(a) Each flue of every chimney shall be separately lined throughout with fire-clay flue lining not less than three-fourths of an inch thick, of good commercial quality. Adjoining flue linings shall have the joints broken at least seven inches. The masonry shall be built around each section of lining as it is placed, all voids shall be completely filled with mortar, and all joints shall be struck smooth on the outside. No defective flue lining shall be used. No hollow masonry units shall be used.
(b) The size of flues for fireplaces shall be approximately one-tenth the area of the fireplace masonry opening, although actual design of flue size shall depend on proven standards for the correct ratio of opening to flue size.
(c) The area or size of flue linings for heat-exhausting furnaces or stoves for either gas, oil, coal, wood or coke burning units shall depend upon the requirements of manufacturers' literature for the appliance and/or the specifications from a mechanical engineer. Such flues shall be made of fireclay or approved equivalent, not less than one inch thick, with joints properly designed to effect a permanent seal and with eight inches of solid clay brick surrounding masonry walls.
(d) Flues for low-temperature (less than 120 degrees Fahrenheit) venting or high- efficiency furnaces may use schedule 40 rigid polyvinylchloride (PVC) plastic pipe for combustion air intake and flue exhaust, sizes to be in accordance with the manufacturer's sizing criteria for the capacity of the furnace installed. Flue and intake piping may be extended to the outside through side walls or the roof at the rear of the slope.
(Ord. 1992-101. Passed 1-14-92.)
(e) Except as provided in Section 1385.08(b), metal vent flues, either single or double- walled insulated pipes, for heat-exhausting appliance pipes, are not permitted.
(Ord. 1999-129. Passed 7-6-99.)
(f) Smoke pipe inlets to flues shall be only through the side of the chimney and shall consist of fireclay or metal thimbles securely set in the chimney wall with mortar. Such openings shall be at least eighteen inches below any exposed wood or wood lath and plaster ceilings, but if such combustible material is protected with an incombustible shield at least three inches below the joists or the ceiling and extending at least twelve inches in all directions beyond the area occupied by the smoke pipe, then such openings may be not less than ten inches below such shield. Neither the intake pipe nor the thimble shall project into the flue.
(g) All flues shall be thoroughly cleaned and left smooth on the inside.
(Ord. 1992-101. Passed 1-14-92.)