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Serving New Haven, Old Saybrook, New London, and surrounding shoreline communities

Crawl Space Insulation Services in Connecticut

Cold floors? high energy bills? Get your free crawl space insulation estimate with clear, upfront pricing.

Takes 30 mins
Zero Obligation
Same Day Quote
4.8 Customer Rating
EnergizeCT Insulation Installers Network
Licensed & Insured
Clean crawl space with insulated ceiling, exposed ductwork, concrete block walls, and a small window.
Empty dark crawl space with exposed wooden beams, concrete block walls, a small window, and ductwork running along the ceiling.

Your Crawl Space: Small Area, Massive Impact

The Benefits Insulating Your Crawl Space

Bare legs wearing beige slippers with bows sitting on a light textured rug beside a beige cabinet and a bed.
Person holding an energy statement with a large red 'PAST DUE' stamp on it.
Wooden floor joists partially filled with yellow fiberglass insulation, with reflective foam board insulation on the sides.
Empty basement with concrete floor, exposed wooden ceiling beams, and insulated walls.
Man in a white shirt crouching outside a house, inspecting an open crawl space door near the foundation.
White teardrop-shaped humidifier emitting mist placed on a wooden stool with hands adjusting a black knob nearby.
Relaxing bathtub scene with a wooden tray holding an open book and a cup of tea, surrounded by lit candles and a hanging green plant.
Takes 30 mins
Zero Obligation
Same Day Quote

What We Insulate

Every zone in your home loses heat differently. Nealon matches the right material to each area — walls, ceilings, and doors.

Rim Joists

Rim Joists

Where the floor meets the foundation. Spray foam or rigid foam board at rim joists stops air leaks and heat loss all along the full foundation line fast.
Perimeter Walls

Perimeter Walls

Insulating crawl space perimeter walls creates a space. Spray foam or rigid foam board R-10 minimum per inch for Connecticut climate zone 5
Ground Floor

Ground Floor

A vapor barrier or ground-level rigid insulation stops moisture from rising into the living space — a critical step in every Connecticut crawl space job.
Takes 30 mins
Zero Obligation
Same Day Quote

When to Insulate Your Crawl Space

Here are common scenarios when the time is right to insulate your crawl space.

Person sitting on a wooden bed frame with feet wearing beige fuzzy slippers on gray tiled floor.

Your Floors Feel Like Ice in the Winter

If your socks aren’t cutting it and your hardwood floors feel like an ice rink from November to March, chances are your crawl space is uninsulated. Warm air rises—but without a thermal barrier underneath, your heating system is fighting a losing battle.

Small gray mouse nestled among cracked walnut shells in a narrow space.

You’ve Seen (or Heard) Rodents Below

Scratching under the floor, droppings near vents, or worse—sightings of little uninvited guests? Crawl spaces are prime real estate for mice and bugs. Insulating and air sealing it makes your home way less appealing to critters.

Dark, cluttered crawl space with dirt floor, scattered rocks, wooden beams overhead, and a concrete support post.

You’re Dealing with Musty Smells or Moldy Corners

Notice that damp, earthy smell wafting up from the floorboards? That’s a telltale sign of moisture collecting in the crawl space—especially common in shoreline homes and low-lying areas. Insulation + vapor barrier = dry, clean air upstairs.

Close-up of a hand holding an energy bill with an amount due of $305.16 and details including billing date, account number, service address, billing period, and usage.

Your Energy Bills Are Creeping Up

If your heating and cooling bills are climbing but nothing else has changed, your crawl space could be a major energy leak. Insulation seals the underside of your home so your HVAC system isn’t working overtime to keep up.

Construction tools including a drill, circular saw blade, wooden plank, piece of styrofoam, and paint bucket on a dusty floor.

You’re Renovating or Replacing Flooring

New hardwoods? Upgraded vinyl plank? Before you install that fancy floor, insulate the crawl space first. It protects your investment, improves comfort, and prevents moisture from warping or damaging your new surfaces.

Crawl Space Insulation Cost in Connecticut

Your home is unique — here's what most homeowners pay, by scope.

Small Job

$2,000 - $4,000

Rim joists only

Rigid foam board or spray foam at rim joists. Fast install — stops drafts and heat loss at the foundation line.

Most Common

$4,000 - $6,000

Full crawl space, multiple zones

Walls, floor, and rim joists covered. Mix of materials tailored to your crawl space conditions and moisture level.

Full-Job

$6,000+

Full encapsulation, spray foam

Complete spray foam encapsulation with vapor barrier. Maximum moisture control and energy performance.

Takes 30 mins
Zero Obligation
Same Day Quote

Crawl Space Insulation Questions

What’s the difference between vented and unvented crawl spaces—and which should I have?

The main difference between vented and unvented crawl spaces is airflow. Vented crawl spaces allow outdoor air in, which can cause moisture and cold floors. In Connecticut, unvented (sealed) crawl spaces are better for keeping the space dry, warm, and energy efficient.

Should I remove old insulation before adding new crawl space insulation?

