[email protected] | 020 8935 5160
Need a quick price for your project? Get a quote
[email protected] | 020 8935 5160
Need a quick price for your project? Get a quote
A movement monitoring survey measures structural movement in a building, retaining wall or earthwork over time. Survey targets, prisms or sensors are fixed at agreed positions, then resurveyed at set intervals using high-precision total stations, digital levels or automated sensors. Each round of readings is compared against an initial baseline, producing tables and graphs that show vertical, horizontal and 3D coordinate movement to within 1mm.
If movement crosses a predefined trigger threshold, the project team is notified immediately so works can be paused, reviewed or remediated. The result is a defensible, documented record of how a structure responded throughout the works. That record protects the engineer’s design assumptions, supports party wall awards, satisfies insurers and gives the contractor evidence if a third-party claim is made.
We are appointed almost exclusively by professionals in the construction industry. Our typical clients are:
Our process, reporting format and pricing structure are built for professionals who need clean data, on time, in a format you can drop straight into a report or party wall award.
The bulk of our London work. We baseline the affected and adjoining structures, monitor through dig-down, underpinning, raft pour and waterproofing, then taper off frequency through fit-out.
Both the structure being demolished and any retained or adjoining buildings. Often combined with vibration monitoring on neighbouring assets.
Including bored piling, CFA, mini-piling and vibro-compaction. We typically combine prism monitoring of structures with PPV vibration monitoring at neighbour boundaries.
Including projects close to TfL, Thames Water and Network Rail assets where third-party agreements set explicit movement triggers.
Long-period monitoring (often 12 months or more) to evidence whether a structure is still moving following a heave or subsidence event.
Where intervention thresholds are tight and reporting standards are scrutinised by conservation officers.
1-second Leica total stations observing reflective targets or mini-prisms from a stable off-site control network. Typical 3D accuracy of plus or minus 1mm at normal building distances. This is the workhorse method for most basement and demolition jobs.
Leica digital barcode levels reading invar staves or wall-mounted BM points. Vertical accuracy of plus or minus 0.5mm. Used where vertical settlement is the primary concern, for example over running tunnels or above large excavations.
A robotic total station mounted in a fixed enclosure, set to observe a network of prisms at programmed intervals (often hourly). Data uploads to a cloud dashboard with email and SMS alerts when triggers are breached. Suited to higher-risk works, longer durations or sites where weekend access is restricted.
Wireless inclinometers fixed to walls, columns or temporary works. Continuous readings, typically every 15 minutes, with threshold alerts. Useful where the failure mode is rotation rather than translation, for example on retaining walls or scaffolds.
Tri-axial geophones recording peak particle velocity in line with BS 7385 and BS 5228. Real-time data, alarm thresholds set in agreement with the engineer or party wall surveyor, and 24/7 SMS or email alerts. We deploy these for piling, demolition, vibratory compaction and breaking-out works.
Demec studs measured with a Mitutoyo digital gauge for sub-millimetre crack movement, plus telltales (Avongard or similar) for visual indication. Often run alongside structural monitoring on the same site. Read more about our crack monitoring service.
We charge per visit on a clear, line-item basis. No retainers, no minimum contract length, no surprise mobilisation fees.
For commercial, infrastructure or international projects the figures will be higher. The same per-visit logic applies.
Building movement can occur for many reasons, including nearby construction, changes in ground conditions or the natural settlement of a structure.
Without accurate monitoring, even small shifts can go unnoticed until visible cracks or costly damage appear. Regular monitoring provides early warning of these issues, allowing prompt action before they escalate.
It also offers documented evidence for insurance, legal or party wall purposes, helping to protect all parties involved.
As noted by
The Survey Association (TSA)
“accurately measured data has always been vital for a successful building project.”
Reliable monitoring ensures the same level of accuracy throughout a structure’s life, supporting safety and sound decision-making.”
We carry out movement monitoring surveys throughout London and the South East, with regular work in Essex, Kent, Surrey and Hertfordshire. We also undertake projects further afield in the UK and have worked internationally, including major infrastructure monitoring at the Port of Monrovia.
For London specifically, our teams cover all 32 boroughs. Most of our basement-related work is in the central and west London boroughs (Westminster, Kensington and Chelsea, Hammersmith and Fulham, Camden, Wandsworth, Richmond), but we are equally happy mobilising to north, east or south London.
For a full step-by-step breakdown, read our guide: How Does a Building Movement Monitoring Survey Work?
Before any works begin. Always. A baseline taken after enabling works have started is not a baseline, it is a midpoint, and any movement that occurred during enabling works will be invisible. We need a minimum of two pre-works surveys to establish a defensible baseline.
Plus or minus 1mm in 3D for total station observations of prisms at typical building distances. Plus or minus 0.5mm vertically for precise levelling. Automated systems achieve similar accuracy with the advantage of continuous data.
Driven by the works, not the calendar. Weekly during heavy operations such as excavation, underpinning and piling. Fortnightly or monthly during steel erection, slab pours and similar. Reduced further during fit-out. We agree the schedule with the appointed structural engineer or party wall surveyor and can adjust week to week if site conditions change.
Triggers are project-specific and should be set by the structural engineer based on the structure’s tolerance, not by the surveyor. Typical residential basement triggers in London sit in the range of 5mm amber and 10mm red for total movement, but heritage buildings, masonry arches and assets with third-party agreements (TfL, Network Rail, Thames Water) often need much tighter values.
Yes. Provided it has been collected from a stable, independent control network, with appropriate baselines and reported consistently, monitoring data stands up in party wall disputes, third-party damage claims and insurance assessments. We have produced data used in expert witness reports.
The biggest savings come at the specification stage, before any monitoring is appointed. Reducing the number of monitoring points, simplifying the control network setup, and matching visit frequency to actual works intensity all cut cost without compromising the data. We are happy to review a draft specification and suggest economies before you commit.
Typical basement projects: 6 to 18 months. Insurance subsidence cases: often 12 months minimum to span a heave cycle. Major infrastructure projects: multi-year. There is no upper limit in our process and we have schemes running for over five years.
Most of our work is in London and the Home Counties. We cover all 32 London boroughs and have run schemes across Westminster, Kensington and Chelsea, Camden, Hammersmith and Fulham, Wandsworth, Richmond, Southwark and the City, with regular projects through Essex, Kent, Surrey, Hertfordshire and Berkshire.
We also mobilise to the Midlands, the North and Scotland on a planned basis, usually combining the install visit with the first round of monitoring to keep travel costs sensible. Internationally we have undertaken monitoring as far afield as the Port of Monrovia in West Africa. If you are unsure whether your site is within our usual reach, send us the postcode and we will confirm coverage and a mobilisation cost within the day.
We help our clients monitor cracks that are potentially opening or closing. We install demec studs or gauges to accurately record movement over time.
Following this we produce detailed reports and graphs illustrating the movement in a clear and consise manner.
Email: [email protected]
Call: 020 8935 5160 (Monday to Friday – 09:00 – 17:00)
Essex Office:
92 Bellhouse Ln, Leigh-On-Sea, Essex, SS9 4PQ
London Office:
76 Quill Street, Islington, London, N4 2AD
Typical reply within 24 hours, Mon–Fri
