Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 75·5.18
Protection of combustible materials from flue heat dissipation
Where flue gas temperature does not exceed 250°C, combustible materials in the building fabric must be protected from heat dissipation from the flue according to Table 5.3.
Where the flue gas temperature is not expected to exceed 250ºC the combustible materials in the building fabric should be protected from the heat dissipation from a flue in accordance with the provisions of Table 5.3.
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