Services
What we survey, and what you get back.
Each of these is priced against a stated tolerance and a stated deliverable. If a brief needs something we do not hold in-house, we will say so and name someone who does, rather than subcontracting it quietly and putting our cover sheet on it.
01
Topographic survey
Typical: 2–4 field days for a 5 ha site, drawing issued within five working days of leaving site.
Detail and levels across open ground: kerbs, drainage, trees with canopy and girth, services covers, boundaries as found, and a levelled surface you can cut sections through. We survey what is there on the day and note what we could not reach, because a drawing that quietly interpolates across a hedge is how a retaining wall ends up in the wrong place.
Everything is tied to a control network first, so a phase two survey eighteen months later drops straight onto phase one without a fudge factor.
| Datum | OSGB36 grid and ODN levels, or an agreed site grid |
|---|---|
| Tolerance | ±15 mm plan, ±20 mm level, to site control |
| Scale | 1:200 to 1:1000 depending on detail density |
| Deliverables | DWG, PDF, DTM surface (LandXML or 3D faces), control schedule |
02
Measured building survey
Level 1 through Level 4, to the RICS measured survey specification.
Floor plans, sections and elevations of the building as it actually stands, including the parts that are out of plumb, out of square, or three courses lower than the drawing from 1974 says. Historic and listed fabric is scanned before it is drawn, so every line can be checked back against the point cloud.
We draw wall thicknesses as measured rather than as assumed, and we mark where a void or a cavity prevented a direct measurement. Both of those cost half a day and save an argument on site.
| Capture | Terrestrial laser scan plus total station control |
|---|---|
| Tolerance | ±10 mm on structure, ±25 mm on decorative detail |
| Detail | Level 1 (outline) to Level 4 (full fabric record) |
| Deliverables | DWG or Revit, registered E57, rectified elevations |
03
Bathymetric & hydrographic survey
Estuaries, harbours and inshore work from the Menai to Aberdyfi.
Single-beam for channel sections and volumes, multibeam where the bed shape matters — scour around a pier, siltation in a berth, the toe of a sea wall. Both are reduced against our own tide gauge on site rather than an interpolated prediction, which on this coast can differ by a quarter of a metre in a strong southwesterly.
Land and water are surveyed on one datum. A sea defence job where the beach survey and the bathymetry meet on different vertical references is not two surveys, it is one survey with a gap in the middle.
| Standard | IHO S-44 Order 1a, or Order 1b for reconnaissance |
|---|---|
| Vertical | ±25–50 mm at 12 m, including tidal reduction |
| Reduction | ODN and Chart Datum, from a gauge deployed for the survey |
| Deliverables | XYZ, gridded surface, contoured chart, volume report |
04
UAV photogrammetry
CAA operational authorisation held; flight logs issued with the survey.
Aerial capture where ground access is slow, unsafe or would take a week: quarry faces, roofs, active earthworks, forestry tracks, coastal cliffs. Every flight is run against ground control targets that we survey in with a total station, because a photogrammetric model floated on the aircraft’s own GNSS is a picture, not a survey.
Volumes from repeat flights are the common use — stockpiles, borrow pits, landfill cells — and we report the change surface with a stated confidence rather than a single number with no error bar on it.
| Flight height | 40–90 m AGL, 1.2–2.5 cm ground sample distance |
|---|---|
| Tolerance | ±25–35 mm to ground control |
| Control | Minimum five targets, surveyed and checked independently |
| Deliverables | Orthomosaic, DSM, classified point cloud, volume report |
05
Setting out & as-built
Retained through the build, not booked one visit at a time.
A control network observed and least-squares adjusted at the start, witnessed so it can be recovered when a station gets buried, and re-observed at agreed intervals through the programme. Setting out is then done from the design model directly rather than from scaled dimensions off a drawing.
As-built checks are issued the same day, with a deviation report against design rather than a bare set of coordinates. If something is out, the contractor finds out while the shutter is still up.
| Network | Least-squares adjusted, residuals published |
|---|---|
| Tolerance | ±3 mm structural, ±10 mm external works |
| Recovery | Witness diagrams for every station |
| Deliverables | Setting-out schedule, as-built model, deviation report |
06
Structural monitoring
Trigger levels agreed in writing before the first epoch.
Movement watched over weeks or months on retaining structures, quay walls, bridges and buildings adjacent to deep excavation. Periodic monitoring by total station and precise level, or an automated installation reading around the clock where the risk justifies it.
Amber and red triggers are set with the engineer at the outset. When one is crossed, a named person telephones — the report follows, but the call comes first. A monitoring contract where a red trigger arrives as a spreadsheet attachment on Monday morning is not monitoring.
| Precision | ±0.5 mm level, ±1.5 mm 3D on prism targets |
|---|---|
| Frequency | Continuous, daily, weekly or by event |
| Reference | Stable datum stations outside the zone of influence |
| Deliverables | Epoch reports, trend plots, trigger notifications |
07
Utility detection to PAS 128
Quality level stated per utility, not averaged across the site.
Electromagnetic location and ground-penetrating radar to find what is already under the site, surveyed in to the same control as everything else and attributed with the quality level actually achieved on each run. A drawing that mixes QL-B and QL-D without saying which is which is more dangerous than no drawing, because it will be trusted.
Where the survey cannot resolve something — deep ducts, reinforced slabs, saturated ground — it is marked as such and we recommend trial holes rather than guessing a depth.
| Method | EML sweep plus GPR, dual frequency |
|---|---|
| Quality level | QL-D desktop through QL-B2 detected and levelled |
| Marking | Site marked to the client’s colour convention |
| Deliverables | Attributed DWG, GPR record, QL statement per utility |
08
Boundary & Land Registry plans
Plans prepared for registration; expert determination on request.
Title plan comparison against the physical boundary as it stands, measured and drawn to a scale the Land Registry will accept, with the discrepancies set out plainly. Most boundary disputes are a hedge that moved forty years ago and a general boundary that was never determined.
We will tell you when a survey cannot settle the question — because the evidence is legal rather than geometric — before taking a fee to measure something that will not decide it.
| Scale | 1:200 or 1:500, north point and dimensions shown |
|---|---|
| Basis | OS MasterMap overlay, title plan, and measured position |
| Output | Land Registry compliant plan, discrepancy schedule |
| Note | Determined boundary applications supported |
Not sure which of these you need?
Most enquiries arrive describing a problem rather than a survey type, which is the right way round. Tell us what the measurement has to decide and we will tell you the cheapest thing that will decide it.