Nectre Fireplaces N550 Installation Instructions Manual page 13

Installation
Masonry Chimney & Fireplace
When a metal prefabricated chimney is used, the oven may also be
connected to a masonry chimney, provided the chimney complies with the
construction rules found in the building code enforced locally. To ensure
that a masonry chimney meets the minimum standards of the National Fire
Protection Association (NFPA) it should be inspected by a professional to
make sure there are no cracks, loose mortar or other signs of deterioration
and blockage. Also have the chimney cleaned before the oven is installed
and operated.
Figure 7
Masonry chimney requirements
Ceiling joist
Floor
protection
Concrete cap
Combustible wall
Thimble -
12" of brick
Rafter
Fireclay flue
liner with
airspace
Flashing
Eave
Clearance
18" minimum
Sheathing
Airtight
clean
door
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