The structure is by far the most important part of a building survey. In many instances, structural problems can be very expensive to repair. The structural part of the building survey involves examining all the visible parts of the exterior, the roof, interior walls, ceilings, floors, attic spaces, doors and window frames. Particular attention is paid to visible evidence of past or present movement such as cracks, settlement, bowing, lifting and heaving.
Movement or structural settlement can occur at any time. Regular monitoring of the property should be undertaken.
Foundations are the most important structural element of a property. Older properties would normally have stone foundations. Common types of foundations are now of poured concrete and are generally termed strip foundation, raft foundations and pier and beam foundations. As foundations are not visible during a building survey the building surveyor will be looking for visible evidence of settlement / movement in the walls, floors, arches, etc to determine the likelihood of foundation movement. Most older properties may have settled to some extent. The main concern here would be recent or ongoing settlement or movement.
Walls are divided into structural walls and non-structural / partition walls. Outer walls are almost always structural bearing walls while inner walls maybe either structural or non-load bearing partition walls. Alterations to walls should not be carried out until such time as it has been confirmed that the wall to be altered in not load-bearing.
Floors should be designed to take the dead and imposed loads imposed on them. The scope of a pre-purchase building survey does not carry out calculations to confirm the structural effectiveness of the floor, but whether the floor appears to be in a structurally sound condition.
Adequate ventilation is required under suspended timber floors to remove excessive moisture. Excessive moisture in the crawl space under the timber floor is a common reason for decay in floor joists and floorboards.
Previous damage caused by flooding would normally have been repaired and flooding damage may not be obvious to a building surveyor at a time of a building survey. It is important to check with people living in the immediate area, the local authority and insurance companies who insure properties before purchasing a home.