Contractor: Willmott Dixon Capital Works
Software: Autodesk Revit, Autodesk Navisworks and CADduct (now owned by Autodesk)
Next step: COBie, making more use of the BIM model on site
This extension to BCU’s city centre campus opens in autumn 2013
On a £48m project for a university that has teaching strengths in the built environment, it was clear that Willmott Dixon would be expected to operate close to BIM’s leading edge. ”Universities in general are good, well-informed clients and if they’re teaching the built environment, then BIM is on their radar,” says James Daniel MCIAT ICIOB, BIMM development manager.
Birmingham City University had commissioned its three design consultants with the requirement that they would work in BIM, and Willmott Dixon then won the tender on the same basis. “We had access to the M&E, architectural and structural models in the tender process, then these were handed over to us and we created an integrated model using Autodesk Navisworks project review software. As far as we know, the project was the largest single-platform BIM project in the UK,” says Daniel.
Navisworks’ capabilities included clash analysis – a term Daniel prefers to clash detection. “You analyse the issues and deal with them, there’s no blame.”
The integrated model then acted as the main reference point for the design and construction team. A fourth design – from M&E subcontractor NG Bailey, created in CADduct – was added as a federated model. “Its role involved fabricating offsite elements, so it needed the onsite information.”
But Daniel acknowledges the model had limited impact on the construction phase: it was accessible in the site offices, and there was some linkage with Willmott Dixon’s programming and planning software. But for site-based personnel and processes, it was more or less business as usual.
However, BIM will have a considerable impact on the university estate department’s ongoing FM. “Delivering the data in a BIM format was a requirement, you have to understand what the client’s requirements are and structure your data properly. [FM data transfer] is the next big thing we’ll see the industry take forward.”
At a technical level, this will involve giving the client as-built data direct from the model. “A lot of FM tools use platforms such as Navisworks to view output information, adding tags and links allows data to be tracked back to the database within the model.”
Contractor: BAM Construction
Software: Autodesk Revit
Next steps: Upskilling BAM’s in-house CAD team to fully exploit the capabilities of integrated 3D design
Strood Academy was chosen as the BIM proving-ground in BAM’s Medway Council Building Schools for the Future project. A Stage D concept design by Nicholas Hare Architects was taken on by BAM’s in-house design team which rebuilt the architectural and structural design in Autodesk Revit. M&E design wasn’t integrated on this project, although BAM has taken this step on other projects. “In every job, there’s a move forward compared with the last one,” says project manager Stuart Groom, now working on Block B for Argent at King’s Cross, in London.
The model was given a “fourth dimension” by linking the design to the construction sequencing, and there was also some linkage to subcontract specialists, with precast concrete panel manufacturer Thorp viewing the model data. “The supply chain are gearing up to use it, and are aware they have to use it to win work.”
As with Habberley Learning Campus (see page 32), rendered images taken straight from the BIM model proved their value at tender stage and in early design presentations to the client. “If a member of the teaching staff wanted reassurance about the sight lines from their classroom desk, for instance, the BIM model could instantly deliver the answer,” says Groom.
Being able to consult an integrated model clearly brought efficiencies, starting with a reduction in the number of design workshops.
The model also proved its worth in the tricky services challenge of running the water and power supply for under-window heaters in the classrooms through the bulkhead in the “teaching wall”, and giving accurate information to Thorp. “With normal 2D elevations, it sounds strange but it might be possible to miss an area. It’s not unheard of to be on the roof and say, ‘where’s that bit of cladding?’. Then you’ve got a bit of tarpaulin over the roof for three months because no one’s picked it up!” says Groom.
But he struggles to put a figure on cost and time savings. “There are definitely time and cost implications, but you’re trying to guess what would have gone wrong without BIM – that’s very difficult.”