9.21.5. Clearance from Combustible Construction

9.21.5. Clearance from Combustible Construction
9.21.5.1. Clearance from Combustible Materials
  1. The clearance between masonry or concrete chimneys and combustible framing shall be not less than
    1. 50 mm for interior chimneys, and
    2. 12 mm for exterior chimneys. (See Note A-9.21.5.1.(1).)
  2. A clearance of not less than 150 mm shall be provided between a cleanout opening and combustible material.
  3. Combustible flooring and subflooring shall have not less than a 12 mm clearance from masonry or concrete chimneys.
9.21.5.2. Sealing of Spaces
  1. All spaces between masonry or concrete chimneys and combustible framing shall be sealed top or bottom with noncombustible material.
9.21.5.3. Support of Joists or Beams
  1. Joists or beams may be supported on masonry walls which enclose chimney flues provided the combustible members are separated from the flue by not less than 290 mm of solid masonry.