Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 47·3.24
Constructional Hearth Dimensions and Materials
Constructional hearths must have plan dimensions as shown in referenced diagrams and be made of solid non-combustible material such as concrete or masonry, at least 125 mm thick including any non-combustible floor and decorative surface.
A constructional hearth should – (a) have plan dimensions not less than those shown in Diagram 3.7; and (b) be made of solid, non-combustible material, such as concrete or masonry, not less than 125 mm thick, including the thickness of any non-combustible floor and/or decorative surface.
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