Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 26·2.18, 2.19
Provision of flues
Combustion appliances (except flueless types) must have a suitable flue connected to discharge outside air. Single-appliance flues are covered here; multi-appliance flues must follow BS 5410 or BS 5440 depending on fuel type, and each solid fuel appliance needs its own flue.
This Technical Booklet provides guidance on how to construct a flue or chimney that serves only one appliance. A flue designed to serve more than one appliance should follow the recommendations of BS 5410: Part 1 for oil and BS 5440: Part 1 for gas-fired combustion appliances. Each solid fuel appliance should have its own flue.
A combustion appliance, other than a flueless appliance, should incorporate or be connected to a suitable flue that discharges to the outside air.
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