Chelmer offers a complete ‘one-stop’ shop all domestic and commercial subsidence investigations.
Working with leading Loss Adjusters, Insurers and Engineers, Chelmer has developed a scope of subsidence investigations and is proud to offer and deliver this high service to clients.
Chelmer understands how important it is to ensure as much relevant information is obtained believe the unique ’one-stop’ service offered makes the whole claims process easier for and ultimately the Policyholders.
All Chelmer Site Operatives are well presented in company uniform, fully trained (including scanning and confined spaces entry) and are sympathetic to the often sensitive nature subsidence claims. At Chelmer we understand that the process can be traumatic for the and we do our utmost to ensure this element of the claim is hassle-free and as smoothly as possible.
Chelmer offer a comprehensive service and issue a single easy to read report incorporating aspects of the investigation.
Subsidence Services Provided by Chelmer
Trial Pits and Boreholes
- Hand excavated trial pits to expose and inspect footing detail/construction.
- Detailed sections and photographs of trial pits are incorporated in the final report.
- Extended trial pits can also be carried out to expose and inspect underpins, beams, pads and also pile caps.
- Opening up works and specialist reinstatement are also available as necessary, and these works are undertaken to the highest standards by our Build department.
- Borehole depths for subsidence investigations usually range from 3m to 6m. These are normally carried out using traditional hand auguring techniques.
- Where hand drilling method proves difficult (e.g. in gravels) Chelmer offer clients the flexibility of completing the borehole using a second man machine rig (all Chelmer subsidence investigation units carry a chanical auger to be used as necessary). This ensures required borehole depths are achieved and this service sets Chelmer apart from our rivals.
- In situ testing is also carried out and depending on ground conditions this will either be a Shear Vane or Mackintosh Probe, sometimes even both.
Soil Testing
- Soil samples are retrieved during the investigation process and tested according to instructions by our Laboratory.
- Testing is scheduled and undertaken swiftly to ensure reporting times are met. By having the in-house Laboratory, Chelmer are able to prioritise any urgent jobs for clients.
- A full suite of testing is available, from Atterbergs, Moisture Contents, Soil Suctions, Organic content, Particle Size Distribution and Sieve Analysis.
Root Identification
- On site vegetation is identified and marked clearly on the site plan.
- When root activity is found in the subsoil, root samples are extracted and sent for species identification as requested by the client. These results are often critical in identifying offending trees in subsidence cases where damage is caused by root induced desiccation of the clay subsoil.
Drainage
- Defective drains can be a cause of subsidence but can also be damaged by ground movement.
- Chelmer undertake full CCTV surveying using the latest Wincan technology.
- Hydraulic testing to establish if a section of drainage is leaking is also carried out when instructed.
- Chelmer also undertake specialist drainage investigations, e.g. tracing and surveying of ‘blind’ drainage systems where there is no manhole access into the system. Also, investigation of ‘blind’ surface water systems and soakaway integrity checks.
- Detailed reports are incorporated into the final report and where relevant Chelmer also supply a quotation to undertake any repairs that may be recommended. This eliminates additional administration time clients spend requesting and chasing quotes for any repairs.
- Chelmer are also able to undertake local drainage repair works at the time of the Site Investigation.
- Leak detection of water supply pipes and other pipework is a specialist service that Chelmer also offer, and this can be undertaken at the same time as the main investigation works.
Interpretative Reports
- The Consultancy department are able to provide interpretative reports for subsidence related site investigations, from Heave Analysis to Ground Movement Analysis.
- Site Investigation results are analysed and a detailed interpretative report compiled, outlining the findings and including and interpretation of the data. Remedial measures and recommendations are also discussed.
Movement Monitoring
- Crack Monitoring – Chelmer are able to carry out crack monitoring installations using demec monitoring studs at the time of the Site Investigation. Readings are taken at specified intervals thereafter using digital callipers. Avonguard tell-tales can also be used if the client specifies.
- Level Monitoring – This is a very useful method to establish the pattern and scope of movement to a structure. Usually a reference (datum) point is required and as such a deep datum is installed at the time of the main site investigation. Level monitoring stations are then installed on the relevant elevations and readings taken at specified intervals. All level monitoring works are undertaken to comply with BRE Digest 386.(Monitoring building and ground movement by precise levelling).
- Verticality Surveys – Also known as ‘Plumb’ surveys, these verticality surveys are useful in establishing the lateral movement of a structure. This type of survey can be a one off or ongoing readings can be taken to monitor any deviation over a specified period.
- Floor Distortion Surveys – Using laser levels Chelmer also offer this service where the distortion in the floor of a building can be measured. The results are supplied on a plan of the area surveyed and this is a useful exercise in understanding the overall level of subsidence related movement in a building.
