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 couldn't be more pleased with the easy, professional, high-value service from Evergreen. Having purchased an older home that had been in our family for generations, we needed multiple upgrades, including insulation throughout. Evergreen insulated our attic with blown-in cellulose, built a new, super-insulated attic hatch, sealed off the old one (which was just a piece of plywood in a closet ceiling), and also talked us through our best options to upgrade our heating system given the plans we have to add onto the house.

Tom G.

South Thomaston

We are thrilled with the job Evergreen did to transform our 213 year old home into a warm, draft-free, cozy space. The entire team led by Bruce was prompt, courteous, knowledgeable, and hard working. If Evergreen could transform our home in this way, we are sure they would make a comparable difference in YOUR home!

Jonathan M.

Bridgton

The team members were very professional, worked very hard, paid very close attention to detail and cleaned up meticulously every day. I really appreciated the care they took knowing the smallest details were going to make a big difference to our heating bills. Thank you!

Pam B.

Brunswick

Great team!

George S.

Bath

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

Evergreen is a terrific company to deal with. Polite and efficient crews, meeting deadlines and major reduction in our heat bills. They corrected a lot of issues we suffered from doing work with a shoddy building contractor. We would recommend them to anyone.

Mary Carey

The folks at Evergreen did a great job fixing a rather major insulation problem in my house, which they helped identify with a great audit. When the work began, they were thorough, upbeat, and -- dare I say it -- efficient. I strongly recommend them.

Michael Williams

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

We had Evergreen redo the insulation in our roof. The team handling our project did a great job. They left the house spotless. We've already noticed the difference in how much better our house is retaining heat. I would definitely recommend and will use them for future projects.

Ffej C.

South Portland

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

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 cannot say enough great things about working with Evergreen Home Performance. Everything including the initial consultation, the fabulous work crew, the office support and the final resolution was handled in a caring and professional manner. My only regret is that I did not know about them earlier. I enthusiastically recommend Evergreen to anyone with concerns about home energy use.

Darlene R

Bath

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 very impressed by the professionalism of this company and the workers. Brian R. was very prompt in replying to my questions; the crew was meticulous in all parts of the work and attentive to the safety aspects concerning Covid; and Brian was extremely thorough in the final inspection. My attic is now snug and warm and I've noticed that the second floor is warmer as well.

Julia S.

Rockland

I had gotten estimates from several other companies, but Evergreen was in another league entirely with their professionalism. If you want the job done correctly, I couldn't recommend this company enough.

Rayna Mayo

Freeport

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