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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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With Icynene in our townhouse, our energy bills are 35% less than our neighbors who used fiberglass. And with the addition of an air filter, our son is having less asthma attacks.