This post originally appeared on the Green Building Advisor website.
Code compliant blower door testing of a small home can be very frustrating for both the person performing the test and the homeowner or contractor who are required to have the test. A few months ago, I tested a 952 square foot, newly constructed home with a volume of 7616 cubic feet, one of the smallest I’ve tested. The house had a leakage rate of 416 cfm which resulted in a 3.28 ACH50 number. A failed blower door test (my climate requires 3 ACH50 or less). If we take that same CFM rate but increase the ceiling height to 9 feet, which changes the volume to 8568 cubic feet, 2.91 ACH50, a passing test. Either way, 416 CFM of air moving through the blower door isn’t much, some kitchen exhaust hoods can move more air than that. Seems unfair to punish smaller homes when blower door testing, especially when the blower door test is testing the surface of a structure, not it’s volume.
Continue reading “Code-Blower Door Testing a Small Home”
The way we build a home is constantly changing. New codes come out every three years, new technology is evolving faster than I can keep up, and new materials help to make building a home easier. (Sometimes!) So, what are we striving for? Continue reading “Codes-Crystal Ball”
I recently wrote a blog post titled Building Science-Building Shell Layers-Vapor Control Layer. This blog is going to expand on that discussion with information on several choices of vapor retarders. Continue reading “Construction Materials-Vapor Retarders”
I’ve talked about blower door testing several times on this blog. This discussion will dive deeper into this type of test, when it should be completed, the different tests done with the blower door, and interpreting the information. Continue reading “The Energy Audit-Blower Door Test”
In our northern climate, how quickly a structure loses heat is dependent on three factors, the first is transmission heat loss which includes the difference between inside and outside temperatures, called the delta T, and the resistance to heat flow, or R-value of the building assemblies. Continue reading “Building Science-R-value”
In this blog, I’m going to discuss building tightness and the code dealing with air leakage. The 2012 International Residential Code for One and Two-Family Dwellings is the current code in force for the state of Minnesota at the time of this blog. Chapter 11 deals with energy conservation, what most in the building industry call the energy code. The code on building air leakage states: Continue reading “Building Science-“Breathe””