Technical Booklet R Access to and Use of Buildings·Page 18·2.11
Paving unit joint specifications
Where paving units are used, recessed filled joints must be no more than 10 mm wide and 5 mm deep, while unfilled joints must be no more than 5 mm wide.
Where paving units are used as surfacing material and have –
(a) recessed filled joints, the joints should be not more than 10 mm wide and 5 mm deep; and
(b) unfilled joints, the joints should be not more than 5 mm wide.
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