8
Clearances to Combustibles
Clearances to Combustibles
The distance to be maintained from the surfaces of the
fireplace to combustibles must be observed. Below is a list of
the most common combustible materials to name a few:
Drywall
Wood flooring
Plywood
Sub-flooring
Wood Framing
Particle board
Mill board
Plywood paneling
Maintain the following clearances:
•
Unit front, sides, rear: 2” (51 mm)
•
Combustible Floor: 8” (203 mm)
•
Combustible Sheathing above opening top: 18” (457 mm)
•
Sheathing or trim to opening sides: 8” (203 mm)
•
Mantel above opening: (refer to
Fig.9
)
•
Opening to sidewall: 24” (609 mm)
•
Hearth extension beyond front: 20” (508 mm)
•
Hearth extension beyond sides: 12” (305 mm)
•
Insulation from firebox: 2” (51 mm)
16"
10"
NON-COMBUSTIBLE
ONLY ZONE
18"
20"
22"
1 1/2"
3"
6"
8"
10"
SAFE ZONE FOR
PROJECTION OF
COMBUSTIBLE
MATERIAL
TOP OF FIREPLACE OPENING
MANTEL
LINTEL
FRONT
FIREPLACE
DOME TOP
Figure 9
Understanding Clearance to Combustibles
There is a build-up of considerable amount of radiant heat
on the outer surfaces of the Mason-Lite Fireplace. It’s critical
that proper clearances to combustibles be maintained so that
this radiant heat is maintained to safe limits.
Combustible Floor Clearances
Combustible Floor Clearances
MFPST-43 Mason-Lite Fireplaces have been designed with
clearance to combustible floors at a minimum of 8-1/2” (eight
and one half inches) as provided by the 8” metal base and
1/2” concrete board. Cover any part of the combustible floor
system left exposed with 1” (one inch) thick ceramic fiber
insulation rated up to 2,100°F.
The Mason-Lite Steel Platform , the 1/2” concrete board
above, the 1” ceramic fiber blanket or board within the
platform (
Fig.15
) and the 2” clearance for dome front, and unit
sides provide the temperature safety margin to combustible
materials.
Mason-Lite Fireplace & Chimney System
Mason-Lite Fireplace & Chimney System
Prior to starting the installation, check with local, regional or
state codes for any restrictions or required permits regarding
your fireplace installation.
1) The Mason-Lite is designed to be installed with a listed
UL-103-16” I.D. Class A, Metal Chimney System.
2)
This Mason-Lite fireplace is intended as a supplemental
heat source only. It is not intended as a primary heat
source.
3) It is the responsibility of the contractor installer (not the
manufacturer) to ensure that adequate combustion air is
provided for proper function of this fireplace. Fireplaces
take up a large volume of replacement air from outside the
house and if the house is of airtight construction, smoke
spillage may occur if proper draft is not achieved.
4) There are many conditions beyond a manufacturer’s
control regarding improper fireplace operation. The
manufacturer cannot ensure “smoke free” operation,
nor can the manufacturer take on the responsibility for
problems with surrounding construction; chimneys that
have not been built at the right heights; system drafts
caused by faulty mechanical systems; adverse weather
conditions or any other inclement environmental situations
over which the manufacturer has no control.
5)
Inspect all fireplace & chimney components for evidence
of damage prior to starting installation. Consult your local
distributor for replacement parts if necessary.
6) Under no circumstances should you make any adjustments
or modifications to the chimney system during the
installation procedure. If you do, you are not only liable
for negating the warranty, but you could very well cause a
serious malfunction of the fireplace. You must follow your
chimney manufacturer’s instructions.
7) Caution is urged if it is decided to add insulation material
to any part of the Mason-Lite Fireplace or Chimney
system, be certain that the insulation material is kept at
least 2” (two inches) away from any part of the system.
When using insulation or vapor barrier materials, cover
with a layer of plywood, particle board or gypsum board to
maintain the specified 2” (two inch) clearance.
8)
Air spaces around firebox must remain open. DO NOT fill
these open spaces with insulation or packing material of
any kind.
Chimney System Heights
Chimney System Heights
When installed, the
maximum
overall height of the chimney
system from bottom of fireplace to the top/termination chimney
is 40 feet. The
minimum
installed height of the completed
Chimney System is 14 feet with a straight flue stack, 17 feet if
the chimney includes one or two offset sections.
