Archive for November, 2009

Single Family Garage Separation

November 16th, 2009

garage separation 003A separation between the dwelling and a garage is a subject full of misconceptions.  “It’s a firewall….it has to have two layers of 5/8 gyp board on the garage side…., the door has to be a fire door with a closer are popular fallacies.   I can only speak for the last 20 years of CABO and BOCA requirements for separations,  but none of these have ever been required.  Here is what is required by the IRC 2006:

  1. You can’t have an opening into a garage from a bedroom.
  2. If you have duct work penetrating into the garage, it has to be made of a minimum of 26 ga sheet metal and cannot open into the garage.
  3. Other penetrations of the separation wall must be fireblocked.
  4. The garage shall be separated from the dwelling (including its attic) by ½ inch gyp board on the garage side (you could theoretically have open studs on the dwelling side).
  5. If there is a habitable room above the garage, the separation must be 5/8 gyp board (type X).
  6. The supporting structure of item 5 shall be protected by ½ gyp board.
  7. If there is a door in the separation wall, it must be either 1 3/8 inch solid wood, solid or honeycomb steel minimum 1 3/8 inch thick, or a 20-minute fire-rated door. (Wouldn’t a fire-rated door require a closer and positive latching?)

Myths & Legends, Residential Code