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

I would recommend Evergreen wholeheartedly because of their professionalism, their follow through, and thoughtful project planning.

Jennifer A

First we have Evergreen do a BIG project worth about $20K (windows, basement, insulate & rebuild an entire wall, a door, attics, and air sealing). They were so great we had them come back later when we decided we did want to do our other door. They are professional and do great work. They take care of your home and are trustworthy, and on top of all that friendly! I highly recommend you call them!

Garreth C Debiegun

Led by Brian Robinson, the Evergreen Home Performance team just completed an insulation refit at my home. It was truly a great experience from start to finish, a period of time that was a fraction of the time that I originally anticipated due to the team's unbelievable work habits and professional knowledge of their tasks. As impressive were the communication skills and friendliness of each and every member of the team.

Anne W.

Rockport

I cant say enough about this company and the benefits that it created for our family. They are very professional and have effectively re-insulated our home. The heating bill proves the point.

Bob O.

Springvale

Evergreen did a fantastic job replacing 28 windows in our house. They were friendly, courteous, and very detail oriented. Brian did a great job planning, estimating and executing the project. Our energy use has dropped significantly since the work was done.

Alex B.

Kittery

Several years ago Brian Robinson evaluated the crawl space at my summer home on Islesboro where I knew moisture was becoming a problem. I had done quite a bit of work in the space many years prior with mixed results. When Brian offered some suggestions, they were ideas that incorporated work previously done, and would be a relatively low cost effort to improve the situation. He offered this advice over several phone conversations of some length, informally, and at no charge.

Cliff R.

Islesboro

Bryan, Dave and the entire Evergreen team are wonderfully professional, prompt and thorough. I enjoyed working with them and look forward to continued work as we upgrade our home! Thank you so much for your professionalism, fairness, time and diligence.

Cait

Yarmouth

Evergreen did an amazing job insulating our historic home. Their professional staff worked hard to ensure the tough areas in the attic were covered, and clearly communicated their progress. We are seeing the results with our discounted heating bills. Thank you, Evergreen!

Melissa Knoll

Portland

Working with Brian and with Nate and the rest of the crew was a pleasure. They made everything very easy and understandable. This was a major renovation and they were always at the ready with a lot of information. We had an extensive renovation on the basement which was a dirt basement and it came out beautifully. We can already tell from all of the insulation work what a difference it's made in sound and temperature. Brian worked with me on the rebates that are available when you do this kind of work. I would highly recommend this company to…

Valerie L.

Rockland

Evergreen Home Performance shows its expertise from start to finish. Evergreen did three house projects in winter/spring/summer 2020 for me, attic insulation, crawl space under a porch insulation, and basement foam/vapor barrier. From my initial discussion with Bryan, I understood the reasons for choosing different types of insulation, the associated costs, and time estimates. Evergreen scheduled in advance, came when they said they would, and the crews were highly professional in their work and demeanor.

Iris S.

Portland

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

We initially contacted Evergreen through Efficiency Maine for an energy audit, which was conducted promptly and professionally by Justin McEdward, one of their Energy Advisors who is BPI-certified. After a thorough inspection of our newly purchased home, Justin explained in great detail what we needed and did not need. It was agreed that Evergreen would remove all of the existing attic insulation, which was not adequate, and replace it with blown in cellulose, to a rating of R-60.

Thomas W.

Scarborough

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

Working with Evergreen was a dream! Professional, knowledgeable, and super clean work. Communication was fast and service impeccable. The bedroom floors in our 1960's split ranch will be warm with the new insulation between them and the garage. Bring on the snow! (not really, but sort of)

Jess Dee Proctor

Evergreen came out 2 years ago to do an assessment and insulate our roof. This year we had them come back and do the basement as well. They are hands-down the best crew we've ever hired to work on our house. They are experts at what they do, and super meticulous in their work. After working in our house for a week with blown insulation, there was no trace they were ever here. We've seen a huge decrease in our energy bills while at the same time the house has become way more comfortable. Can't recommend them enough.

RC Lations II

Portland

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