Technical Booklet B Materials and Workmanship·Page 8·0.2
Suitability of materials - Nature and quality
External wall and roof materials must provide effective weather resistance without relying solely on paint or coatings, and materials requiring maintenance must be readily accessible.
To be of a suitable nature and quality, materials –
(a) for use as the weather resisting part of an external wall or roof should not rely on being painted, or coated, surfaced or rendered with any other material which when used, does not in itself constitute effective resistance against weather; or
(b) which depend on periodic maintenance, replacement or renewal should be readily accessible or positioned so that such maintenance, replacement or renewal is practicable.
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