Structural movement: when is it a problem for your home?

House walls are supported by the foundations and any movement below ground may lead to cracks appearing in the walls or you may spot differences in ground levels in different parts of your house.

Small amounts of movement are common during the lifespan of your house as it settles. This may lead to minor cracks, but severe wall cracking may be a sign of a more serious issue. It is vital that you get a building surveyor to check this over for you, as structural movement could involve very costly remedial works.

House foundations can fail and give rise to problems for a number of different reasons. Examples include having a weak concrete mix, where the wrong mix ratio of sand, cement and aggregate has been used, or insufficient size for their width and depth or the wrong type of foundations for the type and size of property, including certain types of ground conditions that require a specific type of foundation. Other contributing factors are when foundations are affected by settlement (movement normally caused by the initial weight of the building pressing down on the foundations) or subsidence (movement in the foundations mainly due to changes in the ground conditions).

Differential or uniform settlement?

There are two sorts of settlement - differential or uniform. Differential occurs at differing rates between different portions of a building. It can also occur if there is difference in soils, loads, or structural systems between parts of a building. This can lead to the building visibly distorting so you can see that the floors slope, windows may not work properly and walls and window glass may crack.

With uniform settlement, as it sounds, settlement occurs at the same rate throughout all parts of a building. If all parts of a building rest on the same kind of soil, then uniform settlement is the most probable type to take place.

Finding the root of structural problems

Another cause of foundation damage and movement may be due to trees, which can cause problems underground. This can be either be due to clay shrinkage, as tree roots drain water from the ground, or where foundations are lifted by ground heave, as a result of clay swell, where trees have been removed. Big trees can also cause a great deal of damage with their roots, which can disturb drains, and push against foundations and walls. This is a gradual process and, like other damage, may only be noticeable after a considerable length of time.

Get in touch with our professional Building Surveying team if you think you have problems with the foundations at your home or commercial premises. Our team are members of the Royal Institution of Chartered Surveyors (RICS). Our membership assures you that we have the expertise and qualifications required to provide you with a detailed and accurate ‘health check’ on the condition of a property.  You can find more details of the services we provide for home buyers, including a Level 3 Home Survey, here.