulose dense-packed would be 3.5 – 4 lbs/ft³. Wool is a safe, comfortable, and natural alternative to synthetic insulation. So give your house the sweater it deserves with Havelock Wool.

GUTEX: Carbon-Negative, Triple-Duty Performance

Guys at Kaplan Thompson enjoying working with GUTEX in Maine

GUTEX is an ideal product: exterior sheathing that serves as a WRB, a vapor-open, airtight layer, and additional building insulation. Some of the benefits of GUTEX include:

• Vapor open and weather-resistant.  At 44 perms, GUTEX wood fiber boards are highly vapor-open, allowing outward drying and preventing moisture build-up in your wall assembly.
• Noise attenuation.  GUTEX is dense, and provides additional noise attenuation to ensure occupant comfort.
• High thermal lag.  Because of its density and high specific heat capacity, GUTEX boards heat up slowly. This keeps the building cool on hot days, and comfortable at night.
• Net carbon sink. GUTEX is made from post-industrial recycled wood chips mixed with shavings of spruce and pine. Because trees take carbon from the atmosphere, GUTEX is a carbon-negative product.
• Low impact dry production process. The unique dry-production process for GUTEX increases the density (and therefore performance) of the boards while reducing the energy required for their construction.
• Environmentally friendly disposal.  GUTEX can be re-used at the end of their life in your building, can be burned as fuel, or, because they are biodegradable, will easily break down.

GUTEX wood fiber board serves numerous roles in your building assembly and ensures long-term building performance.

PRO CLIMA Membranes: Vapor Intelligent Airtightness

The vapor variability of INTELLO Plus ensures the maximum drying potential of your wall assembly.

Pro Clima membranes are the lynchpin of our approach to airtightness.  INTELLO Plus, our recommended interior membrane, ensures long-term airtightness and vapor intelligence. This vapor-variable membrane is responsive to interior relative humidity levels to ensure that moisture is able to leave the assembly.  As Alex Wilson has written on BuildingGreen, “Smart Vapor Retarders: Not Just Your Grandmother’s Poly“.

• Truly airtight with a tested airtightness of 0.00005cfm/ft2 per ASTM E2178.
• The strongest and most intelligent vapor curve.  Providing unsurpassed protection against moisture damages.
• Durable: able to take a beating on the job site.  See our tear test.
• Complete system: of gaskets and connecting components such as tapes, caulks – tested to perform best.
• Fully integrated with other components: like window penetrations and pipe penetrations.
• Declare Label recognized by the International Living Future Institute.

INTELLO Plus with service cavity

Pro Clima membranes (and the tapes that complement them) are the best way to ensure permanent building airtightness without risking the accumulation of moisture that can lead to the growth of mold and rotting structural elements.

Let’s Build A Sustainable Future, Together

A sustainable future means re-balancing our respect for natural processes and our technological innovations.  We believe the Smart Wall, consisting of Pro Clima membranes, Havelock Wool insulation, and Gutex wood fiber board, exemplifies what is possible.   The Smart Enclosure can ensure long-lasting, high-performance buildings that are healthy for occupants – and for the planet.

So, make the Smart Wall choice.  Contact us to get started today.

credit: uscountryproperties.com

Spray foam throws off two forms of toxic poison:  off-gassing of the volatile organic compounds and uncured chemical dust.

Spray foam is a two-component chemical system: Part A and Part B.  When the chemicals are properly prepared and precisely mixed, under the right site conditions, the chemicals will have a complete reaction eventually and become inert, ceasing to off-gas.

But off-gassing will occur indefinitely if the chemicals don’t have a complete reaction because they are not properly prepared, or precisely mixed or the site conditions are not right.   Even when the application of the chemicals is done perfectly, it will off-gas during the curing process, which takes time.   And while the chemicals are being sprayed with this onsite manufacturing process, there is certainly a lot of off-gassing.

When the foam is cut and trimmed as it hardens dust can be generated that contains unreacted chemicals.

Off-gassing spray foam and spray foam dust can be very dangerous.  The installation worker is not wearing a hazmat suite with full face and respirator protection because it’s comfortable.  It’s potentially dangerous for the occupants too.  Occupants must stay away from the building while it cures and/or the dust remains.  And, even assuming you’ve cleaned the dust, if the chemicals don’t cure completely, the occupants may end up staying away forever.

So let’s look at the dangers of off-gassing and spray foam dust – for the construction workers and the occupants.  And more reasons why Foam Fails.

Why Is Off-Gassing Foam & Foam Dust Dangerous?

The short answer is that it’s toxic!  In Why Foam Fails. Reason #1: Dangerous Toxic Ingredients noted that the high level of toxicity is well known:

The isocyanate [Part A] is typically formed from methylene diphenyl diisocyanate or MDI.  MDI is a known allergen and sensitizing toxicant.   From the EPA:

“Diisocyanates are well known dermal and inhalation sensitizers in the workplace and have been documented to cause asthma, lung damage, and in severe cases, fatal reactions.”

Once you have been “sensitized” from exposure to MDI, even the tiniest subsequent exposure can have severe health effects.

The catalyst for the reaction/curing is often an amine compound or lead naphthenate.    Amine is derived from ammonia.

From the Alliance for the Polyurethanes Industry:

“Many amine-based compounds can induce histamine liberation, which, in turn, can trigger allergic and other physiological effects, including bronchoconstriction or bronchial asthma and rhinitis.

Systemic symptoms include headache, nausea, faintness, anxiety, a decrease in blood pressure, tachycardia (rapid heartbeat), itching, erythema (reddening of the skin), urticaria (hives), and facial edema (swelling). Systemic effects (those affecting the body) that are related to the pharmacological action of amines are usually transient.  Typically, there are four routes of possible or potential exposure: inhalation, skin contact, eye contact, and ingestion.”

And if you are already a chemically sensitive person – as we say in Brooklyn: Fuhgeddaboudit!

