Air Sealing and the Stack Effect

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Sometimes building science just isn’t fair. It doesn’t care how much insulation you buy, or even how hard you work installing it. Nooooo, the laws of physics insist that your house is a system, and that insulation can only do its job when it goes hand in hand with air sealing.

To understand why, you need a little building science background. Air moves through small pathways in your home’s walls and ceilings thanks to the stack effect. This movement has more to do with pressure than with temperature, so the stack effect plays out differently depending on the season. In the winter, cold air sneaks in through the foundation walls and rises up and out through the attic, taking the heat you’ve paid for with it.  In the summer, the stack effect pullswarm air from the attic into your home as cool air escapes through foundation leaks. Building science isn’t fair, remember?

As long as air is leaking through your house, the stack effect is wasting energy, making you uncomfortable, and costing you money. That’s why comprehensive home performance starts with something you’ll never see: air sealing. At Evergreen, we caulk, foam, and plug plumbing chases, wiring penetrations, and inexplicable holes to slow the stack effect and ensure that insulation does its job.

Take that, building science.

Track down the hidden pathways behind the stack effect in your home with a FREE infrared scan from Evergreen Home Performance and learn how strategic air sealing can improve the comfort and efficiency of your whole home.  Contact us today and learn how long-term, low-interest PACE or Energy loans from Efficiency Maine make home energy efficiency projects easy and affordable.

Contact us today to learn more!

207-594-2244

We just finished a large project of air sealing and reinsulating our 1890s basement and attic which had been completely renovated 8 years ago but still felt cold and lacked proper energy assessment and corrections. We met with Justin in December and were very impressed with his knowledge, professionalism and communication skills and knew Evergreen was who we wanted to work with. Dave was our on hands project manager and was excellent. The office staff has been quick to respond and helpful as well when needed.

Emily Gallant

Evergreen removed and replaced the insulation in my attic. They did a great job!, Crew was excellent, and the whole thing went smoothly, and the attic was NOT easy to get into or work in, so kudos to some hard work done well!

Joel A.

Portland

I waited a year to write this review. Evergreen finished our job late last winter. Terrific results!!! we've gone from 12-day propane deliveries to 30+ day propane deliveries. The house is noticeably warmer. The Evergreen crew was/is professional, prompt, thorough, scientific, gracious and immaculate with respect to keeping our house clean. Money well spent.

John E.

Boothbay

Last week, my oil company asked if we were using some other kind of fuel because our usage was so much less than they had expected We are very happy with the results; the house is much more comfortable

Steve T.

St. George

"Working with Evergreen from start to finish was a great experience." See what our customers have to say about their experience with Evergreen Home Performance. 

Jeff L.

Awesome company. It was a few years ago that they did the audit and then we commissioned them to do the work. We subsequently sold our house and moved to South Africa, but their level of service and expertise will live on.

Odette Brown

I was extremely pleased with the professionalism and quality of service that I received from the Evergreen team. I met Richard to discuss options for insulation. I knew immediately that I wanted to do business with them because he did not try to over-sell extra services that I did not need. Dave was the project manager. He was not only kind, but very respectful of my home. I would highly recommend this company.

Darlyann M

Bath

Evergreen did a fantastic job insulating our 1930's home. The onsite team was professional, clean, and really just a joy to interact with throughout the process. A blower test at the end showed a significant decrease in air leakage. I highly recommend Evergreen.

Kristen H.

South Portland

I made the mistake of NOT hiring this company last year when I bought and renovated my home. I have brought them in now and what a difference. This group knows what they are doing. They take a complete look at everything and believe they can make your home more energy efficient. They are very professional in the way they approach problems and solutions. And they find ways to save me money. Don't bother with anyone else. Bring Evergreen in before you do anything. Let them assess your issues and give you the right solutions.

Shaw

Owls Head

From start to finish, our experience was incredible. Justin was extremely helpful. The crew was fast, friendly, and efficient. And most importantly, our home is WAY warmer and our heating is less costly. I'd highly recommend evergreen to anyone looking to upgrade their home!

John S.

South Portland

Evergreen did everything they said they would and more. I actually don't mind going into the basement now since they sealed it. The air quality in the house is noticeably better and it's warmer in the winter. We can even store clothing down there where before, whatever was in there would mildew. Even the spider population declined! I used to vacuum so many of them from the corners of the ceilings in the house. Not any more!

Loriel Van Dusen

Highly recommended. Our heating usage is now less than half what it was before we had our roof insulated. Evergreen was knowledgeable, friendly, and left no trace they were ever in our house. Not only is our heating bill much lower now, but our home is generally more comfortable year-round with less temperature fluctuations. Money well spent.

RC Lations

The Evergreen Team did a fabulous job, well exceeding our expectations, In just over a week they transformed our very drafty, noisy 213 year old house into a snug, draft-free, quiet haven with warm floors! The team was prompt, did everything they said they'd do and more. We are thrilled!

Trudy M.

Bridgton

I am very pleased with my experience with Evergreen Home Performance. I met several times with Richard Burbank and he was very detailed in his explanations to all of my questions. He provided me with several options for improving the insulation to our home. The team of installers were very professional and respectful of our home. They did a great job of cleaning up every day after the days work and they were also very responsive to all my questions as well as we collaborated to get our home better insulated. It was a pleasure to work with Richard and…

Brian C.

Falmouth

The Evergreen Team did a fabulous job and was very tuned and responsive to the particular needs we had. The job was done right on budget and we are thrilled with the improved warmth and energy efficiency.

Ira M.

Rockland

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