Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 40·3.9
Height of flues
Flues must be high enough to ensure sufficient draught to clear combustion products. A flue is satisfactory if it is at least 4.5 m in height and follows paragraphs 3.11 to 3.13, or if designed using the calculation procedure in BS EN 13384: 1.
A flue should be high enough to ensure a sufficient draught to clear the products of combustion. The height necessary for this depends upon the type of appliance, the height of the building, the type of flue and the number of bends in it, and a careful assessment of local wind patterns. A flue should be satisfactory if –
(a) it is at least 4.5 m in height and the provisions of paragraphs 3.11 to 3.13 are adopted; or
(b) the calculation procedure within BS EN 13384: 1 is used as the basis for deciding whether a flue design should provide sufficient draught.
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