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

I used to spend winters in the bathtub because my house was so cold. This was my first winter roaming around my whole house comfortably. This even led me to decorate a little. My heating oil usage has been reduced by over a quarter: I rarely have to boost the thermostat because the temp stays at a constant. The Efficiency Maine rebates, together with the energy savings, make it affordable for me to pay for the loan I took out to finance the project. I do not worry about my pipes freezing.

Claire Helene Bevan

Camden

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

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

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

My husband and I bought a home on the water in Owls Head and decided to make the investment in Evergreen's recommendations for insulation. Brian Robinson spent 3 hours examining every nook and cranny before he made practical suggestions and explained them thoroughly to us.

Marie McNeely

Owls Head

From beginning to end – that is from the moment Justin McEdward stepped into our home to assess our energy conservation needs until the crew left – the Evergreen Home Performance process went absolutely smoothly. Justin made a thorough inspection and took pictures with an infrared camera. His proposal described the scope of work in detail, and he explained what we could expect the proposed work to accomplish. Our proposal was forthcoming within a couple of days, and Justin was available to discuss it and answer questions.

Adrienne Harkavy

Evergreen completed the work at my home thoroughly and professionally. An inspector from Efficiency Maine came to inspect afterwards and described it as "state of the art" and "outstanding". The crew was very pleasant and considerate during the project. Their cleanup each day was perfect. Communications with the office were easy and reliable. I am very satisfied.

Catherine H.

South Portland

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

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

My experience with Evergreen was excellent. From their thorough and thoughtful initial consultation to their detailed post-work visit, the team was professional, knowledgeable, and responsive. Their workmanship was top notch. Our home is now much warmer and more efficient. I highly recommend their services!

Douglas R.

Edgecomb

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

Update 12/2018: Evergreen has completed Phase II of my house (insulating and installing air/moisture barrier on exterior walls, replacing old windows) and now that heating season is upon us, the difference is astonishing. The house is tight as a drum and so easy to keep warm. Worth every penny. Thank you all! Working with Evergreen was a positive experience from start (no charge energy audit) to finish (a MUCH more comfortable home). Brian Robinson spent a lot of time with me on the audit, explaining clearly what he was finding in my ca.

Rebekah W.

Rockport

I never leave reviews, but had a great experience with Evergreen and wanted to spread the word! In short, we worked with them to insulate our roof this winter and have noticed surprising immediate results. The constant ice dams I have wrestled with are completely gone, and the home is noticeably more comfortable. It's a little too early to tell if our oil bill is going to reduce, but I imagine we will see an impact there as well.

Joel W.

Portland

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

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