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

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

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

Evergreen is the "go-to" company for improving the efficiency of your home. There are others to choose from but none so effective, honest, and capable as Evergreen. They did a great quantity of dense packing cellulose to improve our home (both for energy efficiency and for sound insulation) and it was totally successful. They are on-time, helpful, and caring. They clean up to a level that can't be over emphasized. This was the second time we employed them and we'd use them again if the opportunity came. You'll not be sorry to select Evergreen.

Dirk F.

Belfast

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

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

Working with Evergreen was a dream! Professional, knowledgeable, and super clean work. Communication was fast and service impeccable. The bedroom floors in our 1960's split ranch will be warm with the new insulation between them and the garage. Bring on the snow! (not really, but sort of)

Jess Dee Proctor

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

The crew members from Evergreen Home Performance each made sure to greet us every day, while maintaining their distance in this time of the pandemic. Their work took a total of nine days, spread over three weeks. Even though they were working in multiple rooms of our house, as well as the basement and attic, they were unobtrusive and always cleaned up after themselves every day. The on-sight manager kept us informed of their daily schedule so we'd know which parts of the house they'd be working on.

Bob & Sue

Whitefield

Thorough, smart, informative, integrated, and communicative -- that's how my experience was with Evergreen even with the covid interruption midstream. The team picked up where they left off, insulated basement and air sealed attic and knee wall in 100' temps under the eaves! This business group was a pleasure to work with.

Karen W.

Gray

Evergreen has insulated two homes that we've owned now and both times we experienced exceptional service and craftsmanship. Our rep, Justin, went above and beyond answering questions and the installation team was attentive to every detail, including pulling out old poorly installed insulation and redoing a bathroom fan that wasn't up to current code. They also left the place spotless every day! Our home is already so much warmer this fall and we are looking forward to using less oil this winter.

Eva G.

Falmouth

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

I had gotten estimates from several other companies, but Evergreen was in another league entirely with their professionalism. If you want the job done correctly, I couldn't recommend this company enough.

Rayna Mayo

Freeport

Evergreen has just completed Phase 2 of 2 at my home. They are professional, hard-working and courteous. They communicate well..no surprises. They've gone above and beyond to make my home comfortable and were very respectful of my home.I recommend them unequivocally!!!Many thanks to Brian, Brian, Rick, Eddie, Dawson and the rest of the Evergreen crew!!

David Henry Feldman

A thorough inspection of our (older) house and its energy needs. Competent and personable work crew.

Jacob Watson

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

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