Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 25·Diagram 2.3
Permanent vent openings in a solid floor for open-flued appliances
Diagram 2.3 shows the arrangement of permanent vent openings (airbrick, duct and grille) in a solid floor for open-flued appliances, with free area requirements specified in relevant sections.
Diagram 2.3 Permanent vent openings in a solid floor
airbrick, duct and grille should have an equivalent free area at least that recommended in Sections 3, 4 or 5 as relevant
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