Yes, you should remove old crawl space insulation before adding new. Damp, moldy, or compressed material can trap moisture and attract pests. Nealon Insulation removes damaged insulation and installs new material with proper sealing for long-lasting performance.

What kind of insulation is best for crawl spaces?

The best insulation for crawl spaces is rigid foam board for walls and closed-cell spray foam for tight areas. Foam board resists moisture, while spray foam also acts as a vapor barrier. Fiberglass batts are not ideal—they absorb water and tend to sag.

How much does crawl space insulation cost in Connecticut?

Crawl space insulation in Connecticut typically costs between $2,000 and $6,000, depending on size, condition, and materials. Extra services like cleaning or mold remediation increase the price. Most projects pay for themselves through energy savings within a few years.

How long does it take to insulate a crawl space?

Insulating a crawl space usually takes 1–2 days. If the job includes air sealing, vapor barrier installation, or rodent cleanup, it may take longer. Nealon Insulation provides a clear timeline before starting any work.

Will insulating the crawl space make my home more humid?

No, insulating the crawl space won’t increase humidity. It actually lowers it by blocking ground moisture and outside air. For homes with existing humidity problems, adding a dehumidifier may be recommended for best results.

Do I still need a vapor barrier if I insulate?

Yes, you still need a vapor barrier even if you insulate. Insulation controls temperature, while a vapor barrier blocks ground moisture. Using both keeps your crawl space dry and protects your home from mold and humidity issues.

Is crawl space insulation something I can DIY?

You can DIY crawl space insulation, but it’s challenging and easy to get wrong. Mistakes like skipping air sealing or using the wrong materials can lead to wasted time and money. Professional installation ensures lasting performance and moisture control.

The Nealon Difference

Where Historic Charm Meets Modern Efficiency – Without Compromise

Historic large red brick mansion surrounded by lush green trees under a blue sky.

Older Home Specialists

As EPA Lead-Safe certified contractors, we understand the unique challenges of insulating historic New England homes.

Person using a calculator next to a small house model with a colorful energy efficiency rating scale from A to G.

Proven Energy Savings

Our customers typically see a 30% reduction in energy costs after our professional insulation services. Your investment often pays for itself through years of lower utility bills.

Two men inspecting and holding a handheld thermal camera in an indoor setting.

Professional Energy Assessment Process

Every project begins with a thorough energy assessment to identify your home's specific needs.

Takes 30 mins
Zero Obligation
Same Day Quote
Worker in protective gear spraying foam insulation in an attic.
4.8/5 Customer Rating

Reviews from our customers over 48 years

Featured Crawl Space Review

"Nealon insulated our crawl space yesterday and I am very pleased with the job. Bennett was great. Explained everything and left the job spotless. Highly recommend them."

T “Pick240” Pick

"They did great work they were in and out in no time and they cleaned up afterwards very happy with them"

 Charles Montagnon

Nealon did an outstanding job in terms of courteous services, as their team members, as well as Chris who was responsible for directing the job, were most professional!!! They cleaned up nicely, and my goods remained intact. Also and happily stated, it’s been one week since they’ve installed insulation in our home, and we notice a huge difference in the amount of energy we are using for heating…which equates to $avings!!! In short, we’d use them again, and glad we chose them for this endeavor!!!

Dia CJW

Highly recommended. Their estimate was competitive, the work was done in a timely and clean manner, they explained what was done, and our house is warmer as we head into the winter. When we had a question, they came back out to talk with us and helped us answer our questions. I will use them again and recommend them to anyone.

Ariyanakylstram

They are an amazing company to do work with! Jen in the office is polite, pleasant, and very competent. The work was done well and very quickly. We had our attic and basement insulated. I would 100% recommend!

Timothy Saunders

The Nealon team was professional and considerate of my property. I noticed a 200-kilo watt decrease in my electric bill along with an additional savings in oil consumption of 50 gallons. No more drafty cellars and so far, the mice have gone elsewhere.

Christine

Fast, efficient and great price! Didn’t even notice them insulating our attic and making a big difference already! Would highly recommend for anyone that wants to cut down on their energy bill!!

David Chase

Great experience! Very friendly and professional. They were on time, stuck to their quote and work timeline and have done a great job with two projects for me. I would definitely recommend.

Tom L

Nealon Energy Solutions has been my go to company for my personal property energy solutions & savings and all of my residential remodeling projects. as a remodeling contractor myself, I take pride in utilizing quality trades people, using quality products that perform at the top of their game. Nealon has the depth of experience that is in my opinion unmatched in the CT business market. Clients appreciate the thorough explanations of the options available to them, the professional execution of the contracted work and the cleanliness of the project when the work is completed. GO NEALON!!

Jonathan Knight Remodeling

Ready To Start Saving?

Schedule your FREE home energy assessment today. No pressure, no obligation— just expert advice for your home's needs.

4.8 Customer Rating
EnergizeCT Insulation Installers Network
1500+ Homes Upgraded
Licensed & Insured