GIFA Surveys – 32 ESFA PSBP2 Schools, ~250,000m²
Capturing large areas of the school estates as part of the ESFA PSBP2 school building programme core surveys required a different approach to the traditional disto based survey method.
During 2017 the second phase of the priority schools building programme accelerated. SUMO provided both the Utility/Topographic and the gross internal floor area core surveys. This case study describes our innovative use of mobile scanning to capture data much faster than was previously possible. Plus the use of BIM software to create a coordinated set of drawings and schedules for each project.
What were the challenges:
- The number and scale of schools that required surveying meant that the historic approach of surveying during school holidays was not suitable.
- Traditional methods of survey produce CAD output. However, non-graphical data cannot be added and so has to be coordinated manually.
How were they overcome:
- Using hand held laser scanning we captured the largest sites of up to 13,800m² in just two days each and the smaller sites of 1,200-4,500m² in just a few hours after the schools were vacant in the evenings.
- By using BIM software we captured the geometric data of the rooms from the laser scan and then added the non-graphical data such as room name, number and ESFA block designation. This was scheduled from the model combining room areas and heights from the model.
Timescale and delivery benefits:
The workflow was tested to its limit with the first 5 schools totalling over 50,000m². The smallest school measured just over 6,000m² and the largest over 13,000m². Despite this, site work was completed in under two weeks by a single operative using a mobile laser scanner. Data was captured in blocks of around 1,000-1,500m² with a revolving process of registering data on site while the next block was being captured. This work process allowed the data to be checked for gaps or errors and re-scanned before we left each site, if necessary. Benefits to using this method of data collection also include the flexibility of working-times. Due to the efficient workflow of the technique, we were able to scan and collect data at a time suitable to the client. In this case it was during the evenings when the school was closed and meant there was no disturbance to the usual running of the school.