As-Built Laser Scanning of listed Scarborough Market
Programme saving and increased accuracy for Grade II listed Scarborough Market Hall
Capita Design are the market leader in strategic partnering with UK local authorities, providing a wide range of managed services including property, highways, regulatory services and development control. Capita Design required an accurate ‘as-built’ computer model of Scarborough Market Hall as part of a £2.5 million refurbishment proposal for Scarborough Borough Council so came to Hobs Studio for As-Built Laser Scanning services.
This as-built model needed to solve a few problems. It needed to show the existing state of this Grade II listed building and there was a desire to reduce surveying time and save on costs where possible. The existing 2D CAD drawings were unreliable, and Capita would be designing the project in 3D Revit software so the model needed to also operate in this software. The model was also required for RIBA (Royal Institute of British Architects) Stages 2 and 3 for BIM projects.
A 3D As-Built Laser Scanning survey was completed by Hobs of the entire structure alongside a photographic scan. The hall was accessible to the general public during the scanning process and the scanning didn’t interfere with any of the market halls operations.
The resulting ‘point cloud’ data enabled the production of an as-built model of the existing building. The photographs taken at the same time were combined with the data to create photo metric images. These allowed a detailed internal study of the space for heritage purposes and a greater understanding for both client and officers of the level of degradation in the original interiors. This reduced risks for both Scarborough Council and Capita.
As this is a Grade II listed building, the data enabled detailed discussions with English Heritage about refurbishment methods and changes in the fabric of the building. English Heritage were able to fully see the building in its context and fully understand the existing condition.
The as-built model allowed Capita to test their planning data at RIBA stage 2 before submission and a set of clear existing drawings was also created from the as-built model. The Laser scanning also recorded the existing internal layout, alterations and existing damage to the building. The resulting as-built model was eventually used into RIBA Stage 4 as the project progressed.
By comparison a traditional survey would have been from eye and window level and limited in its detail use. Chris Boyce, Capita Design Director, explains “Whilst levels and risk would have been mitigated, we would have spent around 100 man hours on a traditional survey and the outcome would have been a lesser quality representation of the existing structure with more margin for error. The design team would also have spent much longer integrating our Revit model into the existing building.”
As-Built Laser Scanning enabled a programme saving of two weeks in pre-planning and the detail design was risk-free due to the level of data gained at this initial stage.
Chris Boyce, concludes “We chose Hobs Studio for their speed, efficiency and value. The experience was excellent and the team were flexible and intelligent in the work. Going forward all of our key projects that involve existing buildings will use this service.”