Technical Booklet R Access to and Use of Buildings·Page 23·3.10
Accessible entrance doorway threshold levels
Entrance thresholds should be level, but may have upstands up to 15 mm total height if required for moisture prevention. Upstands over 5 mm must have chamfered or rounded edges, and the threshold route must not create barriers or trip hazards.
An accessible entrance doorway should have a threshold which is level. However, where required due to site location (e.g. to prevent the ingress of moisture), a threshold may contain one or more upstands, provided the cumulative height of these upstands is not more than 15 mm. An upstand more than 5 mm high should have all exposed edges chamfered or rounded. The route from the access area across the threshold should not present a barrier for wheelchair users or a trip hazard for other people.
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