Technical Booklet E Fire Safety·Page 124·Table 4.8
Maximum nominal internal diameter of pipes passing through fire separating elements
Table 4.8 specifies the maximum internal diameters permitted for pipes of various materials when they pass through fire separating elements, depending on whether the element encloses a protected shaft, separates dwellinghouses or compartment walls between flats, or is in any other situation.
Table 4.8 Maximum nominal internal diameter of pipes passing through fire separating elements
Pipe material and maximum nominal internal diameter (mm)
Situation: Non-combustible material(1) | Lead, aluminium, aluminium alloy, uPVC(2), fibre-cement | Any other material
1 Construction (but not a wall separating buildings) enclosing a protected shaft which is not a stairway or a lift shaft: 160 | 110 | 40
2 (a) A wall separating dwellinghouses (b) A compartment wall or compartment floor between flats: 160 | 160 (stack pipe)(3) 110 (branch pipe)(3) | 40
3 Any other situation: 160 | 40 | 40
Notes:
(1) A non-combustible material (such as cast iron, copper or steel) which if exposed to a temperature of 800°C, will not soften or fracture to the extent that flame or hot gas will pass through the wall of the pipe.
(2) uPVC pipes complying with either BS 4514 or BS 5255 or BS EN 1329-1.
(3) These diameters are only in relation to pipes forming part of an above-ground drainage system which is enclosed as shown in Diagram 4.11. In other cases the maximum diameters against Situation 3 apply.
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