This is the first in a series of conversations, or ‘BIM Chats,’ with construction industry stakeholders in South West UK. The aim is to provide practical insights into how the construction industry, its clients and delivery teams at the 'coal-face' are engaging with Building Information Modelling (BIM) since the UK Government mandated BIM level 2 on public sector projects over £5M.
September 2016 I met with Andrew Simpson at NVB Architects, a medium sized
practice with strong roots in the education sector, to discuss how they were
faring with Building Information Modelling (BIM) and what systems they had
adopted for BIM management. The practice currently employs 25 staff and has
been using Autodesk Revit for 3.5 years.
Image: Leighton Park School, Reading, NVB Architects, Mann Williams Structure, Method Consulting
Structure and Services Integration
Andrew noted that architects and structural engineers have particularly close working arrangements, which reflects the integration between these elements of work. He noted however that things were not the same with service engineers who frequently do not undertake detailed design, but rather work on performance specifications – without a technical model of the installation. The use of these specifications mean that opportunities to coordinate the BIM model are lost or reduced. As a direct result NVB are now frequently using installation subcontractors (who have suitable design skills and BIM capability) to provide technical design, installation models, and market pricing during RIBA stage 4. Andrew noted that this was a paid service, but that costs were discounted if the subcontractor subsequently secured the contract at the tender stage.
Andrew noted that BIM models can be temperamental if significant changes are made, such as happens during RIBA stages 2 and 3. He therefore outlined that project teams would frequently re-draw a project (from scratch) at RIBA Stage 4 to avoid carrying forward legacy problems from earlier iterations. He explained that this was usually a fairly quick exercise, and that delivery teams had more confidence in the predictability of the ‘clean’ model.
RIBA stage 4 (Technical design)
NVB BIM-manager (Kenny Fox) noted that NVB do not currently host a central ‘live’ model for all consultants to work on. This is partly a result of slowness of the models access via the internet, but also to avoid confusion between consultants with elements constantly updating. NVB therefore circulate a copy of the current model every two weeks, via a FTP server such as Dropbox, which is used by the consultants, keep a record of fixed elements (such as gridlines, external walls etc), and then meet to review design development.
BIM level 3 (Open BIM)
When asked about the future and NVB Architect's plans to engage and invest in BIM Level 3 process and technology, Andrew explained that:
“…at the moment, design teams appear to be working very well with BIM level 2 using separate models which are combined and coordinated at key stages. Level 3 (open BIM) adds a layer of complexity that we are not sure how to handle, introduces technical difficulties with regard speed of use, and for now we feel its benefits are unclear“.
Standardised BIM libraries and components
Andrew noted that rather than focus on level 3, he thought it more important that the wider supply chair develop a comprehensive BIM library of components based on common guidelines and quality standards. Guidelines that avoid individual families (drawing components) becoming overly complicated and are focused on what designers and facilities managers require.
Kenny noted that there was a good range of free (or comparatively cheap) plugins available for Revit. He did note however that some of the more complex tools – such as those for snagging appeared too expensive and He also made it clear that the investment required for some of the latest digital tools was currently out of reach for their size of architectural practice although he agreed that the need was definitely there to render the industry more productive.
Top Down or Bottom Up?
When asked whether NVB Architects felt there appeared to be a need for improved BIM education and better understanding of existing guidelines such as the PAS 1192 suite to improve BIM processes ‘top- down’ or whether it was more a question of waiting for the whole supply-chain to develop together from the ‘bottom-up,’ Andrew stated that both were important.
Future change driven by client ‘pull’
Andrew noted that a small but increasing number of clients in the education sector have indicated an intention to purchase BIM software such as REVIT and for Cad Assisted Facilities Management software (CAFM) such as Planon to be updated to incorporate BIM inputs. They are doing this in order for their estates and facilities management (FM) teams to be able to more easily access the facilities information which is increasingly held in the construction model.
Image Credit: NVB Architects
NVB Architects is an award-winning RIBA Chartered Practice based at Rook Lane in Frome, Somerset and a member of Constructing Excellence South West.
By: Mary Bon RIBA | AEC Collaborator