The potential of BIM to reduce waste during design and construction (part 1/2)

Today I chaired and presented one of the Better with BIM seminars at ecobuild. Can BIM be used to reduce waste during design and construction?

Ultimately, in my opinion, this question boils down to the simple fact that with better information, more informed decisions can be made. Taking this away from construction for a moment, could you eat more healthily if the content of your food was labelled more clearly? The answer is clearly “yes”. And this is analogous to construction – the information about the objects that buildings are built from must be better. This will allow us to build better buildings, lower energy use, less waste and cheaper.

I include a few screenshots, below showing better information delivered to designers around recycled content. This is possible through well-structured information. Better information from manufacturers can be delivered. Information from different providers can link together to produce a more coherent information set.

Fig 1 – Standard guidance on recycled content

Fig 2 – Suggested values for each product on market values

Fig 3 – Actual values from product manufacturers

Where this standardised information becomes even more valuable is when analysing this content in the context of a building model. By performing digital take-offs from multiple objects the benefits of consistency of information become clear.

Software functionality can also help. Where standardised objects sizes are included then “clever apps” can instantly show information. If plasterboard is 2400mm high for example, then partitions can be highlighted where cuts will have to be made. Spaces can be optimised to ensure that waste is minimised.

Fig 4 – Standardised properties

Waste on site can be reduced further if whole assemblies can be fabricated off-site. Within the factory, the design of these assemblies can be optimised. This means that the construction process on-site has a greater proportion of “assembling” and less “building”.

The screenshot below shows a model representing a standard column assembly from the Laing O’Rourke manufacturing plant. Models, guidance and standard specifications such as these can be given to design teams early in a project. The time savings are obvious as are the environmental impact benefits. Waste on site is clearly only part of this overall picture.

Fig 5 – Standardised BIM objects

So in conclusion, the digital information revolution is happening. Where information is well-structured, designers can then make well-informed decisions that can help reduce the environmental impact of buildings. And finally, where factory built assemblies can be used then the information can be even better controlled and issues such as waste-on-site can be greatly reduced.