Foundations

The purpose of foundations is to provide a level and stabel base on which to build. Foundations should generally be twice as wide as the wall that is to be built on them. The depth of the foundations varies but for most pond work 250mm is deep enough; however if the base material is unstable, or liable to crack and heave such as clay, it is wise to err on the side of caution and dig down to 500mm. Fill the majority of the void with hardcore and compact it by beating it down with a heavy hammer or by using a vibrating compaction machine before filling up to the required depth with concrete.