2012 was the first year the International Energy Conservation Code required residential construction to pass an air leakage rate test, better known as a blower door test. My area of the country requires the test to be at or below 3 air changes per hour at the test pressure of 50 pascals (ACH50). (Other areas, typically warmer climates require 5 ACH50.) Most new construction in my market has no problem passing the test, but I have had a handful of houses fail, usually the failed tests are by a builder having their first blower door test or the project is a very small home.
Whether you are performing blower door testing or hiring someone to perform the test for you, it’s a good idea to understand how a home should be setup for the test. Should a door be open or closed? What can be sealed off? How to address rooms attached to the house but are outside the air control layer? That’s today’s topic, attached garages and three season porches. How should those spaces be setup for a blower door test?
Air leaking into a home (infiltration) or out of a home (exfiltration) happens naturally in every home, new or old. No matter how much air sealing is performed, we just can’t make them completely air tight. I’ve tested some new homes that were very tight, .33 ACH50, (anything under 1 ACH50 is very good) and I’ve also tested many older ones that aren’t so tight, we can use my 1952 Cape as an example, 9.71 ACH50. In this post, I’m going to discuss how to manually calculate the cost of the air leakage and examine what we can do with that number. Continue reading “Energy Audit-Calculating the Cost of a Home’s Air Leaks”
An energy audit is an inspection and analysis of how a building uses energy. To get an accurate analysis, tools are needed to perform testing. You would think that a blower door and thermal imaging camera would be my most commonly used tools during an audit, I do use them often, but there are a couple I used more. This posting is all about my energy auditing toolbox. Continue reading “Energy Audit-Tools of the Trade”
I think most of us know of this man, one of the founders of The Energy Conservatory and designers of the Minneapolis Blower Door. I recently had the opportunity to chat with Gary. My intent with the interview is a little different from other interviews that have featured Mr. Nelson. I wanted to ask questions from a practitioner working in the field point of view. Continue reading “Building Science-An Interview with Gary Nelson”
Whether you are using equipment from Minneapolis Blower Door, Retrotec, or any other blower door manufacturer, one of the first steps in conducting a blower door test is to measure the home’s floor area, volume, and surface area. Coming up with the floor area is the simplest, length times width. Calculating volume also isn’t hard, width times length time height, simple right? Not always, getting the volume of a geodome or a complex cathedral ceiling often takes some time. Continue reading “Energy Audit-Measuring for Blower Door Testing”
A blower door is an expensive tool. A full kit including frame, panel, fan and manometer will cost more than $3500. Add in the other tools for finding air leaks and you could easily drop over $5000. And then you still need to have some training to understand how to operate and interpret the results. Continue reading “Energy Audit-Homemade Blower Door”
This week, I’m going to start a new category of subject matter to discuss, the tools I own and use when conducting energy audits, assessments and performing home diagnostic testing. We are going to start with my number one diagnostic tool, the blower door. Continue reading “Diagnostic Tools-Blower Doors”