Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 30·Diagram 2.5
Separation of Combustible Material from Factory-Made Metal Chimney
Factory-made metal chimneys passing through cupboards, storage spaces or roof spaces must maintain a minimum clearance zone around them with no combustible materials, determined by manufacturer's testing or a minimum of 25 mm, whichever is greater.
No combustible material in shaded zone. Width of shaded zone at least equal to manufacturer's declared minimum distance (XX mm) as defined by testing to BS EN 1443: 2003 or 25 mm, whichever is the greatest. Factory made metal chimney designated to BS EN 1856: 1. Non-combustible plate with spacer e.g. manufacturer's fire stop component used at floor and ceiling penetrations. Plasterboard casing and timber framing shown in section detail.
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