Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 42·3.13
Risk of spontaneous combustion in thatched roofs
Thatched roofs can be vulnerable to spontaneous combustion from heat transferred through flues; rigid twin-walled insulated metal flue liners in ventilated masonry chimneys are recommended to reduce this risk.
It should be noted that thatched roofs can sometimes be vulnerable to spontaneous combustion caused by heat transferred from flues building up in thick layers of thatch in contact with the chimney. To reduce this risk it is recommended that rigid twin-walled insulated metal flue liners be used within a ventilated (top and bottom) masonry chimney void provided they are adequately supported and not in direct contact with the masonry.
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