Do I Need to Remove Old Insulation Before Installing Spray Foam?

Today, one of the best roofing solutions a homeowner can ever give to their home is spray foam. Not only is it a lot easier to apply compared to traditional roofing solutions, but it is also much more effective at insulating a home. That being said, if you are interested in insulating your attic with spray foam roofing, you must first remove old insulation solution. You might think that leaving it there is a good idea, that it will pair well with the spray foam solution. However, this isn’t the case.

Today, we’re going to talk about why you want to remove old insulation before installing spray foam:

It May Tamper with Circulation

Airflow circulation is an essential aspect of your home simply because your HVAC system’s job is to move air throughout the house. The reason it does this is to ensure that the air is properly pulled from places it needs to be pulled from, brought to the right temperatures, and blown back into the home. Any hindrance to the circulation can lead to HVAC systems working harder than they should, increasing your energy bills.

When talking about old insulation, these solutions are generally installed in places like the attic floor. This means that it could hinder any warm air rising into the attic and throughout the entire house. As such, removing this old insulation solution can promote better circulation throughout the home.

May Lead To Uneven Temperatures

Another big problem with tampered circulation isn’t the fact that the HVAC system will work extra hard to keep the home warm or cool. Rather, it would be the uneven temperatures throughout the home. For example, if old insulation is left on the attic floor in the summer, the attic itself might be blazing hot while the rest of the home is cool. This is a problem because if you enter the attic, the old insulation will make it incredibly uncomfortable to be in. For that reason, the removal of old insulation is vital to ensure the home is evenly comfortable with the treated air. 

In addition, the elimination of temperature differences also tackles problems like condensation in the old insulation material itself. Condensation can lead to mold growth in the insulation material, which can later spread to other parts of the home thanks to the buildup of moisture caused by temperature differences. In the longer run, mold can then get into the HVAC system and spread throughout the house, creating a nightmare to deal with.


All in all, the two reasons you want to remove old insulation when applying spray foam are to ensure circulation is maintained and that the home is comfortable throughout. Other problems like mold growth and the like can also be tackled by removing old insulation, ensuring temperatures are even throughout the house. That said, now that you know you should remove old insulation before installing a spray foam roof, you can start removing old insulation and enjoy SPF roofing!

If you’re having trouble eliminating old insulation or even installing new spray foam roofing, feel free to reach out to the professionals. They have the expertise and skills to insulate your home properly, and they will make sure that you get the best insulation solutions possible to create a comfortable, happy home.

American Foam Experts is a leading family-owned spray polyurethane foam roofer specializing in SPF applications for residential and commercial properties. If you are looking for residential foam roofing services in Walnut Creek, work with us today!