Chimney Flue Dimensions

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Chimney flue dimensions.

But chimney experts and draft measurements show that in a rectangular flue not all of the cross sectional area is equally effective in developing draft. Thickness of a lined chimney to be used as a structural component is 10 in. Chimney vent capacity chart btu h and kw pdf. For example you could vent a 6 inch stove into an insulated chimney that is 8 inches in diameter.

In most cases a step up is also fine. The rule of thumb for sizing a chimney liner is that you never want it to be smaller than the appliance exhaust hole and you don t want the liner to be three times the area of the exhaust hole of the appliance. Dimensions for square rectangular and round clay flue liner. Check with your local code enforcement officer or fire dept for proper installation.

The outer wall of your pipe also needs to be covered by your cap but it doesn t matter if your cap extends beyond the edges of your pipe. An unlined chimney s minimum wall thickness is 14 in. The ideal flue size is typically determined by the exhaust outlet of the stove or appliance. Socket type joints and self aligning joints are available in round flue liners.

The diameter of the chimney cap you choose needs to be the same as your pipe s inner diameter. 100 mm bearing length brick. Terra cotta flue intent is to contain the combustion products and direct them to the outside atmosphere. A q v 3 where.

They help protect the chimney walls from heat and minimize condensation. A cross sectional area of chimney m 2 q volume of flue gases at chimney temperature m 3 s v velocity m s in general 1 kw boiler heat requires 1100 mm 2 of chimney area. 250 mm consisting of. Quality chimney liner material that meets astm and excels in freeze thaw environments.

350 mm consisting of the same elements. For example an 8 x 8 square nominal clay chimney flue tile liner has inside dimensions of 6 3 4 x 6 3 4. Chimney vent capacity chart btu h and kw. A 6 inch stove requires a 6 inch flue.

Just muliplying these dimensions together 6 75 x 6 75 45 56 sq in. 100 mm chimney wall brick 2 2 in. Typical standards require a cross section area of the fireplace flue or chimney vent to be equal to 1 10 of the area of the fireplace opening itself for a conventional wood burning installation and without considering the effects of a glass fire door. A pipe with a seven inch inner diameter for example requires a seven inch chimney cap.

Required chimney area can be calculated as.