Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 62·Diagram 4.4
Location of flue outlets near roof windows or openings
Flue outlets serving gas appliances must maintain a minimum clearance of 600 mm horizontally and 2000 mm vertically from roof windows or openings; the flue should not penetrate the shaded area shown in the diagram, and this applies to both pitched and flat roofs.
Location of outlets near roof windows or openings (from flues serving gas appliances). The flue should not penetrate the shaded area. Minimum clearance: 600 mm horizontally, 600 mm vertically from roof window or opening, with 2000 mm vertical measurement shown. Note: applicable to both pitched and flat roofs. This diagram must be read in conjunction with Diagram 4.3 and Table 4.3.
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