SECTION IV
AFTER MARKET MOBILE HOME
INSTALLATION
NOTE: FOR MOBILE HOME INSTALLATION FOLLOW RESIDENTIAL INSTAL- LATION. SECTION II, PAGE 4.
SECTION V
PRODUCING ADEQUATE
VENTILATION
The National Fuel Gas Code, ANSI Z223.1/NFPA 54 defines a confined space as a space whose volume is less than 50 cubic feet per 1,000 BTU per hour (4.8m 3 per kw) of the aggregate input rating of all appliances installed in that space and an unconfined space as a space whose volume is not less than 50 cubic feet per 1,000 BTU per hour (4.8m 3 per kw) of the aggregate input rating of all appliances installed in that space. Rooms communicating directly with the space in which the appliances are installed, through openings not furnished with doors, are considered a part of the unconfined space.
Unusually tight construction is defined as construction where:
a)Walls and ceilings exposed to the outside atmosphere have a continuous water vapor retarder with a rating of 1 perm (6 x
b)Weather stripping has been added on openable windows and doors;
c)Caulking or sealants are applied to areas such as joints around window and door frames, between sole plates and floors, between
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