Can a house be too tight?

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Air Sealing with Caulk Gun | Evergreen Home Performance | Maine Sometime during your crusade to seal those energy robbing cracks and holes in your home, you’re bound to start asking yourself, “Isn’t air flow important for a healthy home? Can I take this whole thing to the extreme?”

The answer is yes.  But probably not.

The EPA recommends a rate of .35 ACH (natural air changes per hour — that is, just over 1/3 of the air in your home being replaced every hour; or 3 hours for a full air change) for healthy indoor air quality. The average home has a much higher rate of natural air infiltration, and an older, leakier home will probably exceed this standard even after significant air sealing efforts.

But a leaky home provides no assurance that indoor air pollutants like dust and mold will be properly eradicated: during periods of calm weather with no wind, for example, air can sit stagnant in a leaky home for days. On the other hand, during a windy day in the winter, a leaky home effectually needs to be re-heated from scratch every few hours, which is a waste of both energy and money. The best way to ensure that a home is healthy, safe, and energy efficient is to air seal the home as well as possible, and to pair air sealing efforts with increased mechanical ventilation to make sure that air cycles in and out of the house at a healthy and consistent rate.  The mantra is “seal tight, and ventilate right.”

Contact us today to learn more!

207-594-2244

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 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

We had Evergreen come out to our tiny old (100+ year old) house to see what they would recommend for decreasing our carbon footprint, saving money, and increasing our comfort in the cold season. Richard and Bryan were great to work with, patiently answering our many questions and walking us through multiple options. We could only afford to tackle a few areas this year; we ended up replacing some windows and having them weatherize the entire house.

Alan M.

Falmouth

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

Great job installing windows and insulation.

Bob S.

Rockland

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

In the final stages of selling our home, and with a closing date set, an inspection came across an unanticipated issue in our attic. We quickly called in contractors, but nobody was able to identify the source of the problem. Then we thought of Evergreen. Brian Robinson was on site the next morning and immediately identified the source (a faulty roofing job completed three years earlier which had effectively sealed up portions of the ridge vent and restricted air flow - not easily visible with a quick inspection).

Robin McIntosh

Camden

Great team!

George S.

Bath

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

Really great experience from start to finish with Evergreen. They helped us prioritize what needed to be completed first, and has made a significant difference in our hearing costs already. Plus they were really friendly and considerate to work with!

Amy W.

Kennebunk

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

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

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 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

Very easy process, start to finish.  Friendly, professional, and really know their stuff.  They made some improvements to our condo and we were very happy with how it played out.  Would definitely recommend them.

Clayton Eames

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