David Marllow, at the CDC noted in 2012:   “The hazards of MDI are well-documented and their exposure limits have been established. However, the known hazards for spray polyurethane foam only take into account the first part of the mixture—the MDI.  The other half of the mix has not been studied for worker safety. It is a chemical question mark with no toxicology or health information. This part contains amines, which act as a catalyst; glycols—blowing agents that react with the foam; and phosphate, a flame retardant. This half of the spray polyurethane foam equation raises several questions…”

When homes are damaged with uncured spray foam, often the tell-tale sign is a bad odor.  Too often the situation is described as an odor problem.  But it’s not really.  Would you look at a corpse of a murder victim and say the problem was that the body smelled?  Yes, the smell may be unpleasant, but the odor is just the canary signalling the potential danger.  The danger is a potential poison problem.

Off-Gassing & Dust During Spray Foam Installation

During installation all occupants should be out of the building entirely.  The only construction workers onsite should be the spray foam installer in a full hazmat suit with face protection, gloves, boot covers and a dedicated supply air respirator.   If it is a big job site it needs to be properly partitioned to separate unprotected workers from the off gassing.  The job site needs to be properly ventilated.

If these basic guidelines are not followed there can be disastrous health results.   Too often families are not told to leave their home during the installation process and have acute adverse effects.  As described to GreenBuildingAdvisor by Keri Rimel:

“The contractor, Deruiter Insulation, didn’t keep us out of the house at all. Our children were there when they were shooting it. We were visiting the job site, and we had meetings in the bedroom as the guy in a haz-mat suit was spraying. The Demilec rep was there on the job that day — Darren Butler from Demilec. He made a surprise visit just to tell us how great the insulation was, and how great Deruiter Insulation was. They did not ventilate at all. In fact all the windows were taped shut to keep the house warm for the next two weeks.

“Three days after they sprayed, my husband’s respiratory system shut down — his throat closed up. I thought, ‘We have a problem.’

Off-Gassing & Dust Immediately Following Spray Foam Installation

Not only must occupants and other workers stay off the jobsite during the spray foam installation but also immediately after.   The curing takes time and until it is completely cured there is dangerous chemical off-gassing happening.   The residual dust must be cleaned away before re-entry too.

So, assuming there is a complete chemical reaction of all the chemicals applied, when is it safe to re-enter the building?  Of course the answer is, it depends.  For example as the EPA notes:

When determining a safe re-entry time, take into consideration vulnerable populations such as children. Children may crawl, roll, or sit on surfaces (i.e., carpets and floors) and play with objects such as toys where chemical dust or residues may settle. Children with asthma are an especially vulnerable population.

The standard industry answer, per the EPA, under conditions where the chemicals fully react, appears to be that everyone should stay out for at least 24 hours, maybe up to 72 hours.  And the site should be well ventilated during this period too.

Indefinite Off-Gassing From Uncured Spray Foam

Family exiled to trailer after home becomes unlivable.

And then there are the semi and fully abandoned buildings.

When a spray foam application fails to fully react the off-gassing can continue indefinitely – forcing occupants to flee indefinitely, causing not only health problems but deep financial problems as well.

One family’s ordeal was the subject of a Canadian Broadcasting Corporation Marketplace segment.   After an attic spray foam job failed to cure, headaches, joint pain and swelling legs and feet resulted – sending the mother to the hospital.  The persistent off-gassing forced the family to live for months in a temporary trailer next to their poisoned home.  To make the home livable again they decided to remove the entire roof/attic structure from the house and rebuild an entirely new roof.

Another couple from Vermont reported to us – condensed for brevity here:

…We had a bad spray foam retrofit installation in 2016. We can’t live in the home now because I became sensitized to chemicals, likely isocyanates.  I developed asthma and photophobia, near non-stop headaches and nausea. I also have memory issues, as does my husband, and balance issues, which have gotten somewhat better but not completely better. I swept up the sanded foam particles that were on the stairs and in the hallway near our bed because the workers didn’t clean much at all. We also met with the contractor in the home and upstairs shortly after spraying and he said it’s okay to do that because the foam dries almost as soon as it’s sprayed.  We don’t know if all the foam is bad or just sections.  The contractor’s insurance has denied the claim due to pollution exclusion. We’ve been told it’s impossible to get 100% of foam out of rough timbers-main carrying beams. Humidity still causes health problems and strong odors and it still smells bad when the sun hits the building in warm/hot weather…

Jim Vallette, of the Pharos Project – introduces us to the story of Richard Beyer of East Lyme Connecticut.   Richard writes:

“A few years ago, I started taking Benadryl so I could sleep at night.  I could not sleep because my skin felt like it was on fire. I suffered major headaches, heart palpitations and breathing problems.  These symptoms began after we hired a company to manufacturer spray polyurethane foam (SPF) insulation in our house.  The installation failed badly.  Industry standards say their product is supposed to become “inert” after installation.  This was not the case in my home.  The SPF insulation emitted noxious odors and gases, shrunk, cracked, disappeared and literally exploded in the middle of the night.  It never stopped off-gassing. Problems escalated from bad to worse.  I started investigating the products more.  What I found was extremely disturbing.”…

These are devastating and entirely avoidable problems – brought on simply because people wanted to insulate their homes.

Avoid The Potential Problems

What’s the problem?  The industry and government regulators claim ignorance – we paraphrase: “We don’t know what is causing what.” or “The scientific evidence isn’t conclusive”.  Sprayfoam.com notes: “the potential for off-gassing of volatile chemicals from spray polyurethane foam is not fully understood and is an area where more research is needed.”  The CDC, EPA and OSHA all say much more research is needed to understand what is going on also.

To add to the uncertainty, the chemical companies are quick to blame the installers.   They say, “It’s not the chemicals – it’s improper installation!”  This industry mantra reminds us of the NRA’s chant – “Guns don’t kill people, people kill people.”  To extend the metaphor, as expert Bernard Bloom notes in the CDC Marketplace segment – you’re playing Russian Roulette with your property when you decide to spray foam it.

Do you feel lucky?

