How Insulation Works

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If you own a house in Coastal Maine, then you probably understand how difficult it can be to keep it comfortable throughout the year. Many homeowners in the region have to crank up their heating systems all winter long, only to keep the windows open all summer in order to stay cool. This makes insulation an especially valuable home investment here in Maine, as it can keep heat in during the winter and then block heat during the summer.

Have you ever wondered how insulation regulates indoor temperatures year-round? Here is a brief look at how insulation works.

How Heat Travels

Insulation is all about controlling heat flow. In order to understand how insulation works, you first have to understand how heat moves through your home. Heat travels in two major ways through the home: by conduction and by convection.

Conduction

Conduction refers to how heat moves through solid materials. You experience conduction when you hold a hot cup of coffee and the heat warms up your hand. You may even place a sleeve around the hot cup to keep the heat from burning your hand. This sleeve acts as an insulator to slow the movement of heat from the hot cup to your hand.

Heat can travel both into and out of your home by means of conduction. In the summer, heat may hit the roof and then travel through building materials via conduction into the attic. In the winter, indoor heat will rise and then escape through roofing materials via conduction.

Convection

Convection is the movement of heat through liquids and gases such as air. Forced air heating systems use convection to push warm air throughout a home. Even if you don’t have a forced air heating system, heat travels by convection due to stack effect — where hot air naturally rises and cooler air falls since hot air is less dense.

Though stack effect is a natural phenomenon, it can significantly undermine home comfort if your house has air leaks and is under-insulated. Air leaks and insulation gaps in upper areas of the house allow hot air to rise and escape through the roof, while air leaks in lower areas of the home pull cold outdoor air in, resulting in drafts.

The Role of Insulation

If you want to prevent heat from entering and leaving your home and minimize the workload of your HVAC systems, it’s important to insulate the areas where heat flow occurs.

Sealing air leaks eliminates holes and cracks which allow heat to travel by convection. Installing insulation, meanwhile, reduces heat’s ability to travel via conduction. The effectiveness of insulation is measured in R-value; the higher the R-value, the more effective the insulation is at reducing heat flow.

Attic insulation is especially effective because it prevents indoor heat from rising into the attic during the winter and outdoor heat from entering the home via the roof during the summer. Other areas that should be insulated include the basement or crawlspace, exterior walls, and around any air ducts or hot water pipes located in unconditioned spaces. When done right, home insulation gives you dependable home comfort and lowers your utility bills all year long.

Insulate with Evergreen

At Evergreen Home Performance, we understand what homes need to stay comfortable year-round. If your monthly utility bills are especially high, or if there are areas in your house that just never seem to be the right temperature, our experts are here to diagnose your home and create a custom insulation solution.

During an energy audit, we will locate insulation gaps and air leaks that are undermining home comfort. Then, we will install high-performance insulation materials such as spray foam, cellulose, and mineral wool where necessary.

Ready to find out what insulation can do for your home? Contact us or call 207-594-2244 to schedule a free consult!

We're your insulation experts.

207-594-2244

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

Great company. Very professional and thorough. They take the time to explain everything and offer options to fit your budget. Wonderful experience from start to finish.

Bonnie Eustace

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

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

I waited a year to write this review. Evergreen finished our job late last winter. Terrific results!!! we've gone from 12-day propane deliveries to 30+ day propane deliveries. The house is noticeably warmer. The Evergreen crew was/is professional, prompt, thorough, scientific, gracious and immaculate with respect to keeping our house clean. Money well spent.

John E.

Boothbay

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

Evergreen was so helpful in securing us Efficiency Maine funding for a big attic insulation project early this winter. They did all of the paperwork, and totally guided us through a vermiculite removal process that included a payment from a trust for the procedure. I could instantly feel the second floor being so much warmer than before. The boiler does not kick on nearly as frequently since they completed the job. It was worth every penny! Brian Robinson was so thorough throughout the whole process including a full walk through after the job had been completed.

Todd W.

Camden

I was very impressed by the professionalism of this company and the workers. Brian R. was very prompt in replying to my questions; the crew was meticulous in all parts of the work and attentive to the safety aspects concerning Covid; and Brian was extremely thorough in the final inspection. My attic is now snug and warm and I've noticed that the second floor is warmer as well.

Julia S.

Rockland

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

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 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 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

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

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

I highly recommend Evergreen! 1st, I had a home efficiency inspection (that was free) & Bryan P. was great! He took the time needed, asked & listened to what I thought were priorities, explained clearly what he thought were priorities & why, then gave me numerous options. No pressure whatsoever. Then I had my attic sealed & insulated as the 1st step & Bryan came along on day 1 to introduce everyone & make sure we were all on the same page. Bruce's team (inc. Kelsey & Roland) did the work - they were exceptional!!

Melissa M.

Kennebunk

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