Technical Booklet C Site Preparation and Resistance to Contaminants and Moisture·Page 8·28
Resistance to moisture and weather
Every wall, floor and roof must be constructed to prevent harmful effects from moisture entering the building from the ground or weather.
Every wall, floor and roof shall be constructed so as to prevent any harmful effect on the building or the health of the occupants caused by the passage of moisture to any part of the building from—
(a) the ground; and
(b) the weather.
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