Spray Foam Insulation Upgrade is Perfect for the Older Home

Older homes have character, charm—and often—air leaks, drafty rooms, and sky-high energy bills. At Custom Insulation Company, Inc., we specialize in helping homeowners bring their historic or aging homes up to modern energy-efficiency standards without sacrificing their unique appeal. One of the best solutions? Spray foam insulation.

Spray foam is incredibly versatile, making it ideal for retrofitting insulation in hard-to-reach or problem-prone areas. Here are the best places to use spray foam insulation in an older home:

1. Attics & Attic Rafters

Attics are one of the biggest sources of energy loss in older homes. Spray foam can be applied directly under the roof deck or between rafters to create a tight thermal seal. This not only prevents heat loss in the winter but also keeps hot air out in the summer.

Pro tip: Spray foam helps regulate temperature and prevents ice dams in colder climates.

2. Basements & Rim Joists

The rim joist—the area where the foundation meets the wooden structure—is a common source of drafts and moisture infiltration. Spray foam seals this vulnerable gap, helping to improve comfort and prevent mold growth.

Bonus: Helps keep basements drier and more comfortable year-round.

3. Walls (Especially Uninsulated or Poorly Insulated Ones)

Older homes often lack adequate wall insulation. Spray foam can be injected into wall cavities through small holes, making it a minimally invasive way to upgrade insulation without major demolition.

Result: Improved indoor comfort, less outside noise, and better energy savings.

4. Crawl Spaces

Crawl spaces are notorious for bringing in cold air and moisture. Closed-cell spray foam insulation acts as both a vapor barrier and an insulator, protecting your home from below.

Tip: Combine spray foam with crawl space encapsulation for best results.

5. Behind Knee Walls

In Cape Cod or bungalow-style homes, knee walls (short walls under sloped ceilings) often have little to no insulation. Spray foam seals these small, oddly shaped spaces efficiently.

Why it matters: Helps prevent uneven room temperatures upstairs.

6. Around Windows, Doors & Plumbing Penetrations

Even if the rest of your home is insulated, small gaps around windows, doors, and pipe entries can lead to major heat loss. Spray foam expands to fill these gaps completely, stopping air leaks cold.

Result: Less draft, lower utility bills, and a cozier living space.

Why Choose Spray Foam for Older Homes?

Older construction wasn't designed with modern insulation in mind. Unlike traditional materials like fiberglass or cellulose, spray foam expands to fill gaps, seals air leaks, and adds structural strength. It's also ideal for irregular spaces and tight areas that are common in older buildings.

Trust the Experts at Custom Insulation Company, Inc.

Retrofitting an older home with spray foam insulation requires precision and experience. At Custom Insulation Company, Inc., we’ve been helping homeowners across Massachusetts and beyond upgrade their comfort and energy performance for decades.