A New Tool to Find Air Leaks in Buildings Using Sound

Testing the air barrier or air control layer of a home has traditionally been done using artificial pressure created by a fan, commonly referred to as a blower door test.  Why You Need Blower Door Testing – Northern Built   The advantage of using an air pressure differential testing is twofold, we can quantify the building tightness (CFM50, ACH50 or CFM/ft² of surface area) and locate deficiencies in the air barrier.  Finding the air leaks can be done by watching for fluttering drapery or spiderwebs, feeling for air leaks, using synthetic smoke created by smoke generating tools, by thermal imaging, or measuring pressure differentials between spaces inside the building enclosure using a manometer.

Continue reading “A New Tool to Find Air Leaks in Buildings Using Sound”

Considerations When Adding Exhausting Equipment to an Existing Home

I was recently contacted by a friend who wanted to add a kitchen range exhaust hood to their 100-year-old home.  They were looking for insight on how the fan might be added, where the ducts could be located, sizing of the system, and any other concerns that might need to be considered.   One of my first questions was what equipment was presently used for space heating and water heating.  A critical question that needs to be considered before adding any type of exhaust system.  Why?  Health and safety of the occupants. Continue reading “Considerations When Adding Exhausting Equipment to an Existing Home”

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.

Continue reading “Blower Door Testing for Contractors, Should You Own One?”

What is a Blower Door Test? An Introduction.

This blog post first appeared on the Andersen Windows ProViews Blog

We’ve known for a few decades that improving the air tightness of a home and installing a properly designed mechanical ventilation system can greatly enhance the performance of a home.  Having the ability to verify the airtightness of the structure is key, we perform verification by using a tool called a blower door.  This introductory blog will answer the questions; what is a blower door test?  Why do we perform blower door testing?  How is the test performed?  How do we interpret the test results?  What else can a blower door be used for?  Are there codes relating to blower door testing?  Before we dive into those questions, let’s start with that first question, what is a blower door test?

A blower door test is a test to confirm the continuity and integrity of a structure’s air barrier.

Continue reading “What is a Blower Door Test? An Introduction.”

An Airtight Home, What Do the Blower Door Numbers Mean?

I recently had the opportunity to attend a BS and Beer meeting in Kansas City, MO where the meeting took place in a home under construction.  The home was being built by Aarow Building (Jake Bruton) of Columbia, MO (they recently opened an office in Kansas City).  The home is a single level, slab on grade with around 3,250 square feet.  At the time of the meeting, the home was just finishing the mechanical, electrical, and plumbing systems and about to move to the insulation phase.  A perfect time for a mid-build blower door test.

The purpose of a mid-build blower door test is to confirm that the home is on track to meet the air tightness metric (Jake informed me that all his new homes are contractual bound to achieve 1 ACH50 or less) and to find any missed opportunities in the air sealing of the home.  The mid-build testing can be simple, get the home to negative or positive 50 Pascals of pressure and record the CFM rate, this type of testing is called “single point”.  If you feel the CFM rate (or the calculated air changes per hour at 50 Pascals number) is too high, set the fan on “cruise control” and go find the air leak locations.  There’s no need to perform multi-point testing this early in the build, (a type of blower door testing where CFM rates are measured at progressively lower pressure points, usually starting at 60 Pascals), save that type of testing for the final blower door test. Continue reading “An Airtight Home, What Do the Blower Door Numbers Mean?”

Energy Audit-Blower Door Testing a Barndominium

This post first appeared on the Rockwool R-Class Website

The first time I visited one of Kyle Stumpenhorse’s (RR Buildings) jobsites was in December of 2022.  I made the trip to Illinois to blower door test one of Kyle’s Barndominium projects, the project he calls “Building a Barndominium”.  The barndo we tested was post and frame construction using closed cell spray foam (CCSF) as both the insulation and air sealing for the project.  The home tested very well, 0.41 ACH50.

Kyle (Left), Dan Edelman from Rockwool (right), and me at Kyle’s first blower door tested barndominium, December 2022.

I got to know Kyle a little on that trip, I was very impressed by his attention to detail and willingness to learn.  He pushes himself to do better on every new build.  I wasn’t surprised to find out his next project he was planning on using Rockwool insulation.  He also had a goal, beat the blower door score of the project using closed cell spray foam as the air barrier.  Could it be done?

Continue reading “Energy Audit-Blower Door Testing a Barndominium”

Code-Blower Door Testing a Small Home

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”

Recessed Lighting in Older Homes-The Issues and the Fixes

The post originally appeared on the Green Building Advisor Website.  

Recently, I’ve been on a few energy audits and assessments where the homes were built or remodeled in the late 1990’s and early 2000’s.  Electricians working in those times were installing the traditional recessed light fixtures, also known as recessed cans or pot lights.  This type of lighting fixture usually doesn’t have any issues when installed inside the air and thermal boundaries of the building envelope but can be very problematic when they end up displacing insulation and interrupting the continuity of the air control layer.  I’m going to discuss the pros and cons of this type of lighting as well as how we can improve the performance of a home that has existing recessed cans.

Continue reading “Recessed Lighting in Older Homes-The Issues and the Fixes”

Barndominium-Mechanical/Electrical/Plumbing and Final Blower Door Numbers

This post first appeared on the Green Building Advisor Website.

Work on the “barndominium” project is nearly complete after 18 months of construction.  You can read parts 1-5 here on GBA (linked at the bottom of this post) and on this blog, links to the right labeled Barndominium Project.  This final post will discuss mechanical systems, blower door numbers, along with the challenges and benefits of this type of building method.

Continue reading “Barndominium-Mechanical/Electrical/Plumbing and Final Blower Door Numbers”