Technical Booklet E Fire Safety·Page 107·4.22
Openings in compartment walls which separate buildings or occupancies
Compartment walls separating different buildings or occupancies must have no openings except for means of escape (with fire-resisting self-closing doors matching the wall's fire resistance) and pipes (which must comply with specific piping regulations).
A compartment wall which is common to two or more buildings, or which separates different occupancies in the same building, should have no openings other than those for –
(a) means of escape in case of fire – when a fire-resisting self-closing door (see paragraphs 4.29 to 4.35) having the same period of fire resistance as that of the compartment wall should be provided; and
(b) the passage of a pipe – when the opening in the wall should comply with paragraphs 4.43 and 4.45 to 4.47.
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