Precision Monitoring
Structuralmonitoring, 24/7.
Automated, sub-millimetre deformation monitoring of basements, façades, tunnels and adjacent structures across London and the South East. Live dashboards, trigger-level alerting and chartered-surveyor sign-off — built to satisfy TfL, Network Rail and London borough party-wall regimes.
Why monitoring matters in London.
Almost every basement, deep excavation or city-centre redevelopment in London now sits inside someone's zone of influence — a neighbouring listed façade, a Network Rail cutting, a Crossrail tunnel, a London Underground escalator, or a row of Grade II terraces with a worried party-wall surveyor on the case. The right monitoring scheme protects the programme as much as it protects the structure: it gives the temporary-works designer empirical evidence, lets third-party asset owners sign off ground movement, and keeps a contractor's argument out of legal proceedings.
We design risk-based monitoring schemes around predicted movement envelopes, not arbitrary tolerances. A typical London basement scheme might involve fifty monitoring prisms on adjacent buildings, ten reference prisms on stable structures, biaxial tilt sensors on the existing substructure, vibrating-wire crack meters on listed façades, and pore-pressure piezometers in the retained soil. All of it ticks on Leica GeoMoS Now!, every reading logged with a precise timestamp, every Amber breach pushed to a defined responder list within seconds.
Outside the M25 we apply the same rigour to bridge deflection, tunnel-ring convergence, slope stability and heritage-building behaviour. Whether the project is a two-storey London townhouse basement or a thirty-month strategic infrastructure scheme in Kent, the methodology is consistent — and the data is always defensible.
Our monitoring methodology.
- PHASE 01
Risk-based scheme design
We work with the temporary works designer and the geotechnical engineer to set Amber and Red trigger levels for each monitored point — typically based on a percentage of the predicted ground-movement envelope around basement boxes, secant piles or tunnel zones of influence.
- PHASE 02
Reference network & installation
Stable reference prisms are installed on independent structures well outside the zone of influence. Monitoring prisms, MEMS tilt sensors, vibrating-wire piezometers and crack meters are bonded to the structure with reflectorless verification before commissioning.
- PHASE 03
Automatic acquisition
Leica TM60 / TM50 Automatic Total Stations cycle the network on a schedule (typically hourly), feeding GeoMoS Now! cloud software. Tilt, crack and pore-pressure sensors stream over GSM gateways to the same dashboard so contractors and consultants see one unified view.
- PHASE 04
Alerting & reporting
Movements that breach Amber or Red trigger levels generate immediate SMS and email alerts to the response team. Weekly trend reports, signed by a chartered surveyor, are issued in PDF and CSV — fully traceable for project assurance and third-party stakeholders such as TfL and Network Rail.
Defensible instrumentation.
Every monitoring asset is calibrated, certificated and installed by IOSH-trained engineers. Cabinets are IP66 rated with redundant solar-charged power for sites where mains supply is unreliable.
Leica TM60 Automatic Total Station
0.5" angular accuracy, ATRplus prism recognition, sub-mm precision
Leica TM50 ATS
1" angular, used on smaller monitoring schemes and façades
Leica Nivel220 Tilt Sensor
Biaxial inclinometer, 1 µrad resolution, used on tunnel rings and piles
Geokon 4420 Vibrating-Wire Crack Meter
0.025% FS resolution, ideal for façade and party-wall cracks
Where we monitor.
Movement risk lives anywhere a structure interacts with new works. These are the scenarios we deploy on most often.
- Basement and underpinning works
- Adjacent third-party structures
- London Underground / Network Rail zones of influence
- Heritage and listed-building façades
- High-rise core verticality monitoring
- Bridge and viaduct deflection
Structural monitoring FAQs.
- What sub-millimetre accuracy can you actually achieve in the field?
- On a properly designed reference network with stable references and good prism geometry, our standard deviation per ATS cycle is typically 0.3 to 0.5 mm in 3D position. Tilt sensors operate at 1 µrad resolution; vibrating-wire crack meters resolve to better than 0.01 mm.
- Can the monitoring system tie into TfL or Network Rail third-party agreements?
- Yes. We have delivered schemes that meet TfL Asset Protection, Network Rail BAPA and Crossrail-style monitoring requirements. We can issue data via secure web dashboard with read-only stakeholder accounts, and we can integrate with existing third-party reporting templates.
- What happens if a trigger level is breached?
- The system raises immediate SMS and email alerts to a defined responder list, escalates if not acknowledged, and locks the affected data point on the dashboard pending review. A chartered surveyor reviews every Amber and Red breach within an agreed response window — often before the next site shift starts.
- Do you handle installation, commissioning and decommissioning?
- Yes. We provide the full lifecycle: scheme design, supply and installation of prisms / sensors, secure power and comms cabinets, commissioning, ongoing monitoring, weekly reporting, and final demobilisation with archived datasets handed over to the client at project close.
Related services & locations
Other services
Risk review
Need a monitoring scheme
designed to your TWS?
Send us your temporary-works statement and the predicted movement envelope — we'll come back with a fully resourced monitoring proposal and trigger-level matrix.