Can spray on insulation be safely applied as a retrofit to an occupied home?

Asked by Don Keith
Fairbanks, AK

1940s construction wood frame house, peaked roof , open attic with existing wood shavings insulation. External temperature vary from -35 to + 35 C. Home is occupied. I am concerned with the safety issues re off-gassing both during and after installation. Also opinions on the relative safety and efficiency of eco (soy based) foam and PUFI systems.


Bill Bradbury

Answered by Bill Bradbury

Smithfield, UT

Envirocon Home Restoration

January 31, 2012

It depends. I use Roxul in nearly all of my retrofits now.

  • Seal every air leak,
  • install roxul
  • then install an interior vapor barrier.

Every hole in the vapor barrier must be sealed so warm moist inside air can not condense on the exterior sheathing.

Check the Cold Climate Housing Research Center for more info about high performance building for your area.


For more information:

Read "Do you recommend bio-based soy foam insulation?" a Q&A answered by Andy Ault.

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