Traditionally the foundations for the walls of houses and similar buildings have consisted of strip foundations (generally unreinforced) with block or brick masonry up to damp proof course level. In ‘trench-fill’ narrow trenches are dug to the required foundation depth and completely filled with concrete.

This approach minimises the amount of excavation as access to lay blocks or bricks in the trench is no longer required. In addition, the trench is only open for a short time, leading to safer site working.