Can You Apply Spray Foam Insulation to Existing Walls?

So your home isn’t a new build, but you want to add spray foam insulation? Not a problem! Experts at MPI Foam can help add spray foam insulation to your existing walls for increased energy savings, temperature control, and overall comfort in your home.

Many homeowners wonder if it’s possible to add spray foam to existing walls because of its expansive nature and the process involved in insulating.

These are the steps we follow when adding spray foam insulation to existing walls:

1.    Assess the area to be insulated

First, we recommend having a spray foam expert come out and assess the area you’d like insulated to confirm spray foam insulation is the right fit. We often address crawl spaces and attics in residential homes.

2.    Determine if drywall needs to be removed

In most cases, a portion of the drywall must be removed for our team to use the sprayed applied foam method. We work carefully to make minimal cuts to the drywall for seamless installation. This approach helps us avoid the need to remove the entire wall and enables us to reach all the nooks and crannies. Insulating even the smallest areas results in excellent coverage and energy efficiency.

3.    Spray insulation, control the expansion, trim the excess

Upon installing the spray foam insulation to your existing walls, our experts use precise measurements to keep the foam from expanding too much. If you’re installing spray foam within existing walls with drywall, too much foam can cause bubbling and bend the drywall, creating cracks. Ultimately, if you don’t have drywall in place, it’s still important to be mindful of the expansion and trim any excess for a snug fit between building materials.

For our complete spray foam installation process, please click here.


How does the addition of spray foam insulation help your home?

Additionally, spray foam insulation helps improve the following:

  • Energy savings: Enjoy energy efficiency and lower bills as spray foam foams air and moisture barriers to protect your home.
  • Temperature control: Keep the draftiness and hot Carolina humidity outside for regulated temps inside for a cool and cozy summer.


Whether you’re buying a new to you house that needs more insulation or your home is due for an insulation upgrade, the MPI Foam team is here to assist.

Get a quote for insulating your existing walls today.



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