Technical Booklet B Materials and Workmanship·Page 15·2.13
Resistance to moisture
Materials likely to be adversely affected by moisture from ground, weather or condensation are suitable if the construction resists moisture passage or the material is treated or protected from moisture.
Any material which is likely to be adversely affected by moisture from the ground, weather or condensation will be suitable if –
(a) the construction will resist the passage of moisture to the material; or
(b) the material is treated or otherwise protected from moisture.
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