Michael Gallie & Partners have over 50 years’ expertise in carrying out measured building surveys. Many people in the AEC industry don’t understand our processes and specialist equipment we use and believe we are practising the ‘dark arts’. To allay these views, below is an outline guide of our process of producing a measured building survey.
1. Access & RAMS
At Michael Gallie & Partners, we take gaining access to all areas of the building as important as the survey itself because this can impact program. With occupied buildings the client would be provided a program for how long each floor takes to measure so access can be arranged accordingly. A Risk Assessment & Method Statement (RAMS) would also be provided prior to any on-site surveys.
2. Survey Control Framework & Grid/Datum Setup
All our measured building surveys are based upon an accurate survey control framework. To relate the survey to Ordnance Survey grid and datum our surveyors use 2 No. high accuracy GPS receivers on-site simultaneously for a 2-hour period.
3. Laser Scanning
At Michael Gallie & Partners, we only use laser scanning for all our measured building surveys. All areas of the building are laser scanned fully to ensure complete coverage. This involves a surveyor with a laser scanner mounted on a camera tripod carrying out multiple setup positions across each floor.
4. Office Processing
Using specialist software, the laser scan data is processed, and the resultant point cloud is exported in manageable floor by floor chunks. The point cloud is then interrogated in either CAD or a BIM authoring software to produce the 2D or 3D client deliverables required.
5. Client Deliverable Production
For typical 2D CAD measured building survey process we use the point cloud to draw the site & ground floor plan first to set the shape of the building followed by the upper and lower floors. We then draw the 2D external elevations followed by the 2D sections. By following this methodology, we can make sure that all 2D deliverables align with each other accurately and that information is issued to the client with no issues. For 3D BIM deliverables we follow a similar drawing process but work collaboratively in larger teams on one single 3D model all at the same time.
6. Client Issue
All our 2D & 3D measured building survey deliverables are issued to the client via email or weblink download depending on file sizes. All drawing issues are accompanied with a drawing register which indicates drawings issued, versioning, date of issue and companies issued.