Strip and trench fill foundations

4.3.8Sloping ground and stepped foundations

Strip and trench fill foundations shall be taken to a suitable bearing level when building on sloping ground, and steps shall be suitably formed.

Sloping ground may require stepped foundations. Where foundations are stepped, the height of the step should not exceed the thickness of the foundation, unless it forms part of a foundation designed by an engineer in accordance with Technical Requirement R5.

Table 3: Foundation overlap

Strip foundationsTrench fill foundations
The overlap should be not less than:■ 2 x S, or
■ T (maximum 500mm), ■ or 300mm, whichever is largest.
■ 2 x S, or
■ One metre, whichever is largest.