What are the chances?   When asked how often they get odor complaints, GBA quotes a chemical manufacturing representative responding: “When we looked at the numbers, it appears to be less than one tenth of one percent…”  That’s a chance of about 1 in 1,000 – from the industry’s mouth.  Is the industry representative understating the number of incidents?  Probably.  So as Dirty Harry might say: “You’ve got to ask yourself, do you feel lucky?”

If you don’t want to play Russian Roulette with your home, we suggest you not use spray foam.  Less is Best.  There are safe, healthy, high-performance alternatives that run zero risk of poisoning the occupants.  Reach toward safe and natural high-performance building products.  Let’s make a healthier and less toxic world.

475 is excited to present this guest blog post by Brad Hankins, a designer-builder from Langley, WA. Long committed to sustainability, Brad knows the environmental benefits of high-performance construction. But Brad was also interested in understanding how quickly investments in energy efficient design pays for themselves, an important factor in convincing homeowners to jump on the high-performance bandwagon. After meeting Lucas Johnson, 475’s West Coast Representative, Brad decided to retrofit two of his cabins with INTELLO Plus – with enormous results. Now, he advocates for INTELLO in almost all new construction and retrofits.  

Brad’s powerful story speaks for itself:  

I’m A Builder, And I Advocate Using INTELLO Plus

I want to share my experience with the INTELLO Plus air barrier, how it dramatically enhanced the performance of my home, and why I now advocate for using it in as many buildings—new or retrofit—as possible.

I build small structures called “micro buildings,” which are less than 200ft2 – the cutoff for non-permitted, and therefore easily movable, buildings. I’ve determined that the most efficient dimensions for these buildings is 10’ x 16′. I have built a dozen of these now, including two for my own family. We heat them with modest electric baseboard heaters, about 1200W each.

My wife and I spend a fair amount of time in these buildings. But the first cold spell we had this year—over a week below freezing—left us in buildings that didn’t keep us warm. In theory, they are insulated to R-13 with Kraft-faced batts on the walls and an R-21 vented roof assembly. It was as tidy of an installation as possible with batts, but nonetheless we had terrible fiberglass dust and mediocre energy performance. I was disappointed, to say the least.

I worked on these buildings for about eight months during my spare time. Midway through the process, I met Lucas from 475 High Performance Building Supply and learned of some new products. Lucas is one of the most knowledgeable people I’ve ever talked with about building envelope performance. I was sold on the benefits of INTELLO Plus, SOLITEX MENTO, wool insulation—the works.

We had already installed the fiberglass batts, reused from a remodel, but we decided to install INTELLO over the batts on the interior of the building. My god, what a difference. We could immediately turn the heat down. The buildings were staying warm now.

And then came another cold spell, similar to the first. And we never had to turn the heat up. They performed amazingly—with no more dust, to boot.

The buildings were far more efficient, solely due to the installation of a simple, vapor-intelligent interior air barrier. Our electric usage after we installed the INTELLO dropped in half.

Because of this experience, I was intrigued by the idea of evaluating better building energy performance in terms of dollars saved. Sure, these products add to the cost of construction, and the average homeowner or builder doesn’t consider them necessary—if they know about them at all. But I wanted to know: if they use these products, will they save money? If so, how much? Ultimately, a new client of mine wanted to know: How long until the energy savings pays for the additional upfront cost of these products?

This isn’t really a fair question because there are many other advantages: no more mold and mildew, superior comfort, cleaner air, red list compliance, non-toxic and sustainable materials. But all of these benefits aside, I wanted to know how to promote these products solely on their merits regarding energy savings. Convincing homeowners that the investment will benefit their bottom line is key.

Enter the Whannell residence. The design was for a simple house: 1600 ft2 , single-level, slab-on-grade, 2×6 walls, vented attic space and prescriptive energy code design. The framing was set, and my client decided on a metal roof that we’ll install as well.

In talking about the roof system, we compared tar paper with SOLITEX MENTO 1000. This led to a conversation on siding and wall performance. After pricing out 30lb tar paper at $0.11/ft2 and MENTO 1000 at $0.29/ft2, we determined it would cost $216 dollars more to use MENTO 1000—and my client wasn’t sure about the additional cost. But ultimately he was convinced by the advantages: vapor-open breathability, but watertight moisture protection, more resilience to sun and wind exposure throughout the construction process, and long-lasting bonding to Pro Clima tapes to ensure an airtight building at every challenging joint. MENTO is like GORE-TEX for your house (except not microporous). Ultimately, he was convinced and we placed the order last week.

Then we came to the INTELLO interior air barrier. Why would he spend the extra money on this? Because, as it turns out, it pays for itself in less than a year. Here’s how.

We ran energy calculations per Washington State Energy Code 2015 using WSU’s energy calculator to determine how much energy would be needed to heat the house. We factored in the fact that a standard R-21 wall, constructed with Kraft-faced batts, drywall and primary vapor barrier, performs at only about 30% efficiency. That means the R-21 wall is effectively only insulated to R-6. Having shivered through winter in a tiny building that should have only needed a light bulb to heat it—at least according to the energy code—experience confirms this 30% performance value.

We then ran the numbers again assuming that INTELLO would be installed as an airtight, vapor-intelligent interior air barrier. In this scenario we rated the walls at 80% efficiency, turning our R-21 walls into an effective R-17.

When the numbers were extrapolated over a 6 month heating period assuming $0.09/kWh, the difference was profound. Our heat loads dropped from 19,000 kWh to 8,000 kWh. Translated into dollars: $1,734 dropped way down to $724. By using the INTELLO, we would be saving $1,000 dollars in heating costs per year—more than enough for it to pay for itself in just one heating season.

I am utterly convinced by both calculations and experience that installing INTELLO on the interior walls of any building is a simple short-term investment which more than doubles energy performance.

