Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 47·3.23
Hearth for Independently Certified Low-Temperature Appliances
Appliances not in recesses that are independently certified to not exceed 100°C may stand on a non-combustible board, sheet material or tiles at least 12 mm thick. All other appliances must use a constructional hearth.
Where an appliance is not to be located in an appliance recess and it has been independently certified that it cannot cause the temperature of the hearth to exceed 100ºC, it should stand wholly on a hearth made of non-combustible board, sheet material or tiles not less than 12 mm thick. See Diagram 3.10(a). All other appliances should be placed on a constructional hearth in accordance with paragraphs 3.24 to 3.29. See Diagram 3.10(b) and (c).
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