NFPA Requirements
Termination (Height)
4.2 Termination (Height)
Chimneys and vents shall terminate above the roof level in accordance with the following requirements.
4.2.1 Masonry chimneys shall extend above the highest point at which they pass through the roof of a building by at least the distance specified below.
Hearth Extensions
11.3 Hearth Extensions
Masonry fireplaces shall have hearth extensions of brick, concrete, stone, tile, or other approved noncombustible material. (see drawing below)
11.3.2 Fireplace opening less than 6 ft square (LxW=less than 6) A=16" B=8"
11.3.3 Fireplace opening greater than 6 ft square (LxW=greater than 6) A=20" B=12"
Clearance
11.2.3 Clearance to Combustibles
11.2.3.3 Woodwork, such as wood trim, mantels, and other combustible material shall not be placed within 6" of fireplace opening (Distance "C" see drawing below)
11.2.3.4 Combustible material above and projecting more than 1.5" shall not be placed less than 12" from fireplace opening (Distance "C" see drawing below)
Masonry Fireplaces (Smoke Chamber)
11.2 Masonry Fireplaces
11.2.1.10 The smoke chamber height shall not be greater than the inside width of the fireplace room opening
11.2.1.11 The smoke chamber depth shall not be greater than the depth of the fireplace firebox
11.2.1.12 The inner surfaces of the smoke chamber shall be smooth (parged) and not inclined more than 45 degrees from vertical
