How to Integrate a Window into a Water Resistive Barrier

The building science community talks a lot about control layers.  I’ve written on the topic several times, basic overview of these principles which can be found at: A Crash Course on the Four Control Layers.  Let’s take a deeper look at water resistive barriers (WRB) and how windows and doors need to be integrated into the WRB.

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How a Window Manufacturer Tests Thier Products

As builders and homeowners, we are interested in how a window or door performs, their longevity and durability, and how easily they install, and of course the cost.  Have you ever given thought to how a window or door is tested by the manufacturer?

I recently had the opportunity to tour Andersen Windows and Doors research and development department, a place called the Garofalo Center for Research, Development and Innovation.  This is the facility where, in the words of Andersen, they “test to failure”.  Stated in another way, they don’t test to see if a product simply passes a required testing standard, Andersen wants to know at what point their products fail. Continue reading “How a Window Manufacturer Tests Thier Products”

Building Above the Energy Code

What is an energy code?  Energy codes are part of the building code that regulates how heat and energy are used in a building.  By now, most builders understand there are minimum insulation levels, in walls, floors and ceilings.  There are also requirements in how windows and doors perform.  Air tightness testing and mechanical system performance (both in space heating and water heating) are also part of the energy codes.  Local jurisdictions adopt (sometimes modify) and enforce these codes.  Updated energy codes are released every three years.  The 2024 IECC has been released, but most jurisdictions are looking to adopt the 2021 version, which you can read here: 2021 INTERNATIONAL ENERGY CONSERVATION CODE (IECC) | ICC DIGITAL CODES (iccsafe.org)

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What You Need to Know About Thermal Imaging Cameras

I purchased my first thermal imaging camera back in 2009, it was an Extech i3 (made by Flir).  The $1200 camera had a resolution of 60×60, total pixels of 3,600 and shot photos only in thermal (no digital photo overlay).  If you don’t understand any of those terms, that’s okay, you will have a basic understanding of how thermal imaging works by the end of this article.  Oh, and by the way, you can now purchase more than twice the camera I had in 2009 with half the cost.

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What to Know About Construction Sequencing in High Performance Projects

This post first appeared on the Green Building Advisor website.

I was a builder for more than 10 years before I attempted my first above code building project.  There was an order in the way I built early in my career that usually kept my projects moving smoothly.  That schedule went out the window with my first attempt at constructing a higher performing home.

Integrating high levels of air tightness, greater R-values, along with other elements to improve performance can result in assemblies and installation details going out of order from traditional construction practices.  The easiest and most logical construction schedules often need adjustments.

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How to Prioritize Energy Upgrades to an Existing Home-Part 2

I purchased my home in the fall of 2018.  I could have decided to build something new or forgo all the maintenance that comes with home ownership and rent.  Instead, I chose to purchase an older home that needed updating, both in appearance and performance.

The 24’ x 32’ home was built in 1952, a Cape Cod design with the normal problems of a Cape Cod, attic knee walls that were both inside and outside the air control layer.  There was some evidence of past water damage and a few old clips on the roof where a heat tape would have been placed, suggesting an ice dam issue.  The high efficiency natural gas forced air furnace appeared to be from the 1990’s, the same year as the electric water heater.  There was also a natural gas fireplace in the small living room.  There was a weird-shaped room on the main level (behind the sun and where the sliding patio door is located, 9’ wide by 24 feet long.  Two bedrooms, and a bathroom were located upstairs, a bathroom on the main level, and an area in the basement that had an egress window well that would support another bedroom. Continue reading “How to Prioritize Energy Upgrades to an Existing Home-Part 2”

Blower Door Testing for Contractors, Should You Own One?

This post first appeared on the Green Building Advisor Website.

I had the opportunity to interview Gary Nelson, one of the founders of The Energy Conservatory and Minneapolis Blower Door a few years ago.  An Interview with Gary Nelson-NorthernBuilt.  During the interview, he made the comment that his hope for the blower door when it first started appearing in the market was that every contractor would own one and that testing both existing and new homes would become a common practice.  That was 40 years ago.

We haven’t got there yet, but there are more and more contractors purchasing the tool and there are many online videos and webinars showing how a blower door is set up and used.  In this blog, I’ll discuss how to perform basic diagnostics on a home using a blower door.  Methods used to find air leaks, a short discussion on zonal pressure testing, and different tasks that the manometer can perform, all topics I think a contractor that owns (or wants to own) a blower door should be familiar with.

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How to Prioritize Performance Upgrades to Existing Homes

I’ve been performing a semi-deep energy retrofit to my home for the past 5 years, and at my current rate of progress, it will be another 5 years before I’m complete.  This leads to a question; how does a person prioritize the work to be done?  Are the easiest items to complete done first, or the stuff that provides the biggest return on investment a better place to start?  This blog discusses my suggested priorities.

  1. Structural decay must be dealt with first.

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The Effects of Poorly Installed (or Missing) Insulation

I was taught many years ago by an older fiberglass insulation contractor the importance of a quality insulation job.  His biggest piece of advice, FLUFF, DON’T STUFF!  Poorly installed insulation can have a big impact on the overall performance of a home.  In this blog, I’m going to show you mathematically how a small insulation deficiency can have a big effect in how a home performs.

This thermal image is a good example.  This was a brand-new home where I was performing a code required blower door test.  I ran around the home with my thermal imaging camera before starting the test and thought I might be able to use this image to show thermal bridging, which it does a good job at, but if you study the pic a little closer, we see several areas where the fiberglass insulation was poorly installed.  Compressing (not fluffing) the product creates areas of cooler temperatures in the insulation batts.  The dark area (at the ceiling on the right side of the photo) shows an area of missing insulation.  What effect does this poorly installed insulation have on the overall (effective) R-value?  We can show the results mathematically.

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Choosing the Right Vapor Retarder for Crawlspace Encapsulation

This post first appeared on the Green Building Advisor Website.

When I first started working in the trades, back in the mid 1990’s, I was working for my brother as an apprentice electrician.  We had an agreement, he would perform any work needed in attics, I got crawlspaces.  Some of the work we were performing was on seasonal cabins that were being updated for use during Minnesota’s cold winter.  These cabins were constructed decades earlier, built very close to the earth.  Sometimes there were even stumps from the trees that were cut down to make room for the cabin that were left under the structure, in the crawlspace.  More than once, I was sure the fire department was going to have to be called to extract me from under one of these cabins.  Most were vented crawlspaces, some you couldn’t tell if they were vented or unvented, and very few had any type of vapor retarder or soil gas mitigation system present.

One of the many crawlspaces I’ve spent time in. This one featured a puddle of raw sewage and unsealed ductwork. This was a vented crawlspace in a very cold climate, no insulation in the floor system or on the crawlspace walls.

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