Most of the houses I worked on years were strip foundations with 9 inches of concrete. After that hot summer of 76, and the following claims, the depth of foundations was increased by the NHBC, so trench fill became more popular. This had more to do with the practical point of building in a deep trench, and the economic side of materials v labour costs.
Some houses were built off different founds such as a raft or piles, but strip founds are normally the most cost effective when ground conditions allow them.
Some houses were built off different founds such as a raft or piles, but strip founds are normally the most cost effective when ground conditions allow them.