The 475 team recently had the opportunity to travel to Germany and spend a few days at Pro Clima headquarters in Schwetzingen and meet not only the entire Pro Clima crew, but also with fellow distributors from New Zealand and Ireland. Of course we focused on building science, testing, development, and new innovations for the upcoming year, but we also talked about philosophy. It was reassuring to discover that, the world over, Pro Clima teams agree: make great products, and let those products speak for themselves. Rather than spend time, energy, and money on hard sales tactics, hone in on creating the best possible quality and performance.

A Fair and Honest Warranty

Following this philosophy, Pro Clima introduced a new warranty. The 6 year warranty for individual Pro Clima products remains in effect, but is now extended to 10 years when those products are used as a system. In other words, when the airtightness & water resistant barriers systems are comprised of Pro Clima products – if applicable products are available. Pro Clima aims to be comprehensive, transparent, and fair in everything they do, with the promise to assume responsibility and clearly set themselves apart from the other building material manufacturers – with service, trust and backing this up with warranties.

You may think to yourself: “10 years isn’t that long. I’ve heard of manufacturers guaranteeing products for 40 or 50 years!” That may in fact be the warranty headline, but we question the accuracy of that guarantee. We challenge you to read the fine print on decades-long warranties. You may find, just as we have, that those guarantees wither away under the weight of a myriad of stipulations and legalese. Or simple provide you with replacement material – nothing more, nothing less. In contrast – ProClima offers a full replacement warranty including labor for the replacement work.

What You Get When You Use INTELLO Plus + TESCON VANA

• Optimal protection against mold – Pro Clima’s humidity-variable INTELLO is the first range of products to really offer full protection to building components. It seals to protect against humidity and is extremely open to diffusion to allow for optimal drying to the inside. The vapor curve matters, and with Intello, the permeance changes by a factor of 100 – the highest performance of any vapor retarder and it opens at the right time.
• Official certification of long-term performance – INTELLO has been tested and certified by the German Institute for Civil Engineering (DIBt) and is thus monitored by a third-party body. Intello is the only humidity-variable airtight membrane that has been approved by DIBt.
• Adhesion for 100 years – With the Tescon Vana solid acrylic adhesive tape you ensure the long-term durability of your buildings. Third-party verified by University of Kassel, Vana passed advanced age testing to demonstrate and adhesive bond capable of lasting 100 years – one century. That’s why we say ‘permanently airtight’.
• Top scores for indoor air quality – Ecology and healthy living environments have been important issues for Pro Clima from the time the company was founded. From European indoor air quality standards, to the stringent Sentinel Haus Institut standards, Pro Clima products perform top of class.

What this means for you

With Pro Clima and 475, you can benefit from our experience, reliability and expert, dependable support. The world of architecture and construction is at times chaotic and messy – we know this from experience. What we can offer that other systems can’t: if something goes wrong, we make it right.

Full warranty text can be found here.

While some might have serious issues with 2016, this year is shaping up to be pretty great for your friends here at 475. We have several things in the works that we’ll be announcing in the following months. But as with any business, everything starts with the people who make it. On that note, we’re happy to announce one big move and a couple new additions:

Ben Leer – Daylighting Specialist

Ben came on board early in 2016, and has proven his abilities as New York Product Consultant.
He originally found us through The City College of New York while completing his Master’s in Sustainability with a focus in architecture, naturally. He has a passion for creating environmentally friendly building, and is deeply committed to the Passive House movement. He’s now transitioning on to be our dedicated Daylighting Specialist. Ben is using his expertise to integrate and customize your daylighting details. Get in touch with Ben for consulting on a wide variety of daylighting components including LAMILUX skylights, windows, doors, sliding doors, motorized roof exit hatches and roof glazing systems. The sky is the limit… no pun intended.

For a sneak peek at what is to come in the daylighting department see 475daylight.com, ask him about the first 3 LAMILUX glass roofs being installed in the New York metro area, or read our most recent blog posts on BEWISO Windows.

Nick Shaw – New York Product Consultant

With Ben moving to his new position and shoes to fill, we were lucky to snag Nick Shaw from deep Appalachia. Nick is a PHIUS-certified Consultant and Builder. He graduated from Warren Wilson College in North Carolina with a BA in Environmental Studies with a concentration in Environmental Education. He’s familiar with a variety of high performance techniques from both hands-on building experience as well as theory. Nick has worked in the green building field for 8 years, primarily on integrated design-build projects. As per usual around our office, he’s a building science aficionado and self-described “sustainable design nerd.” To quote the man himself: “I believe what we create is a reflection of our worldview. I’m very happy to be a part of the 475 team and am excited by the amount of high performance buildings going up in New York.”

Aaron McCormack – Technical Consultant

475 High Performance Building Supply is a rare bird in the building world. There are few, if any, companies that we look to as a guide. Ecological Building Systems in Ireland is on our very short list of inspirations – they have been mastering the art of Pro Clima and Gutex distribution / education in Ireland and the UK for years.

With great pleasure, we welcome Aaron McCormack to the 475 team. He has served with Ecological Building Systems as a Technical Sales Engineer for the last 4 years. He holds a Bachelor of Science Degree in Architectural Design and Technology from Cardiff Metropolitan University. Aaron is looking forward to bringing his knowledge on airtightness, insulation and moisture movement to the company. He brings with him a passion for sustainability and Passive Design having recently become a Certified Passive House Consultant through the Passive House Institute.

We’re looking forward to learning a thing or two about airtightness from Aaron, and hope you have a chance to connect with him on pressing technical questions.

Five members of the 475 crew had the opportunity to travel to Europe over the last several weeks. The main target was to attend the 21st Annual  International Passive House Conference in Vienna. While we were in the neighborhood, we couldn’t resist meeting up with a few of our favorite manufacturing partners: PRO CLIMA, GUTEX, and BEWISO!

Enjoy the slides:

We’d like to thank all our manufacturing partners for the wonderful, educational, and enjoyable time. It’s an honor to work with such genuine, intelligent, and skilled people. See you all next year in Munich!

