Phil King, Design Director, discusses the opportunities BIM can bring to the future of the built environment.
The Building Information Modelling (BIM) revolution is well underway. The UK Government has set a target to reach BIM Level 2 on public sector work by 2016, private sector clients are increasingly requesting BIM on their projects and the construction industry has been busy equipping itself with the systems and processes necessary to make it standard practice.
BIM improves the way that the industry works together, leading to better collaboration, coordination and exchange of information. For the client, it helps to mitigate risk, reduce costs, minimise waste, shorten programme and smooth handover and facilities management.
For the MEP (mechanical, electrical and plumbing) engineers, it means early involvement and a lot more detailed work at the front end, giving us the biggest opportunity we’ve ever had to reduce overall construction time and cost through the MEP services design. It also means that a higher volume of pre-fabrication and modularisation is achievable within the timescales, with benefits in quality, reduced snagging time, speed of installation and economies of scale.
BIM in practice
BIM is a shared, digital representation of physical and functional characteristics of a built object, on which critical project decisions can be based. When we reach Level 3 BIM, we’ll be using a fully integrated and collaborative process enabled by web services and using 4D construction sequencing, 5D cost information and 6D project lifecycle management information.
This means inputting more information and detail in the design phases, which takes up more resources. In fact, it marks a more fundamental shift in the way we’ve always looked at the costs associated with building projects.
Traditionally, the costs associated with each stage look like this:
Design 1 Unit of Cost
Construction 10 Units of Cost
In Occupation 100 Units of Cost
Using BIM, they look more like this:
Design 1.5 Units of Cost
Construction 8 Units of Cost
In Occupation 90 Units of Cost
Interestingly, this new cost structure supports Paul Morrell’s change programme, achieving both greater integration and a 20% reduction in building costs, not to mention the savings in operation.
With such a change in the overall cost structure should come a change in emphasis in the professional team’s fee structures. More time and effort at the design stage and less in construction should be reflected in the fees awarded. In reality, to achieve this we’ll need to be able to quantify money saved during the construction and operation stages as a result of early involvement.
Changes to contracts will inevitably come too. With lots of information comes liability, so appointments and building contracts need to encourage an open culture and cover the use of BIM as well as outputs (2D drawings, specification, 3D model or all three), responsibilities, including transfer of the model, and liability.
There should be a single owner of the 3D Model during the design and construction stages so all parties contribute to one model, avoiding confusion and delays. Additional responsibility and liability impacts would need to be reflected in the owner’s contract. On handover to the client, agreement on how the model will be updated after practical completion is needed.
Lastly, there’ll be a change in how we work together – engineer to engineer. There will be greater coordination between mechanical engineers, electrical engineers, public health engineers and BIM operatives. We’ll need to think in 3D, work in areas not systems and eliminate paper mark-ups, using the software instead.
We’ll also use BIM to do much more, including the creation of 3D Geometric models for the following:
- DTM – Dynamic thermal modelling
- CFD – Computational fluid dynamics
- Comfort studies
- Pedestrian Wind comfort analysis
- Natural ventilation studies
- Fire & Smoke modelling
- Acoustics modelling
- Part L assessments
- EPC Assessments
BIM is an opportunity, not just for engineers and the built environment as a whole, but for the government too in meeting its cost reduction targets. Its success now and in the future depends on people, processes and the technology itself. But it won’t happen seamlessly and, as with any new technology and process, we’ll all need to evolve.