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.”

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We absolutely loved our experience with Evergreen. The team was incredibly kind, professional and great to work with. We're very impressed with the quality of work of the Evergreen team and how easy they made everything! Our house had barely any insulation ahead of this project and the results are amazing. Insulating the attic, walls and basement with Evergreen allowed us to tear a 50-year-old furnace, ductwork and oil tank out of the basement and now heat the home with new heat pumps. Evergreen also added 100 sq ft of clean, new storage space to the attic!

Nick S.

South Portland

The Evergreen crew from initial inception to installation were professional, on time, and left our place spotless. The end result was exceptional.

John Brown

We just finished a large project of air sealing and reinsulating our 1890s basement and attic which had been completely renovated 8 years ago but still felt cold and lacked proper energy assessment and corrections. We met with Justin in December and were very impressed with his knowledge, professionalism and communication skills and knew Evergreen was who we wanted to work with. Dave was our on hands project manager and was excellent. The office staff has been quick to respond and helpful as well when needed.

Emily Gallant

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

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

Our house still the most efficient home we’ve ever lived in. And we have you folks to thank for that! A special howdy to Brian Robinson please!

Bruce O’Donal and Eva Butler

The Evergreen crew who installed insulation in my attic were fantastic! They were very professional, worked exceedingly hard, and they did an excellent job. They were very pleasant and friendly to be around. They cleaned up beautifully after each work day, and left my home in great shape on when they walked out the door for the last time. I can't believe they were able to accomplish all that they did with heat soaring into the 80s and 90s. It was pretty unbearable up there! They have my highest praise and my gratitude.

Cynthia F.

South Portland

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

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

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

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

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 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 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

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

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