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F. CONNECTION TO A METAL PREFABRICATED CHIMNEY.
When a metal prefabricated chimney is used, the manufacturer's installation instructions must be followed precisely. You
must also purchase (from the same manufacturer) and install the ceiling support package or wall pass through and "T"-section
package, firestops (when needed), insulation shield, roof flashing, chimney cap, etc. Maintain the proper clearance to the
structure as recommended by the manufacturer. This clearance is usually a minimum of 2", although it may vary by
manufacturer or for certain components.
There are two methods of metal chimney installation. One method is to install the chimney inside the residence through the
ceiling and the roof. [See Figures 17:1 and 17:2,] The other method is to install an exterior chimney that runs up the outside of
the residence. [[See Figures 18:1 and 18:2.] The components illustrated may not look exactly like the system you purchase, but
they demonstrate the basic components you will need for a proper and safe installation.
The chimney must be the required height above the roof or other obstruction for safety and for proper draft operation. The
requirement is that the chimney must be at least 3' higher than the highest point where it passes through the roof and at
least 2' higher than the highest part of the roof or structure that is within 10' of the chimney, measured horizontally. [See
Figure 12:2, Page 12]
Remember: Follow the manufacturer's installation instructions and maintain the manufacturer's specified
clearance distances.
