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Building Science

Bonus Room- Floor of Room over a Garage

One of today's most popular home features is the bonus room over the garage or porch that's often converted into a media room or extra bedroom. They offer great functional space, but are often uncomfortable. In cold climates, floors can be 10 degrees F cooler than the room.

What's the problem?
  • It's almost impossible to keep conventional fibrous insulation in contact with the floor above (when insulating the garage ceiling)
  • Due to voids and air spaces, fibrous insulation may not perform to its rated R-value
  • Gaps in the insulation allow exterior air, exhaust fumes and odors to penetrate from the garage or exterior 
What can you do?
  • Insulate the garage ceiling (underside of bonus room's subfloor) with an insulation/ air barrier system like Icynene to minimize air leakage, potential condensation problems and air quality issues
  • Make sure temperature-sensitive utilities, such as water pipes, drains, or ducts, are kept within the insulated, conditioned space 

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I am SO glad I decided to use Icynene to insulate the entire envelope of my house. We did a full-renovation, and the 100% air barrier has been fabulous. Ameri-spec tested our house for the federal renovation grant, and said we were more heat efficient than most of the new "green" homes going up on the west side. Icynene definitely contributed to the $3800 rebate we got.
Tim, South Lethbridge