Our engineers set up all crack monitoring, using Demec studs and digital callipers during our initial visit with the Policyholder. We measure movement to the principal cracks, recording the downward rotational movement to the superstructure. This enables us to record a datum set of readings, against which we can then compare any further trends of movement.
Our Field Technicians revisit every two months to record further readings which reveal the trend of movement and the impact of any mitigating action taken.
We are familiar with the emotional trauma that is associated with Subsidence. Our specialists prepare a detailed photographic record of all damage and defects seen at the property, which enables them to provide a detailed Engineer’s Report to the Policyholder which fully explains the factual damage seen and the most likely causation.
Upon receipt of the site investigation and laboratory analysis, our Subsidence Specialist will have a clear picture of the cause of the subsidence movement and can provide targeted recommendations for appropriate mitigating measures.
When we need to implement any sub-structure schemes or other technical interventions, these are referred for review and approval by our Senior Engineers. This ensures the appropriateness of each scheme for the individual Policyholder’s home.
Heave is the opposite to subsidence, with upward movement of structures, caused by over expansion of clay subsoils. It happens when the balance between the ground conditions and the structure is broken.
Removal of trees, which are significantly older than the newest part of the structure, allows ‘free’ water within the soil structure causing it to swell beyond its ‘normal’ condition. The precise amount of swelling of the subsoil is difficult to predict, as is the time required for the subsoil to recover to its ‘normal condition’.
The swelling of the subsoil produces powerful expansion forces which we see when they push the foundations of structures up causing crack damage.
Heave can occur when vegetation is removed and there are inadequate anti heave measures incorporated in new buildings or to remedial works to existing buildings.
Fortunately, heave is relatively rare, but requires expensive remedial schemes to rectify its effects.
Landslip occurs to sloping ground when excessive water enters a crack at the top of the slope. The water creates a slip surface allowing either bulk or circular slippage of the soil, causing damage to any structure built on the ‘slipped’ soil. This often happens after periods of very heavy rainfall which destabilises the slope. Examples include railway embankments, road embankments, coastal erosion and any sloping sites where buildings have been built on them.
Once the ‘slip’ has occurred, it is usual for the toe,(bottom), of the slope to be stabilised prior to stabilisation works to the uphill ground. Unlike Subsidence or Heave, Landslip creates a lateral force on the sloping soil and any structures built on it. Remedial works require a thorough understanding of the behaviour of the sloping ground and can be extensive and expensive.
ProSITE is our specialist Site Investigation and Monitoring Services that can be utilised by clients independently of our full subsidence claims handling service.
Level monitoring measures the trend of actual movement to the property’s foundations. It is a more specialist and more expensive exercise, so we target its use and thus our Principal’s expenditure, to those claims where we need to provide evidence to commercial third parties or to support tree preservation order applications.
We arrive at the Policyholder’s property ready to fully investigate and diagnose the cause of potential subsidence damage, having already undertaken a video triage to enable us to provide a bespoke approach to their homes. Our site investigation teams undertake targeted investigations under the on-site direction of our Subsidence Specialists.
This aligned and parallel approach, reduces the need for unnecessary visits and ensures that the right investigations are undertaken first time. Our experience shows that this reduces lifecycle, unnecessary protracted investigations and an overall reduction in indemnity spend
Once the relevant facts are known and equipped with accurate information, we scope the required repairs and utilise ProACT, our Builder Repair Network, to ensure works are undertaken in a timely manner and to a high standard.
When appropriate, and during our site investigation, soil and root samples are recovered from the investigations and submitted for analysis and identification This provides our Subsidence specialist with further information to support their initial diagnosis and the nature, and condition of the subsoil beneath the property’s foundations.
Armed with this information, targeted mitigation works can be undertaken to address the underlying cause of the subsidence movement.