JKJeremy
Member
I need to install a type 1 hood in a project. it is located on the rear wall of the structure mounted to the ceiling joists and rear wall. i see section 507.9 of the mechanical code that has an exception for clearances provided that the hood is mounted to sheet metal on gypsum on NONCOMBUSTIBLE structure that extends 18 inches in all directions from the hood. We have changed the wall studs to metal to accomodate this requirement and extended the height of the walls so that the wood ceiling joists are 18" above the top of the hood. However today the hood manufacturer informs me that they can manufacture a hood that is labeled as a zero clearance to combustibles. that being the case can i go back to using wood studs and drop my roof bearing back down 18". we would still place 5/8" type x gyp. on the walls and bottom of joists with a sheet metal panel on the walls extending beyond the hood 18" on the sides. any help at all would be appreciated as we would really like to use wood framing everywhere.