Building information modelling is becoming increasingly popular but may present problems for some lighting designers. Ruth Slavid explores the obstacles and outlines the solutions to help you find your way through the modelling maze
There are few subjects that are talked about so much, or understood so little, as building information modelling (BIM). In the lighting community, in particular, it is the subject of some dread since few have engaged with the topic but many are aware that it is something they are going to have to get to grips with – at least they are if they want to work on publicly funded work, large contractor-led work and, increasingly, large overseas projects.
For Speirs+Major, for example, which is just embarking on its BIM journey, the pressure is largely international. Design associate Iain Ruxton, who wrote about the subject in our April issue (Lighting, April 2013, page 126) says: “We are being pushed quite hard in that direction by projects outside the UK. One is a privately funded project in the US, and others are airport projects in Europe.”
Ruxton feels there is little knowledge or help available. “What is happening to us,” he says, “is that people are saying, ‘we have got everything in Revit’. They want to give us the Revit model and for us to take what we want out of it.”
Does size matter?
As a medium-size practice, Speirs+Major finds the investment in Revit – both the software and training, which is essential – just about affordable. But for much smaller lighting designers, Ruxton is concerned it will be unaffordable and that, as a result, they will find themselves excluded from vast tranches of work.
There may be a way around this, however. Large contractor Balfour Beatty for example, which has made a major
commitment to BIM, has negotiated global licences for Revit and Microstation. The company is happy to work with consultants who have no previous experience of BIM and to allow them to work on site on its software, simply investing in their own training. “They just have to realise that they want to change,” says Chris Millard, the company’s business efficiency director. “They have to be proactive and say they want to do BIM on this project.”
Yet, it may be that designers don’t need to invest in Revit or any of the other 3D architectural packages at all. The government’s BIM task group is clear that its definition of BIM is not to do with software but with a cooperative way of exchanging information, which should yield benefits through the design and construction of a building and, even more, through its operation and maintenance. It has said it wants all publicly funded projects to be delivered using at least Level 2 BIM by 2016.
The government’s definition of Level 2 BIM is that information is produced by a range of proprietary 3D tools in the different disciplines, then exchanged between those disciplines through a system known as COBIE – Construction Operations Building Information Exchange. COBIE is a protocol that defines several ‘data drops’ in which specific information has to be exchanged at specified points in the project. In addition, as it is a simple spreadsheet, in theory at least, it is not necessary for everybody who is working in BIM to be using a 3D model. As clients and contractors are looking for BIM drawings in Revit however, if some specialists, such as lighting designers, are not producing information in Revit, they will be dependent on others in the design team to input this information for them.
The BIM task group is in the process of consulting and firming up how the data drops in COBIE will fit into the various work stages. While the rest of industry does not have to follow its process, large projects are likely to do so because of the amount of effort that has been invested.
Lost in translation
So should lighting designers bite the bullet and somehow find the money for Revit (or equivalent programs, although Revit is the most widely used)? Probably not – because the problem is that Revit just does not work well for lighting.
Mark Ridler, chair of lighting at BDP, has seen the way BIM is being introduced across a multidisciplinary practice. Architects and structural engineers are having the easiest time, he says. “MEP engineers are finding it harder, but they are aided by good plug-ins. The problem for lighting designers is that there is not a plug-in that allows us to work in the way that we are used to working.”
The most popular lighting design packages, DIALux and Relux, are not compatible with Revit he says. The irony is that they work three dimensionally and embrace much of the thinking behind BIM, but are not able to work with it. Lighting Analysts, the provider of AGi32 – which, unlike the other popular programs is not free of charge – is trying to tackle the problem with the introduction of ElumTools, which it describes as “our new lighting solution for Autodesk Revit”. Colleagues of Ridler have been trialling it but there is, he says, still a long way to go.
Many manufacturers provide 3D data files for use within DIALux and Relux but, again, these cannot translate across into Revit. There is, however, work underway to tackle this problem (see box overleaf).
Different strokes
Another issue, says Ridler, concerns the way in which architectural models are built – these are usually unsuitable for lighting because they are not “light tight”. Initially, this may seem to be an issue that could be easily resolved but, given the number of specialist consultants with whom an architect will typically work and that each will have their own requirements – for example, some may concern themselves with airtightness while others are focused on acoustic accuracy – this may be too much to ask.
In any case, Level 2 BIM is about different team members working in different environments and being able to exchange information, so the need is for compatibility, not to work on a single model. As Ridler says: “What we need is an offline program that allows us to work in the way we are used to working.”
The way forward
The compatibility issues are grave but the need to deal with them effectively is so pressing, they are bound to be overcome. Peter Fordham at Morgan Sindall has experienced similar problems, but says: “I am sure that the simulation software will develop to work with the new modelling software and enable the seamless transfer of models in 3D in the same way that this has been possible in 2D for some time. This will lead to better integration of the lighting scheme within the rest of the design.” As Ruxton says: “People want lights in the 3D BIM model so they can do clash detection and so on, and to get drawings produced from the model.” This type of need is bound to drive compatible plug-ins. The lighting industry is right to be concerned about BIM, but it will be adopted. While an investment in Revit may well be costly and unnecessary, learning more about BIM will certainly not be time wasted.
Bridging the gap
Many manufacturers are aware there is a mismatch between BIM requirements and the information they are supplying. Eddie Taylor, outgoing joint chief executive of the Lighting Industry Association, says: “Lighting manufacturers will generally be aware of BIM and its requirements and, therefore, will be developing the key data of their products. Not all requirements are known yet and, therefore, the lighting manufacturing industry needs to be engaged in the process of ensuring requirements for lighting are well defined and well communicated.”
One group eager to help with this is the self-formed ‘template group’ that has grown from the Chartered Institute of Building Services Engineers’ and Landscape Institute’s BIM groups. Its aim is to produce product templates for all major elements, of which one is a luminaire. These templates would be a standard way for manufacturers to produce information in a spreadsheet that could then be provided at the various data drops within the Construction Operations Building Information Exchange (COBIE) process. Chaired by Richard Vincent at Hoare Lea, it has representation from Arup and the Building Services Research and Information Association and, on the lighting side, from lighting manufacturer Woodhouse and Mike Jankowski of Ikon Design. Woodhouse and other lighting manufacturers are working to refine the luminaire template.
