Spray Foam Insulation in Bethesda, MD

Spray foam insulation in Bethesda often happens during renovations. A streetcar line arrived in 1890 and suburbanization picked up in the early 1900s, with subdivisions such as Drummond, Woodmont, Edgemoor and Battery Park laid out on old farmland. Many of those houses have since been expanded. The 2020 census counted 29,547 housing units in the CDP, 5.9 percent vacant.

Additions and renovations

When walls and ceilings are open, closed-cell or open-cell foam goes into stud and rafter bays, sealing as it insulates. Additions often include bonus rooms, finished attics and vaulted ceilings, where foam on the roof deck fits well.

Older houses

Colonials and Tudors from the early and mid 1900s need the usual: attic air sealing and depth, rim joist foam, and basement walls if the space is being finished.

Code

Maryland adopted the 2021 IECC effective May 29, 2023: R-49 ceilings and R-20 or R-13+5 continuous walls in Zone 4. Montgomery County is in Zone 4A.

Older homes that stay as they are

Not every Bethesda house is being expanded. For a 1930s or 1940s colonial staying as is, the most effective work is usually attic air sealing, topping up insulation, rim joist foam and, where there is one, the crawl space under a sunroom or family room addition.

Written quote

Each area gets its own line with the material, thickness, R-value and price, which helps when you are comparing bids or coordinating with a builder.

Ducts in attics

Many larger houses have second-floor HVAC in the attic. Foaming the roof deck brings it inside. Get a free estimate