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How and Where to use Expanding Foam Insulation

How and Where to use Expanding Foam Insulation

Expanding foam is one of those products that fall squarely in the duct tape, bailing twine and WD-40 category. It has a list of uses that’s a mile long and is still growing. In fact, with expanding foam and the three other items mentioned above, TV’s MacGyver probably could have escaped from the bad guys, saved the day, and cooked dinner.

Expanding foam is first and foremost a product used for insulating and sealing cracks. The great benefit of it is that the stuff can fit into virtually any space.  With the straw applicator, use in tight areas is a snap. Some of the most common uses for expanding foam are for sealing cracks and holes around the home, such as along the foundation or in the attic. It also is a standard product for using around window and door installations. It works as an insulation (for temperature and sound-proofing) and is an effective barrier against insects and larger pests.

Some additional uses include:

  • Appling around pipes to quiet the rattle as water flows.
  • Use as an adhesive for outdoor landscaping projects such as balanced stones (stacks), waterfalls, or bird-baths.
  • Artistic sculpture, or as a medium for sculpting items and props for decorating, Halloween, Cosplay, etc.
  • Use as a packing material for extremely delicate items.
  • In vases/containers for artificial flower arrangements.

Expanding foam is notoriously messy to work with –and even more difficult to clean up if not addressed right away. There are some things to keep in mind before using the stuff, so here are a few tips:

  • It is possible to save a partially used can for later. The key is to clean the applicator properly. After you’re finished using your can of expanding foam, simply use another one of our favorite products mentioned above: WD-40. Just pull out the straw from the foam can and spray in a little WD-40. It will breakdown the residual foam inside the straw. Wipe the applicator with a rag and repeat with the WD-40 until the foam is gone.  Acetone can be used in lieu of WD-40, if you don’t have any available.
  • Make sure you wear protective clothing. This stuff is great at getting anywhere, which is not always a good thing.
  • If the foam gets on a surface that you don’t want it to, remove it immediately with something disposable such as a scrap of cardboard or a popsicle stick. Next, discard the scrap right away, so it doesn’t stick anywhere else.
  • Use acetone or WD-40 to help remove the remaining un-cured material (as long as the surface cannot be damaged by the chemicals).  Once cured, expanding foam can only be removed by mechanical methods such as sanding and scraping.
  • For larger projects, consider picking up a dispensing gun. It gives much greater control during application, reduces fatigue, and reduces the likelihood of messes.
  • Know which type of expanding foam you are using. It is available in varying degrees of expandability, so some are suited better for specific projects. For example, too much expansion is not good around windows and doors because it can affect the operation of the unit.