Subsidence or foundation movement, particularly in older buildings, is primarily caused by two types of event or change in circumstances – escape of water and variations in groundwater levels.
Escape of water, through leaking drains or leaking water supply pipes, is the most common cause of foundation movement. Services which are leaking over long periods gradually reduce the load bearing capacity of the soils by removal of the finer particles in granular or cohesionless soils or having a ‘softening’ effect in fine or cohesive soils.
After careful examination of the evidence above ground, any investigation into alleged subsidence will require information from below ground. This will help determine the cause and aid in determining the most appropriate repair solution.
So if the drainage is within the vicinity of any area of the building under distress, a drain test is highly recommended. Furthermore, we always recommend testing of all other water services such as the water supply into the house and the hot and cold supply.
Substruck Ltd. has the knowledge and expertise to complete all of these tests which will offer part of the investigation process into subsidence. Drain testing, known as hydrostatic drain testing is complemented by CCTV inspection and surveying.
If you think that you have cracking that is new or progressive, please contact us and we can arrange to inspect the property and prescribe the best course of action.