Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 43·3.14
Location and shielding of flue pipes - basic requirements
Flue pipes must only connect appliances to flues and cannot pass through roof spaces, partitions, walls or floors except directly into a flue. They must be guarded if at risk of damage or if burn hazards are not immediately apparent.
A flue pipe should only be used to connect an appliance to its flue. It should not pass through any roof space, partition, internal wall or floor, except to pass directly into a flue through either a wall of the chimney or a floor supporting the chimney. A flue pipe should also be guarded if it could be at risk of damage or if the burn hazard it presents to people is not immediately apparent.
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