Technical Booklet E Fire Safety·Page 87·3.14
Rooflights – Material classification and size limits
Rooflights in non-protected stairways may use lower surface classifications if they meet specific material requirements and size restrictions as detailed in Table 3.2.
Other than in a protected stairway a rooflight may be of a classification lower than the relevant Class given in Table 3.1 provided that –
(a) where it is –
(i) a plastic material which has a lower surface with a classification not lower than Class 3; or
(ii) a thermoplastic material which has a lower surface with a classification not lower than Class 3 or is classified as a TP(a) rigid or TP(b) product,
the size of the rooflight does not exceed the relevant maximum area given in Table 3.2; and
(b) where there is more than one rooflight in the ceiling of a room or space –
(i) the area of rooflights does not exceed the relevant maximum total area given in Table 3.2; and
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