Passive House Windows, Not Only For Passive House

The core of Passive House is about energy performance, but the reasons we love aiming for the standard are all the other accompanying benefits. We want the comfort, the indoor air quality, and the silence. And we want the design to work for us. We saw a great example of this at a recent historic restoration project in Brooklyn that used BEWISO windows. BEWISO makes high quality, airtight, triple-glazed windows that transform the traditional thought and canon of energy-focused components.  Located on a city block slated for landmark protection, the clients Jo Irwin and Sydelle Kramer were looking to upgrade their windows while keeping the historic feel of the building.

One major concern with the project was sound attenuation. The building is located right next to an elementary school. The sounds of incoming school busses and shrieking children had driven the clients to the point of hysteria. As we’ve said before, quiet interiors are one of the main reasons Why New Yorkers Love Passive House (see & hear yourself in this video). Jo & Sydelle’s search for the highest quality sound reduction lead them to the 475 team. We were able to utilize our high performance building knowledge to provide an optimal solution. Our ANNE model all wood window from BEWISO is capable of providing sound attenuation at 47 dB. This was a pleasant surprise for the clients who had originally been looking at windows that maxed out at 42 dB. In addition to this they were thrilled at the unmatched reduction in the profile width of the frame. This gave them the ability and flexibility to match precisely the historic look of their home (the Victoria line has recently been Landmark Approved (LPC) in NYC – a first for a Passive House Certified window).

About The Windows

These windows and doors needed special glazing, triple-pane varied-width glass and spacers. BEWISO was founded by a woodworker, who at age 19 became the youngest person in Austria to achieve Master Carpenter status. This is why they’ve chosen from the start to specialize in all-wood windows that meet the highest standards (ie Passive House). For this project oak was determined as the best solution. The properties of oak have multiple benefits: the material itself is dense and is great at reducing sound transmittance; the stability and durability of the material guarantees longevity within the window itself; not to mention the sheer beauty of the wood itself, perfect for keeping the integrity of the fine woodworking details within the home. The design of the ANNE window uses a sleek elegant design which frees the confines of bulky frames and protruding transoms. The craftsmanship of the window allows for accurate and beautiful restoration at any scale.

It’s All About Blending In

The windows were built as a simulated double-hung window. It’s a simple and brilliant strategy – the top is a fixed sash with an offset operable bottom sash. The operation of the bottom portion of the window functions as a tilt and turn window. This feature is crucial to retaining the high level of airtightness that the BEWISO windows provide. Our window specialist, Ben Leer demonstrates here on the VICTORIA model of BEWISO simulated double-hung.

You may know that here at 475 we are kind of obsessed with airtightness. We say ‘the blower door is king’ and ‘airtightness is the driving force of performance.’ Here is yet another example of how airtightness affects performance. Sound moves by vibrating through the air. If you’re airtight, you greatly reduce the ability for sound to travel.  Vibrations don’t care if the gaps are in a walls, a window, or a door. The only way to block this sound is by using certified airtight components and installing them with the proper high performance window installs.

Since the performance of the windows are only as good as the install, we teamed up with J’s Custom contracting who have had experience in building several Passive House’s. With J’s high level of experience and 475’s expertise were were able to provide the highest quality window with the highest quality install. The result was fantastic,

And now from the lucky owners, let’s hear from Sydelle & Jo…

Sydelle Our bedroom is located on the exterior wall facing the street. We used to hear all sorts of conversations from people passing by. It was almost as if we were walking along side them. With the new windows from BEWISO we can’t even hear the garbage trucks that used to wake us up every morning.

Jo We had lived in our home for over 40 years, during which we had made very little changes to the look of our interior. I was really nervous about the window upgrade because I had heard that energy and sound efficient windows had really bulky frames. This would have ruined the entire look of our home. Luckily 475 and BEWISO had a solution that could provide both the performance and the beauty. The final install seamlessly match the existing interior, the only thing I notice about them is how little sound they let in.

Get in touch for more on this project, BEWISO windows, or daylighting in general.

Ensuring a continuous air barrier is top priority for high-performance building. Joint connections between different materials can be especially challenging points to airseal. Acrylic caulk adhesives can solve some of these problems, but is not always the fastest way to a robust connection.

For example if you’re attaching two airtight, vapor-closed surfaces, such as the case with sub-slab vapor barriers, a product that needs to cure out water (CONTEGA HF/classic or other acoustical sealants) may take days to dry and/or will never set properly. CONTEGA MULTIBOND is the ideal for situations that call for speedy application. It’s a flexible, instantly bonding, airtight and waterproof joint adhesive suitable for both interior and exterior use. It comes on a pre-cured roll, much like a long, narrow, but slightly fat roll of tape, and is sold in packs of two 32’9″ (10m) length rolls – for a total of 65’6″ linear feet in each package.

Where to use CONTEGA MULTIBOND

CONTEGA MULTIBOND, easily applied from a roll, forms an instant airtight connection between interior and exterior membranes and adjacent structural elements.

CONTEGA MULTIBOND is a solvent-free, form fitting, frost-resistant airtight adhesive applied from a roll. It’s designed for attaching airtight interior membranes and WRBs, such as INTELLO PLUS and SOLITEX MENTO, to adjacent structural elements (metal/concrete)), sub-slab vapor barriers, or sheathing. CONTEGA MULTIBOND will adhere to mineral surfaces such as concrete or plaster, and wood surfaces that are rough or painted. Smooth surfaces like hard plastics, un-rusted/clean/painted metal, and hardwood panels like plywood and OSB are all readily bonded to. The airtight connection forms instantly – no drying time needed (ie ready to blowerdoor) – and achieves its final level of strength after 24 hours.

Low Temperature Application

CONTEGA MULTIBOND can be applied in temperatures as low as 5°F (-15°C), and once applied will perform from -40°F to 212°F (-40°C to 100°C). Solar exposed roofs can reach temperatures in hot climates as over 180°F, so the wide temperature range of MULTIBOND makes it suitable for use in a variety of climates.

Preparing the Substrate

SOLITEX MENTO, an exterior WRB, is applied to a rough surface using CONTEGA MULTIBOND.

