Wall Insulation

Wall Insulation

Whether your walls are drafty, your rooms are uneven in temperature, or you just want a quieter, healthier, more energy-efficient home, Evergreen is here to help.

If you’ve got rooms that are always colder – or hotter – than the rest of the house, chances are your walls are under-insulated. It’s a common issue we see in many older Maine homes and a primary cause of discomfort for homeowners who have switched to heat pumps for heating and cooling.

From historic capes to coastal farmhouses, Evergreen provides wall insulation services in PortlandRockland and the surrounding Southern and Coastal Maine areas, helping you improve comfort and energy efficiency – without compromising your home’s character or structure.

  • Eligible for up to $8,000 in Efficiency Maine rebates
  • Over 4,500 Maine homes improved since 2006
  • BPI-certified experts using building science-backed solutions
Beautiful white house in Maine
Evergreen team member taking equipment and blown insulation hose out of truck at job site

How We Insulate Existing Walls – Carefully and Effectively

We know that preserving your home’s character is important. Many of our customers live in historic Maine homes with original plaster, woodwork, or shingle siding that they want to protect.

Wall insulation can make a big impact on your comfort and energy efficiency—but it’s also one of the more complex upgrades we do. Think of it like minor surgery for your home’s envelope. It requires the right tools, techniques, and safety protocols, including lead-safe work practices.

That’s exactly why you want a team that knows how to do this work carefully, respectfully, and completely—without cutting corners.

What’s the Best Type of Attic Insulation?

We offer a range of attic insulation materials to match your home’s needs, but in most Maine homes, we recommend:

Step 1: Precision Drilling

We make small, precise 2.5-3” access holes—either inside (often behind baseboards or in closets) or on the exterior (behind siding or shingles). These openings are just large enough to install insulation but small enough to repair neatly.

Step 2: Dense-Pack Cellulose Installation

Before we install insulation, we seal leaks with spray foam to prevent air infiltration. This critical step protects against drafts that can weaken your insulation’s effectiveness and ensures your insulation performs as designed.

Step 3: Careful Restoration

Once the insulation is installed, we patch and restore each access point, including replacing siding on exterior walls. For both exterior and interior jobs, we leave the areas caulked, primed, and paint-ready. Meanwhile, your home will be more comfortable and energy-efficient!

Wall insulation is well worth doing for comfort and efficiency and to maximize the impact of heat pumps. However much of the cost comes from restoring finished surfaces, which makes this project best coupled with other renovations if possible.

Some Victorian-era Maine homes have balloon framing, which can allow us to insulate some or all of your walls from the attic much more easily. Every home is different, and we’ll help you understand your options during your free consult.

Insulation blower hose going out a window down to an insulation truck

The Benefits of Blown-In Wall Insulation

  • More consistent comfort from room to room (especially in homes that have switched to heat pumps)
  • Warmer in winter, cooler in summer
  • Quieter rooms and reduced outside noise
  • Fewer indoor drafts and temperature swings
  • Lower heating and cooling bills
Evergreen Home Performance Team Installing Attic Insulation

Affordable Home Upgrades with Efficiency Maine Insulation Rebates

Insulating your walls is a smart investment—and it’s made easier by Efficiency Maine rebates and other incentives. When you upgrade your home’s exterior wall insulation, you can qualify for:

  • Up to $8,000 in Efficiency Maine rebates
  • Loan payments as low as $50/month through Efficiency Maine & NEIF financing
  • An additional 30% federal tax credit (up to $1,200 for insulation and air sealing)

Why Choose Evergreen Home Performance?

  • More than 4,500 Maine homes improved since 2006
  • Experts in historic and hard-to-insulate homes
  • BPI-certified professionals using the latest building science
  • 15,000+ home energy audits completed
  • More Mainers received Efficiency Maine insulation rebates with us than any other company in 2024
Evergreen Team Photo
Evergreen team smiling at each other

Book a Free Consult Today to Get Started

Whether your walls are drafty, your rooms are uneven in temperature, or you just want a quieter, healthier, more energy-efficient home, Evergreen is here to help.

We start every project with a free consult, and then move to a professional home energy audit to pinpoint exactly where your home is losing energy—and how to fix it.

It’s time you made your home more comfortable and energy-efficient. Call 207-594-2244 or contact us online to book your free consult and start your journey.

Feel whole-home comfort with the right wall insulation—we’ll guide you every step of the way.

BOOK YOUR FREE CONSULT TODAY

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

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

John Brown

I was extremely pleased with the professionalism and quality of service that I received from the Evergreen team. I met Richard to discuss options for insulation. I knew immediately that I wanted to do business with them because he did not try to over-sell extra services that I did not need. Dave was the project manager. He was not only kind, but very respectful of my home. I would highly recommend this company.

Darlyann M

Bath

Evergreen came back this year to finish insulating our house. We have been remodeling and renovating an 1850s cape for several years. Their employees are very professional and pleasant to deal with. Over several years Brian Robinson has been able to schedule us in for several small areas that needed addressing and finally turning a room we used to close off in the winter into a comfortable usable space. We primarily heat with wood and since Evergreens great work our furnace has only come on ONCE this winter. Fantastic. Really satisfied customer in Thomaston.

Chris F.

Thomaston

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 team members were very professional, worked very hard, paid very close attention to detail and cleaned up meticulously every day. I really appreciated the care they took knowing the smallest details were going to make a big difference to our heating bills. Thank you!

Pam B.

Brunswick

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

Great team!

George S.

Bath

Greetings one and all! I am writing to express my gratitude to all involved in my insulation project.  From start to finish, I appreciate the universal theme which was maintained by each and every one of you, to ensure that my home was insulated and protected from freezing pipes as if it was your home. Andrea, thanks for helping me navigate my way to the project. Nate, thanks for the thorough initial assessment and the time you took to explain this project to me, step by step. Brian, thanks for setting up my project - so happy

Michele

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

Professional, friendly and hard-working staff. The product/approach they use for insulation is top notch. We felt the difference immediately, both from added warmth and eliminating drafts. The team and management were easily available to answer our questions or coordinate meeting times. Highly recommended.

Kevin J.

Yarmouth

Great job installing windows and insulation.

Bob S.

Rockland

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

This team of individuals was professional at all times. They set up barriers that kept the dust at a minimum. They conducted an air flow audit and cut the draft circulation from the outside in half by sealing cracks. They hauled out the old insulation and replaced it with blown in insulation with an R - 60 Value. They also did the rebate paperwork so that I could get my $1500.00 rebate from the state of Maine. I highly recommend Evergreen Home Performance!

Daniel B.

Rockland

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

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Efficiency Maine
EPA Lead-Safe Certified
Building Performance Association
BPI Certified