Technical Booklet R Access to and Use of Buildings·Page 8·94
Sanitary conveniences in dwellings
Requires provision of a water closet and washbasin in the entrance storey of a dwelling, or in the principal storey if the entrance storey contains no habitable rooms.
In a dwelling a sanitary convenience shall be provided—
(a) in the entrance storey; or
(b) where the entrance storey contains no habitable rooms – in the principal storey.
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