Southwick Primary Extension


Working with Hodges Associates, we were asked to engineer a single storey extension to create additional teaching space.

The location was restricted and involved use of new and existing foundations, with some overbuild to existing roof structures.

One of the key structural issues given the shrinkable nature of the clay subsoil, and the proximity of a row of trees, was building subsidence and heave risk.  It is important to test the clays to determine shrinkage potential, and to design both for future tree growth, and the possibility that loss of the trees would result in ground recovery.

Put simply, clay formations  can go up or down and foundation design has to protect against both eventualities.  In this case depth was increased to get below the influence of trees roots, and anti-heave material was provided to the sides of the trench fill foundations.  A methodology was developed to facilitate positioning of the materials without the need to enter the deep excavations.


Architecture: Hodges Associates