BUILDING CONSTRUCTION AND OCCUPANCY TYPES - Fire …

Heavy timber structural members--columns, beams, arches, floors, and roofs--are unprotected wood with large cross-sectional areas. A minimum dimension of eight inches for structural wood supports (columns, beams, arches, and girders) is required. All other exposed wood must have a minimum dimension of two inches. Concealed spaces usually

  Members, Fire, Woods, Exposed, Exposed wood