As with any air barrier application, it is important that your surface is clean before tapes or adhesives are applied.

Dust & Dirt

Dust and dirt should be swept off of the taping surface, because otherwise the SOLID-acrylic adhesive will tape to them and dust and dirt are not airtight.

Grease & Silicone

Grease and silicone, because they reduce the surface tension of the substrate, compromise the effectiveness of the bond.

Pro Clima backing strips and release paper are also made of silicone – so if your surface has silicone on it, the adhesive will release as designed. Wiping and cleaning grease off of your substrates (some OSB or metal studs) and/or TESCON PRIMER RP to prep them  will significantly enhance the strength and durability of the connection.

Rough & Porous

For surfaces that are rough, uneven, or porous, such as masonry or brick, it may be necessary to prime the substrate before attaching CONTEGA MULTIBOND.  Although MULTIBOND is designed to attach to rough substrates, and can be pressed into cracks and rough areas, priming the surface with TESCON PRIMER RP is extra insurance against unstable sustrates – and assuring airtightness of your assembly. Priming will also be necessary in cases in which the subsurfaces have insufficient load-bearing capacity. For particularly challenging surfaces, two layers of CONTEGA MULTIBOND can be applied on top of each other to ensure a fully sealed, even and durable bond.

For particularly rough surfaces, two layers of CONTEGA MULTIBOND can be applied to one another to ensure permanent airtightness.

Healthy

CONTEGA MULTIBOND contains no plasticizers, solvents, emulgators or preservatives. It scored top-of-class in the hazardous substances tests, receiving an A+ French VOC emissions rating, and performed very well according the German Committee for Health-Related Evaluation of Building Products (AgBB) evaluation scheme.

Find Out More

CONTEGA MULTIBOND is an indispensable, easy-to-use solution for ensuring airtightness at challenging joint connections. Check out the CONTEGA MULTIBOND product page for more information, and contact us if you would like a small sample to try out for yourself.

When advocating for Passive House buildings it’s often not very convincing to point to successful projects in other countries.   People understandably want to see local professionals working successfully with local builders and local owners. Local examples of Passive House building are critical to achieving popular acceptance.

Consequently, 475 is happy to support the recent publication of Passive House Buildings: New England Forges Ahead which showcases 50 projects located across New England.   Published by Low Carbon Productions and organized by the regional Passive House associations Passive House Massachusetts (PHMA), Passivhaus MAINE (PHME), Vermont Passive House (VTPH) and Connecticut Passive House (CTPH).  In the books forward they note:

We showcase the pioneering work of New England Passive House enthusiasts in their first decade of innovation.  They blazed a trail beginning with a few homes that led to the more recent Passive House apartments, schools, and mixed-use buildings.  These buildings are beacons lighting our way forward.

The beacons also reflect the warm glow of a tight but fast growing community of professionals that appreciate the need to share knowledge and welcome and encourage newcomers.   In fact for us it feels like a family photo album – so many familiar names, faces and projects…so many great stories.

Of course we’ve supplied lots of materials and components to countless projects – airtightness and moisture protection by Pro Clima, ventilation system by Lunos, skylights by Fakro and Lamilux and wood fiberboard insulation by GUTEX – but what we enjoy and appreciate are the details, the communication, the site visits and trainings, that allow us to participate in this vibrant community.

Jesper Kruse of Passive House Maine, expresses a sentiment shared by many Passive House advocates:

Once I heard 80-90 percent reduction in heating energy consumption, what is there to talk about after that?  It is so obvious Passive House is where we need to be headed.  I have children.  I know about climate change.

With designed and built schools, multifamily developments and single family homes, this book shows Passive House in service to the local character.  Leonard Wyeth, a founder of CTPH writes:

As New Englanders, we have a reputation of being Yankees.  Politely described as frugal, we don’t like spending money on oil, gas, and electricity. When you come right down to it, we’re thrifty and we’re practical.   In Connecticut’s climate, comfort usually comes at a high cost.  Warm in winter and cool in summer usually requires a lot of energy. That’s our problem: we can’t be both comfortable and thrifty….Or can we?

Yes, we can. And clearly New England Yankees can do it, and are doing it in a convincing manner.   Congrats!

What Are We Doing?

Are we kidding ourselves? Trying to be a conscientious consumer, we try to pick sustainable materials and products – making more sustainable decisions – with the desire to “vote with our wallets” and promote “green industry” that will have beneficial effects in our fight against climate change and other environmental and social degradation.

At the immediate level – there are tremendous benefits to making healthy, low-energy, robust buildings – for the construction workers, occupants and owners.  But do such individual actions really make the larger change we want?  Or, beyond those immediate benefits, do they just make us feel better about ourselves?  Can we make the difference, and systemic change, our environment desperately needs?

The Problem

Recently reading Conscious consumerism is a lie. Here’s a better way to help save the world by Alden Wicker, one is struck by the idea that our myriad of personal choices: organic, local grown, fair trade, recycled – just doesn’t add up….at all.   The very structure of our consumer centric economic system seems to guarantee it.

She writes:  “Case in point: A 2012 study compared footprints of “green” consumers who try to make eco-friendly choices to the footprints of regular consumers. And they found no meaningful difference between the two.”

Turns out that sustainable choices don’t add up to sustainability. Ouch.  And it’s worse still.

Ms Wicker says: “On its face, conscious consumerism is a morally righteous, bold movement. But it’s actually taking away our power as citizens. [our emphasis] It drains our bank accounts and our political will, diverts our attention away from the true powerbrokers, and focuses our energy instead on petty corporate scandals and fights over the moral superiority of vegans.”

It rings true.  Too many see their moral personal choices as absolving themselves of the need to actively engage the root of the problem: the political and economic levers that set the context and load the dice.

And so while we appreciate that a consumer chooses more sustainable materials and chooses to build a high performance, low energy and Passive House  because they understand it can serve as the foundation of society’s carbon negative future, driving down power demand and supporting a 100% renewable power supply, simply building them; 10, or 10,000 is not enough.  Only building Passive Houses will never be enough.

