Mind the gap Can BIM bridge the gulf between design intent & building performance?
18th July 2016
When you work in construction, you know that programme slippage is always a risk. Gaps have the potential to crop up everywhere.
At the latest Constructing Excellence Sussex event – Building Performance Evaluation – Performance Gap and the role of BIM the focus was on energy. Built environment specialist Mat Colmer, from Innovate UK made it clear that buildings are falling short of expectations when it comes to energy use, carbon emissions and airtightness. Even in ‘energy efficient’ examples, there is still a gap between what the designers originally intended and how it works out in real life.
And it’s not just energy.
As a consultant, you might have to deal with a hole in the budget. Deadlines can slip and you find yourself tackling an unforeseen gap in your work schedule. Or you’re on site with clients who say irritably, “Did it really look like this in the drawings?” Then you realise that in the move from 2-D plans to 3-D reality, something’s been lost in translation. Fairly or unfairly, there’s a yawning gap between what your client had hoped for and what they are actually getting.
Blame skills, systems or sharing?
The message from Mat was clear. It’s not about skills. People are, in the main, doing their jobs properly.
The slippage occurs when:
- companies don’t have systems to collect the right information and
- even when they do have the right data they are not sharing it consistently.
In a two-year study on building performance evaluation, Innovate UK researchers found that if plans changed during the course of a construction project, the modelling tools were not updated on a regular basis. So people weren’t learning from their mistakes or their successes, because there was no feedback loop.
Say goodbye to crossed wires – and ducts going through beams.
It’s hardly surprising that vital information goes missing on a project, when so many stakeholders – engineers, designers, project managers, clients – are involved. That’s why we’ve invested in different aspects of building information modelling, including Navisworks for project planning and Revit design software. Revit’s 3-D visuals make communication with colleagues so much easier. MacConvilles director Charles Haywood, is also Chairman of Constructing Excellence Sussex:
“When we work with other consultants using BIM-ready software, we can co-ordinate the design better. One of the traditional problems on construction projects was lack of co-ordination of the design from different disciplines. The architectural design and engineering design were not necessarily compatible – but you would only realise that when the builder was appointed. He would come on site and say, ‘I’ve got a great downstand beam here that the structural engineer has designed and it has a ventilation duct going through it. So what do you want me to do? Shall I drop the duct below the beam, which cuts the head height of the room? Or do I drill a hole through the beam and put the duct through the beam?’
How BIM helps us to help you.
“Now, you can have a design team meeting and say, ‘Right, you’ve overlaid this drawing and we can see there is a problem here. How do we resolve it?’. So everything can be resolved before you get to site and you avoid all those extra costs, delays and disappointment.”
As a practice, we’re in favour of feedback loops, so we’ll be sharing what we learn from BIM over the coming months in this news section. In the meantime, if you have a construction or design project that is taxing your team, we’d be delighted to explore options with you. Contact us today on 01273 692611.
Finally, if you’re interested in BPE, we recommend:
Innovate U.K.’s Building Performance Evaluation page: https://connect.innovateuk.org/web/building-performance-evaluation
The unabridged Business Performance Evaluation reports are here: https://www.gov.uk/government/news/new-website-hosts-wealth-of-data-on-energy-efficient-buildings