Service 02
Topographical & engineering surveys
Detailed ground-surface mapping, engineering control and setting-out for design, drainage and construction.
Overview
A topographic survey records the physical features and elevation of a site ground levels, existing structures, vegetation, drainage lines and services as a scaled, contoured drawing that architects, engineers and planners can design against with confidence. The same control network then carries the design back onto the ground: setting-out puts building corners, grid lines, levels, road centrelines and drainage inverts in their correct position so that what gets constructed matches what was drawn, within the tolerance the works demand.
Our services include
- Topographical surveys
- Engineering surveys
- Control surveys
- Setting-out surveys
- Construction surveys
Typical approach
We capture the site using a combination of GNSS RTK and total station observations, tied to a known datum so the survey can be combined with adjoining data or a later stage of the same project. Levels are taken at a density appropriate to the terrain and the intended design use, and every visible feature relevant to the brief boundaries, existing buildings, manholes, trees, retaining structures is located and classified. Working from the engineer's or architect's coordinates, we then establish control points around the site and set out the required features, re-verifying critical lines (foundations, structural grids) before concrete is poured a mistake caught before that point is a correction; after it, a demolition.
What a client receives
A digital topographic drawing (typically DWG and PDF) with contours, spot levels and feature layers separated for easy use in design software, a summary of the datum and coordinate system used, marked-out points and lines on site where setting-out is involved, a setting-out record for the contractor's and engineer's files, and on request as-built verification once construction elements are in place.