International Residential Code 2000
Section R309 Garages and Carports
R309.1 Opening protection.
Openings from a private garage directly into a room used for sleeping
purposes shall not be permitted. Other openings between garage and
residence shall be equipped with a solid wood door not less than 1 3/8
inch in thickness, solid or honeycomb core steel door not less than 1
3/8 inches thick, or 20 minute fire rated door.

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