Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 26·2.21
Construction of masonry chimneys
New masonry chimneys must be constructed with a flue liner and masonry suitable for the intended application. Clay, concrete, or equivalent liners meeting specific BS EN standards are acceptable for solid fuel and other fuel types.
A new chimney should be constructed with a flue liner and masonry suitable for the intended application. The following liners are suitable for a solid fuel appliance as well as being generally suitable for other fuels –
(a) a liner with a performance that is equal to that corresponding to the designation T400 N2 D 3 G, as described in BS EN 1443, such as –
(i) clay flue liners, with rebates or sockets for jointing, meeting the requirements for Class A1 N1 or Class A1 N2 as described in BS EN 1457;
(ii) concrete flue liners meeting the requirements for the classification Type A1, A2, B1 or B2 as described in BS EN 1857; or
(iii) other products that meet the designation above.
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