Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 51·3.30
Fireplace recesses and prefabricated appliance chambers
Fireplaces must be designed to protect building fabric from fire using either a masonry/concrete recess or a prefabricated factory-made appliance chamber with specified insulation properties and minimum component thicknesses.
Fireplaces should be designed and constructed so that they adequately protect the building fabric from catching fire. They should be built utilising –
(a) a fireplace recess of masonry or concrete as shown in Diagram 3.11; or
(b) a prefabricated factory-made appliance chamber using components that are made of insulating concrete having a density of greater than 1200 kg/m³ but less than 1700 kg/m³ and a minimum thickness as shown in Table 3.5. Components should be supplied as a set for assembly and jointing in accordance with the manufacturer's instructions.
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