We were recently commissioned by a Project Management team at Skanska to capture the existing state of two hospital courtyards. The aim of the survey is to provide accurate measurement data of the building facades, to enable refurbishment works to proceed efficiently knowing the raw data is reliable. The project managers require their technicians to work in Autodesk Revit throughout the design stage, therefore a BIM ready Revit model must be produced for the existing phase from the laser scan data.
We collected the initial raw data with our Faro X130 using a combination of full colour and greyscale scans. This provides both image quality for analysis of existing materials and improves alignment accuracy of the point cloud while allowing for an on site efficient work flow. We controlled the accuracy of the scan data position using Targets and coordinates collected using a Leica Total Station. The total time on site for this project was approximately 3 hours including roof access.
One of the main deliverables for this project was an accurate point cloud which the project managers could use not only for an accurate existing building record but also to take varying quick measurements of windows, panels and overall geometry without having to regain access to the site. To produce this we needed to register the scan data to an indexed .rcp format by piecing each scan together to form a unified point cloud suitable for analysis in various software along with Autodesk Recap and Revit.
Following production of the point cloud we insert it into Revit with the correct shared coordinates, this enables us to carve sections and slices through the point cloud to check the alignment accuracy and start effectively tracing the scan data with building elements. We created a number of system families for walls and roof elements which indicated they were not surveyed intrusively only allowing for overall thickness between the surveyed surfaces. The windows and doors were not ones we had produced previously so needed to be built in a bespoke fashion, to enable future use they were built natively in Revit using fully flexible parameters to allow overall dimensions to be easily changed without the family breaking.
The overall finished product was simple, but BIM ready as it was produced natively in Revit with fully flexible and intelligent components, each component was placed on the correct "Existing" building phase and the initial views and sheets within the project were set up with our company title sheets and ownership. The Project Management Team within Skanska can now effectively pick up the project where we left off to start producing the proposals.