The Solution:  Action in Two-Parts

So what’s to be done?  Can’t we do both?  We want to buy as little crap as possible – crap that is polluting our oceans and driving climate change.  And we need to change the system too.  To avoid the trap it’s a two part action.

But let’s turn it around.

First

Get political.  Get your local officials to care about climate change and their community’s carbon budget.  We need to go carbon negative – how are they going to do it? Sign the petition, attend the rally, volunteer for local activist organizations, contribute money for political action, get involved. Once leaders finally ask “how?”, the landscape shifts.

Looking at their carbon budget, leaders will note that buildings are a disproportionate part of the problem –  accounting for 40% of carbon emissions generally, and 75% of overall emissions in major cities like New York.   Therefore, buildings will be a big part of the answer too.   And only Passive House buildings deliver the reductions commensurate with the carbon accounting deficit policymakers are facing.

In places like New York City and Vancouver we see this dynamic starting.  Local Passive House activists like New York Passive House and Passive House Canada, working with allied organizations and individual advocates, are helping political leaders and bureaucrats find policy levers to advance Passive House building capacity, knowledge and yes, actual buildings.  (See the action this June 16th, in NYC, at the NYPH17 conference.)

Second

Build.  As consumers we should choose Passive House, and build them.  That choice can be leveraged to achieve much more than simple conscientious consumerism. If local policy makers can point to local examples – the political landscape can improve dramatically.  Build it and share it.

Connect the Dots

For us to adequately address the climate crises – it can’t be this or that.   Let’s not be discouraged by the inadequacy of any individual act.  We can’t be constrained by a zero-sum game “dead end” – but instead let’s see how all our actions can be leveraged to leapfrog limitations and unleash exponential improvement.   Yes, eat real food, consume less plastic & fossil fuels, build energy efficient buildings, AND engage the political process.

Make it “Yes, and…”    Passive House + Renewables.   Let’s change the system.

Related Blog Posts:

What’s 475 About – Reflections for a New Year

Make Better Choices: Toward A Less Toxic World

Why Passive House?

A Smart Enclosure Starts with Smart Walls: Green High-Performance Done Right For Our Sustainable Future

After HVAC systems, water heaters can be among the biggest energy sinks in a building. Although high-performance building strategies can allow you to dramatically downsize your HVAC systems, supplying hot water can remain a challenge for those seeking to reduce building energy loads. Fortunately, the ideal solution to the challenge has arrived: the SANDEN SANCO₂ Heat Pump Water Heater. With a stainless steel storage tank, lowered energy demand, elimination of traditional refrigerants and the best performance around, the SANDEN SANCO₂ may well be the water heater to end all water heaters.

Unlike conventional heat pumps, the SANDEN SANCO₂ uses carbon dioxide as a refrigerant. Because of the properties of CO₂, this allows the SANCO₂ to function efficiently across a wide temperature range: it is able to extract heat from the air down to ambient temperatures of -20°F, and works without a backup coil or heating element in a wide range of climates. There is no capacity loss or reduction in COP above freezing; below freezing, there is only a small reduction in COP, far lower than traditional circulating coolants. The SANCO₂ warms water up to 175°F at a rate of 0.3 gallons/minute. And with a first hour rating of 97.8, the highest in the business, the SANCO₂ is almost twice as efficient as traditional heat pump water heaters.

For both energy efficiency and reducing the environmental impact of buildings, the SANCO₂ is ideal. Because of the high efficiency of the CO₂-based heat pump system, the SANCO₂ uses 70% less energy than traditional water heaters. The system runs on electricity, and therefore has the potential to be emissions-free. Operating costs and emissions can be further mitigated by running the system on off-peak power, and storing hot water for later use. And when compared other refrigerants commonly used in heat pump systems, CO₂ has relatively low global warming potential, and is not ozone-depleting. Other refrigerants often found in these heat pump systems, such as R410A, have global warming potential as much as 2000-4000 times higher than CO₂.

Efficiency and Performance

• Coefficient of performance (COP) of 5.0, by far the highest of any system on the market
• Heat pump capacity of 4.5kW, or 15,400Btu/hr
• Uses 70% less energy than traditional water heating systems
• Ambient air operating temperature range: -20°F to 110°F
• Water temperature setting range: 130°F to 175°F
• Highest first hour rating (97.8) of any heat pump water heater – almost twice the average for traditional HPWH systems
  • 101 gallons at 135°F delivered in the first hour for the 83-gal system
• Warms water at a rate of 0.3 gallons/minute
• Energy Factor (EF) of 3.84 for the 83-gal system (NEEA Tier 3+)
• Backup electric heating element not needed in the storage tank
• Water can be heated using off-peak power, further reducing operating costs
• Faster recovery after a hot water draw than traditional HPWH systems

Design and Installation

• Two part system (exterior compressor and interior water tank) allows for easy installation and maintenance
• Tank and compressor can be installed as much as 50 feet apart, with 16 feet of lift
• Outdoor noise operating level of only 37dB is whisper-quiet
• The slimline design of exterior compressor significant reduces its footprint relative to traditional compressors
• Scalability: additional compressors and/or tanks can be added for larger buildings
• All controls located in tank/indoor thermostat

Quality and Longevity

• The stainless steel storage tank is corrosion resistant, and carries a 15-year warranty
• Compressor, refrigeration system, and all other outdoor components carry a 10-year warranty

The “split” design of the SANCO₂ HPWH is another unique design feature that enhances the performance of the system. Traditional, integrated HPWHs, in which the compressor and the tank are co-located, draw heat from the interior of the building and therefore cool year-round – not ideal in colder climates, as it would increase space heating demand. The SANCO₂ uses outside air instead, and the outdoor compressor can be as far as 50 feet from the interior tank, with as much as 16 feet of lift. The hot and cold water pipes connecting the compressor to the tank are only 1/2″ in diameter, allowing for integration of the units even at a distance (use Roflex 20 or Roflex 20 Multi to air seal line sets). And because both units are far smaller than traditional HPWH systems, the tank can easily fit anywhere, and the slim profile and relative quiet of the exterior compressor make it easy to place near the home.

