Technical Booklet R Access to and Use of Buildings·Page 18·2.10
Surface finish tolerances for formless and paving materials
Formless surfacing materials must have undulations not exceeding 3 mm under a 1000 mm straight edge. Paving units must have level differences at joints not exceeding 5 mm.
Notwithstanding the provisions of paragraph 2.9(d) –
(a) where formless materials are used as surfacing, any undulations should be not more than 3 mm measured from a point below a 1000 mm straight edge; and
(b) where paving units are used as surfacing material, any difference in level between the units at the joints, should be not more than 5 mm.
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