Analysis

Interview: AHR’s Allan Hunt – Making BIM work for refurbishment

One 200-seat lecture theatre scheme was valued at around £100,000. Most people would say you shouldn’t be using BIM for this scale of project, but we disagree.– Allan Hunt, AHR-Global

Allan Hunt, a chartered building surveyor and director at architect and building consultancy AHR, on the challenges of implementing BIM on small-scale refurbishment projects at the University of Sheffield.

How long has AHR-Global been using BIM?

AHR-Global comprises eight UK offices and was formed last year following the split of international architect Aedas. Aedas started down the BIM road in 2007/2008, switching its designers over to Autodesk Revit. I head up AHR’s building consultancy practice and a team of building surveyors. Because we had access to this BIM technology, we could jump straight into it. If we had been a more traditional building surveying business I’m not sure we would be using it to the extent we are now.

What work for the University of Sheffield has utilised BIM?

Over the past three years we have completed a series of teaching space refurbishments, including 22 lecture theatres and seminar rooms, collectively worth over £1.5m, but individually worth much less. For example, one 200-seat lecture theatre scheme was valued at around £100,000 and the refurbished Bradfield Field Station (pictured above), located on the moorland above Sheffield, cost £200,000. Most people would say you shouldn’t be using BIM for this scale of project, but we disagree.

Are university clients well versed in BIM?

BIM is well understood when it comes to new build, or large-scale refurbishment projects, but it’s difficult for universities to know where to start when working with existing estates and tackling the regular churn of small-scale refurbishment projects. As a result, we have introduced BIM to them.

To what extent have you been implementing BIM?

Using Autodesk Revit, we import 3D laser scan data recorded by our geomatics engineers, and apply all the new finishes to internal elevations, windows, doors and other elements, such as artwork the university wants to have installed. We use the model to drive all the design schedules and use it for 3D design coordination and clash detection, which can be a horrendous issue on a refurb project.

We have been running a form of “lonely” BIM, without a federated model or input from any of the other design team partners or suppliers. In our experience, there hasn’t been enough buy-in from designer partners, including the M&E side, on small-scale projects.

While it might not sound like we are using BIM to its full potential, it’s really about getting that client on the road to full BIM. My mantra at the moment is: “Just because we can’t do it all, that doesn’t mean we shouldn’t do some of it.”

A total of 22 lecture theatres have been completed using BIM

What have been the biggest BIM “wins” to date?

The visualisation side of things, particularly as a tool for stakeholder engagement – for example on a lecture theatre refurb you are liaising with academic staff, room booking staff, students and others. In the past we had to rely on just a 2D plan and maybe some sample boards and hope they could imagine schemes, now they can see it in 3D directly.

It has also made things a lot better for us in terms of reducing amendments, because once you change something in the model it is changed across all the drawings. We’re getting less errors and producing better-coordinated information.

What has been the biggest lesson learnt?

Just because your client isn’t ready for Level 2 BIM and doesn’t have the FM systems in place to make full use of the data, that shouldn’t mean you don’t start the process. It’s certainly hasn’t cost us any more money to offer this service.

Doesn’t constructing a 3D BIM model involve a lot of input for a small refurb project?

Not if you only build section of the model related to the area you are refurbishing. And if you are doing subsequent projects on the same building it is not long before you have a full model of the asset you can use in the future. Then it is no longer a case of having to build the model again, it just gets tagged into future workflows, which means clients don’t have to pay for that design work again and so they get better value out of their programmes.

What are your plans for the future?

What we are trying to do with Sheffield University, and our other clients, is encourage them to bring in BIM expertise to improve project work flows. Then there’s the whole FM piece about taking BIM beyond the construction phase, just because the client is not ready for it yet, it doesn’t mean you shouldn’t be trying to do it anyway, sooner or later they will be ready for it.

A target should be the pioneering work done by Western Michigan University in the US, which has modelled its entire estate in BIM. It has saved an absolute fortune on the FM side.

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