There are a variety of issues to consider when planning to build on a specific site. Reduced bearing capacity may require specialised foundation design at considerable expense. Vegetation, tree roots, slope and local topography may effect on site drainage with roots required to be removed and any drainage issues addressed. Changing moisture conditions in the soil cause a change in soil volume. These factors will combine to affect local soils and the building structure above. The properties of the local site soil must be tested and measured.
Inclusion of these requirements for building of residential homes has resulted in a great reduction in homes with defects such as dropped floors, cracked slabs, cracked brickwork and binding doors. Water is commonly the greatest issue when it comes to building damage. Reactive soils absorb water and change in volume. Where foundation design is not appropriate to compensate for the amount of movement expected, damage to buildings will occur. Water can also cause erosion of some soils which may result in subsidence of foundations and building damage. Where building or extensions are planned a soil test must be conducted to satisfy building regulations and ensure correct design.