What are the eco alternatives that will seal out water, mice & all?! My contractor has been using spray foam to seal holes between pipes.

Asked by pamela weymouth
Mill Valley, CA

I've heard that cotton is one option, but is there something just as durable & effective as the chemical stuff for sealing around pipes? thanks-Pamela from Mill Valley CA


Danny Kelly

Answered by Danny Kelly

Charlotte, NC

Kelly McArdle Construction

August 24, 2011

When sealing around pipes and other holes in your home, the main purpose for this is to keep air from moving through the holes.  Water and ice are secondary to air movement.

  • Since air is the priority, anything that will allow air to pass through it is not a very good product for sealing holes, this would include fiberglass and cotton.
  • Spray foam is the most common product for sealing holes, as it expands it fully seals all holes which makes it a great product.

If you would prefer to use something else, a fire rated caulk will do an equally good job but you must pay close attention that all holes are filled completely.


For more information:

Read "Should we insist that our contractor use expanding foam insulation around our new windows?" a Q&A answered by Carl Seville.

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