I have talked many times about blower door testing, air sealing and air leaks in this blog, on the Green Building Advisor’s website, and more recently, in the pages of Fine Homebuilding Magazine. Most of what I’ve written deals with testing a home or techniques used in air sealing a home. This time I’m going to discuss the mechanisms that cause air to leak, there are only three of them, but first a little science. Continue reading “Building Science-Three Way Buildings Leak Air”
Energy Audit-Calculating the Cost of a Home’s Air Leaks
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”
Building Science-An Interview with Gary Nelson
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”
Energy Audit-Measuring for Blower Door Testing
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”
Energy Audit-Homemade Blower Door
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”
Diagnostic Tools-Blower Doors
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”
Energy Audit-Blower Door Testing-A Deep Dive
I’ve talked about blower door testing several times on Green Building Advisor and on this blog. This discussion will dive deeper into blower door testing, when it should be completed, the different tests done with the blower door, and interpreting the information. Continue reading “Energy Audit-Blower Door Testing-A Deep Dive”
Opinion-5 Reasons to Own A Blower Door
By now most of us know what a blower door does and the basics of how they work. All energy auditors and raters own one. A few insulating contractors I know also have purchased their own blower door. As a contractor, does it make sense to invest a sizable amount of money and then take the time to learn how to operate this piece of test equipment. Continue reading “Opinion-5 Reasons to Own A Blower Door”
Energy Audit-Advanced Blower Door Testing-Zonal Pressures
Most of us by now know what a blower door is. A tool to measure the air tightness of a house. I’ve owned my Minneapolis Blower Door since 2009. Many states have adopted mandatory tightness testing on all new construction. In my area, the minimum is three air changes per hour at 50 Pascals (3 ACH50), Continue reading “Energy Audit-Advanced Blower Door Testing-Zonal Pressures”
Building Science-A Visual for Blower Door Testing
I recently tested the Code Minimum House for air tightness at the rough framing stage. We ended up where I was hoping at this first test, .55 ACH50, 140 CFM. Given the volume of the home, the leakage area is equal to approximately 15 square inches. Continue reading “Building Science-A Visual for Blower Door Testing”