Building near trees

4.2.6Excavation of foundations

Excavation of foundations shall take account of the design and be suitable to receive concrete.

Where trench bottoms become excessively dried or softened due to rain or ground water, the excavation should be re-bottomed prior to concreting.

Foundation depths should be measured on the centre line of the excavation and from ground level determined from Clause 4.2.9.

Some root activity may be expected below the depths determined in accordance with this guidance. However, if significant quantities of roots are unexpectedly encountered in the base of the trench, an engineer should be consulted to determine if the excavation should be deepened.