Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 47·3.22
Hearth Construction Requirements
Hearths must be constructed from robust materials and appropriate dimensions to prevent combustion appliances from igniting building fabric and furnishings. If the chimney is not independently supported, the hearth must support the weight of the appliance and chimney.
A hearth should be constructed of suitably robust materials and to appropriate dimensions so that, in normal use, it prevents the combustion appliance setting fire to the building fabric and furnishings. If the chimney is not independently supported, the hearth should be able to accommodate the weight of the combustion appliance and its chimney.
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