The 2012 International Residential Code (R302.12) requires a draft stop in combustible construction when there is a concealed space between floors. This condition is often found in homes that utilize a floor/ceiling girder truss system in lieu of solid lumber joists. The draft stop must be installed as to equally divide the concealed space as much as possible. Draftstopping materials may include; a minimum of half inch gypsum, three-eighth inch wood structural panels, or any other materials approved by the local jurisdiction.
The difference between draftstopping and fireblocking can be found in the definitions, and in section R302.11 Fireblocking. While draftstopping is intended to restrict the movement of air in a concealed location, fireblocking is intended to resist the passage of flame in both vertical and horizontal assemblies.
6,948 total views, 6 views today