SANCO₂‘s applications are not limited to simply providing domestic hot water – though it does a fantastic job of meeting all DHW needs with much less energy than conventional systems. But because of its efficiency, for buildings with very low heating demands – like passive or near-passive houses – the SANCO₂ can provide hot water for both DHW needs and for space conditioning. Because of its ability to meet these simultaneous needs and be integrated into a dual heat pump water heater-space conditioning system, SANCO₂ serves as an ideal solution for high-performance, multi-family buildings and low-energy homes. Download the brochure for a handy summary of the system.

Nice array of Sanden systems getting ready to come on line for a multi family in downtown San Francisco pic.twitter.com/2zc7BR9lmc

— Sanden Water Heater (@sandenCO2HPWH) June 1, 2017

Flanged windows are ubiquitous in American construction.  As we push toward higher levels of enclosure performance – with increased insulation levels, airtightness and vapor control – window specifications are getting more robust too. And while it can be a relatively straightforward thing to select a better window, it isn’t so readily clear how to match it with a better installation.

Let’s make a high performance installation too. Download the guide here (PDF).

Simple is Better

It needn’t be complicated.

There are a few key concepts that guide us:

• Absolute control layer continuity: of water, air, insulation, and vapor control – from component to component.
• Maximize drying potential, to build drying reserves and a safety buffer.  In cold and mixed climates this means vapor open toward exterior and vapor variable toward interior.
• Durable and cost effective: with quality components, properly installed, the installation should exceed the life of the windows, no call backs and no up-charges.

Armed with these three commandments, we breakdown, tweak, and repackage the familiar steps of installing a flange window.

Outboard

The WRB is a high-performance three layer monolithic membrane – SOLITEX Mento 1000: waterproof, airtight and vapor open.  We make connections in a weather-lapped fashion, always starting at the bottom and overlapping materials as we work up, assuring proper drainage.   EXTOSEAL Encors, a self-healing, highly form fitting butyl-acrylic adhesive forms the sill pan.  Face tape with CONTEGA Solido EXO, a vapor open, airtight and waterproof SOLID acrylic adhesive with highly form-fitting fleece backing.  One may also face tape with TESCON Vana, waterproof, airtight and vapor permeable all-around SOLID acrylic tape.

DO NOT FACE TAPE WITH VAPOR IMPERMEABLE TAPE: IT DAMS MOISTURE IN THE WALL

Because the WRB is our outboard airtight layer the connection to the flange and window must be continuous all the way around – this includes at the sill and heads.  We are making a waterproof enclosure so moisture intrusion should be minimal, but in case there is some moisture intrusion, the vapor permeable nature of the flat taping assures drying capability and protection from damages.

Inboard

If the framing cavity is insulated, there should be an airtight and vapor variable control layer inboard of the insulation.  INTELLO Plus is the most robust smart vapor retarder available and is extremely airtight.   Connecting the membrane to the window becomes essential – for moisture protection, comfort and efficiency.   We make these connections with TESCON Profect or Profil tapes.  With split release paper backing, these tapes are made for making tight inside corner connections.  We show how to premake corners so that these tightest of spots are successfully dealt with.

Download the Guide

We hope you find this step-by-step instruction guide useful. DOWNLOAD HERE (PDF).  Complete your high-performance enclosure with with a high performance flange window install.

Related Blog Posts:

• Smart Wall Primer
• How To Prepare For High Performance Windows
• Pre-make Window Corners With TESCON Profil
• Applying Extoseal Encors
• Heavy-Duty Window FLashing by Chris Corson Using Extoseal Encors

Monitoring real life assemblies is the best proof of performance. This is how we know Pro Clima products make construction as safe as possible.

ECOCOR monitored a foam-free, un-vented flat roof in Maine and clearly demonstrated how elevated assembly humidity in a super-insulated assembly can safely dry inwards through INTELLO Plus.

As we describe in the presentation High Performance Gets Real, a vented roof is generally preferred because of the added drying potential it can provide. However, space constraints can make an un-vented roof necessary. In this case, the builder also preferred the robustness of dense pack cellulose with the INTELLO Plus airtight smart vapor retarder membrane.

Moisture sensors were placed at the inside of the exterior ZIP/OSB sheathing and at the I-joist cord just above the inboard INTELLO. The sensors recorded Wood Moisture Equivalent percentage (%WME), or Moisture percentage (M%).

As with most residential projects, the assembly contained primarily wood-based construction materials. The cellulose and wood moisture contents started at elevated levels because of how they were delivered and installed.

But no harm was done. The collected data, provided by ECOCOR, shows that the roof assembly dried out within the first summer. At the exterior sheathing ZIP/OSB sheathing (orange data line), moisture levels never exceeded our recommended safety buffer limit of 15M%.

The interior data points (blue line) also shows moisture levels trending downward each year – indicating how effectively INTELLO Plus builds drying reserves through inward drying.

See more of our moisture recommendations in Drive Safe, Build Safe.

Chris Corson, and Kohta Ueno of Building Science Corporation, presented (in part) on this assembly at the NESEA conference in Boston, which you can find here on the NESEA site.

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Related Blog Posts:

• JLC Reports on Success of Foam-Free Unvented Flat Roof Assembly
• The Ten Golden Rules for Foam-Free Flat Roofs
• The 8 Golden Rules for Foam-Free Unvented Asphalt Shingled Roofs
• 475 Presents: High Performance Gets Real
• Drive Safe, Build Safe
• Yes, Unvented Roof Assemblies Can Be Insulated With Fiberglass; A WUFI Post
• New Mold Growth Index and Safe Double-Stud Walls: WUFI Pro Shows INTELLO Plus is Key
• INTELLO & DB+ Approved by DIBt for Use in Unvented Hot Roof Assemblies