6
AIR FOR COMBUSTION AND VENTILATION
WARNING: This fireplace should notbe installed in a confinedspace or unusually tight construction unless
provisions are provided for adequate combustion and ventilation air. Read the following instructions to insure
proper fresh air for this and other fuel-burning appliances in your home.
PRODUCING ADEQUATE VENTILATION
This fireplace shall not be installed ina room or space unless the required volume of indoor combustion air is
provided by the method described in the NATIONAL FUEL GAS CODE, ANSI Z223.1/NFPA 54, the
INTERNATIONAL FUEL GAS CODE, or applicable local codes.
The following are excerpts from National Fuel Gas Code, NFPA 54/ANSI Z223.1, Section 5.3, Air for Combustion and
Ventilation. All spaces in homes fall into one of the three following ventilation classifications:
1. Unusually Tight Construction
2. Unconfined Space
3. Confined Space
The information on pages 6 through 8 will help you classify your space and provide adequate ventilation.
Confined and Unconfined Space
The National Fuel Gas Code,ANSI Z223.1 definesaconfined space as aspace whose volume is less than 50 cu. ft. per
1,000 BTU/hr(4.8 m^3per kw) of the aggregate input rating ofall appliances installed inthat spaceand anunconfining
space as aspace whose volume is not less than 50 cu. ft. per 1,000 BTU/hr (4.8 m^3per 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.
This fireplace shall not be installed in aconfined space or unusually tight construction unless provisions are provided
for adequatecombustion and ventilation air.
·Adjoining rooms are connecting only if there are doorless passageways or ventilation grills between them
UnusuallyTight Construction
The air that leaks arounddoors and windows may provide enough fresh air for combustion and ventilation. However,
in buildings of unusually tight construction, you must provide additional fresh air.
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 one
perm (6x10
-11
kg per pa-sec-m
2
) or less with openings gasketed or sealed and
b) weather stripping has been added on windows that can be opened and on doors and
c) caulking or sealants are applied to areas such as joints around window and door frames, between sole platesand
floors, between wall-ceiling joints, between wall panels, at penetrations for plumbing, electrical, and gas lines, and at
other openings.
If your homemeets all of the threecriteria above, youmust provideadditional fresh air. See “Ventilation Air from
Outdoors”(page 8). If your home doesnot meet all of the three criteria above, proceedto “Determining Fresh-Air Flow
for Fireplace Location”.
DETERMINING FRESH-AIR FLOWFOR FIREPLACE LOCATION
Determining ifYou Have aConfined or Unconfined Space
Use this worksheet to determine if you havea confined or unconfined space.
Space: Includes the room in which you will install fireplace plus any adjoining rooms with doorless passagewaysor
ventilation grills between the rooms.
1. Determine the volume of the space Length ×Width ×Height= cu. ft. (volume of space) Example: Space size 20 ft.
(length) ×16ft. (width) ×8 ft. (ceiling height) = 2560 cu. ft. (volume of space)
If additional ventilation toadjoining room is supplied with grills or openings, add the volume of these rooms to the
total volume of the space.
