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 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 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

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

We had Evergreen energy do blow-in cellulose. I was very happy with the result. They tested with blower-door before and after. House is now MUCH warmer. Also, in the time since when I've had to open walls for various access, I've been impressed with how they got the insulation packed in everywhere. I'd use them again.

Noah

Peaks Island

We needed basement encapsulation to stop moisture coming up into the house from our regularly flooding basement. We had mold growing on windowsills and furniture. All the staff were friendly, respectful of our home, and easy to work with. Humidity has gone from 70% down to 40% and mold has not grown back after two months. Very grateful.

Sarah C.

Belfast

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

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

Jennifer A

Thanks Evergreen Home Performance for helping to make our home more efficient. Many thanks as well to Bryan for the initial walk through and recommendations to make our home more efficient and to Dave, Roland, and Jacob for a job that was done professionally and courteous. We were amazed at the level of efficiency and everyday they made sure to protect our floors, carpets, and furniture. We had daily discussions with Dave about progress and what was being done and where they were at in the project.

Carol Fink

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

We had Evergreen Home Performance of Rockland come in to make our home more energy efficient, and what a TOP notch crew. Brian and his crew did an amazing job from start to finish. Very knowledgeable and professional. We would Definitely highly recommend this crew to anyone who is looking for energy efficiency in their home with a company that truly is an expert and knows how to do a quality job and truly cares about their customer.

Melissa S.

Owls Head

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

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

Great team!

George S.

Bath

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

Evergreen came back this year to finish insulating our house. We have been remodeling and renovating an 1850s cape for several years. Their employees are very professional and pleasant to deal with. Over several years Brian Robinson has been able to schedule us in for several small areas that needed addressing and finally turning a room we used to close off in the winter into a comfortable usable space. We primarily heat with wood and since Evergreens great work our furnace has only come on ONCE this winter. Fantastic. Really satisfied customer in Thomaston.

Chris F.

Thomaston

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