Design & Construction Resources
The Double-Stud Wall Simplified: Low Cost, High Performance
Low Cost High Performance Simplify. The double-stud wall is a well established method for creating a very economical, durable and high R-value assembly in new construction - and is one...
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How To Prepare For High Performance Windows
Windows might make you nervous. They’re big, heavy, fragile—and in a high-performance building, they’re the most expensive components. But that cost delivers real value: high-performance windows offer exceptional comfort and...
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An Interior Air Barrier Does It Better
Ever tempted to wear your underwear over your pants? Neither are we! But when it comes to buildings, we’re seeing a lot of common practices that are equally backwards. It...
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How To Make that Old Leaky Masonry Row House Airtight
The historic masonry row house (or "brownstone" as we call it here in New York) is a common contributor to the character in many cities and small towns. When...
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How to Keep Floor Beams Where They Should be - Inside the Airtight Layer
You know the air barrier must be continuous, without interruption around the entirety of the conditioned space - inboard of the main insulation layer, thereby keeping the conditioned air within...
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5 Steps For Sealing Intentional Holes in Your Air Barrier
A continuous air barrier is one of the defining design details of Passive House and high-performance building. The red line that many of us draw on blueprints to indicate the...
Read MoreFlanged Window Install Guide for High Performance Enclosures
Sequencing For Making Flanged Windows Airtight Flanged windows are ubiquitous in American construction. As we push toward higher levels of enclosure performance;- with increased insulation levels, airtightness and vapor control;-...
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Double-Stud Walls: WUFI Pro Shows INTELLO is Key
New Mold Growth Index and Safe Double-Stud Walls 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...
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Common Air Barrier Failures and How to Avoid Them
Top Ten *NO* Eleven Air Barrier Failures 1. It's not continuous! Mind the gap! The mother of all failures. You don't have an air barrier if it's not continuous- it...
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How to Stay Airtight When Buildings Move
Buildings move. Ensuring that your air barrier is resilient to movement is crucial to ensuring the longevity and performance of your building. Unless you're building a structure using just one...
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4 Hurdles to Hitting Passive House Performance & How to Overcome Them
4 Hurdles to Hitting Passive House Performance & How to Overcome Them Passive House performance is the future of building. As with any trip there are obstacles. Yet professionals new...
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Vapor Venting An Unvented Roof: Added safety by adding a Vapor diffusion port
"Classic Ridge Rot" documented by the Building Science Corporation in Alaska Planes can fly safely with one engine. And you can keep your pants up with just a belt. But...
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How To Stay Airtight Without A Service Cavity
Intro / Caveat As you may know, 475 recommends you use a service cavity on the interior of high performance, airtight building envelopes. We've enumerated the values of service cavities...
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Airsealing Beam Penetrations
Joist Connections Add Up Plaster is a great airtightness solution for party walls. But connections to the joists need to be addressed. This Ecostruct project achieved 0.23ACH50 after this plaster...
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The 8 Golden Rules for Foam-Free Unvented Asphalt Shingled Roofs
When insulating a wood roof structure, 475's goal, as always, is to build in the most healthy, structurally sound and ecologically friendly way – thereby achieving truly high performance....
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Historic Masonry: Notes and Details
475 in many ways started with historic masonry retrofits, and with our HQ surrounded by Brownstone Brooklyn, we are helping a great many of these 100+ year old buildings get...
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2 Simple Ways To Airseal Wires & Pipes
It's great watching the Proof is Possible Tour. We have an addition to the information given by Corbett Lunsford in their last progress video. See our response video below.
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Yes, Unvented Roof Assemblies Can Be Insulated With Fiberglass - A WUFI Post
And Not Just In Climate Zones 2B & 3B: Cold Climates Too A post on August 21st, 2015 on GreenBuildingAdvisor.com, Martin Holladay asked the question, Can Unvented Roof Assemlies Be...
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The Service Cavity: Making Airtight Construction Easy
We are making homes as airtight as possible. This is because airtightness greatly effects indoor air quality, thermal comfort, and energy efficiency - while protecting the enclosure from moisture damage...
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Insulating Historic Masonry Buildings Safely: How WUFI Can Help
With the rising popularity of Passive House and EnerPHit renovation in brownstone and brick masonry renovations in the US and Canada, the question comes up time and time again: What...
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