Osburn Matrix Installation and Operation Manual
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7.4
REDUCING WALL AND CEILING CLEARANCES SAFELY
You may decrease the minimum
clearances to heat-sensitive materials
by installing heat radiation shields
between the walls or the ceiling and
the wood fire. These heat radiation
shields must be installed permanently,
and must be made of a heat-resistant
or heat-tolerant material.
An air gap must separate the heat
shield from any heat-sensitive surface.
Furthermore, the heat shield shall
extend in all directions beyond the
boundaries of the appliance surface by
a distance of not less than 450 mm.
Exceptions may apply. Refer to AS/NZS
2918:2001.
Following the installation of such heat radiation shields, the minimum clearances to heat-sensitive
materials may be reduced by applying the clearances factor in the table below:
CONSTRUCTIONS AND CLEARANCES FACTORS FOR APPLIANCES HEAT SHIELDS
WHICH ARE WITHIN 45
o
OF THE VERTICAL
HEAT SHIELD CONSTRUCTIONS
Minimum air gap
dimensions (mm)
Clearances factor
Single layer of continuous material
12
0.40
Single layer of continuous material
25
0.30
Two spaced layers of continuous material
12+12
0.20
NOTES:
1-
Masonry may be used as a heat shield material.
2-
Where heat shields are used to reduce appliance clearance dimensions, additional flue
shielding may also be required. Refer to AS/NZS 2918:2001.
3-
Non standard installations – Refer to AS/NZS 2918:2001 for guidance.
