Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 42·3.13
Flue discharge clearances for readily ignitable roofs
Where a flue discharges onto or near a roof with readily ignitable surfaces like thatch or shingles, increased clearances must be maintained as specified in Diagram 3.2.
Where a flue discharges onto, or in close proximity to, a roof with a surface that is readily ignitable, such as thatch or shingles, the clearances to the flue outlet should be increased to that shown in Diagram 3.2.
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