NTU Students at BIM Regional Hubs
Helen Beresford – Architectural Technology student at Nottingham Trent University
Following the BIM regional hubs focus, I was excited and enthusiastic about BIM. We were assured that it’s the future of building design, and that before long it was going to be commonplace and already mandatory on Government projects. I left the Crown Plaza inspired, tweeting Gary Ross (Capita Symonds) to thank him but, in all honesty, I was a little bit lost. Building Information Modelling sounds fantastic, and many companies swear by it, but what exactly is it?
I know what it’s not; “it’s not just 3D”, “It’s not just a new technological application” said Steve Race, the Regional Ambassador for BIM. A week later we moved from a very smart meet at the Crown Plaza to my own stomping ground; Nottingham Trent University. Again, we were greeted by Mukesh Kashyap, CIC EM Chair, who in turn introduced us to the very charismatic Howard Gill from Bite Design, and it was he that clarified what, who, when and why BIM was. Now admittedly I’m a little slow on the uptake, but for those like me who haven’t quite got their finger on it, this is what I’ve learned..
Unlike previous software such as AutoCAD, BIM Level 2, begins with a model. The end product is modelled, and from that the software extracts the plans, sections and elevations needed to construct the building. This guarantees coordination between all drawings, and improves buildability because the building has been digitally constructed first and the software has already checked for and highlighted any and all errors. As well as that, one change in the model will change all the drawings taken from it, because they are all interlinked. Gill sold BIM on three key points; unparalleled accuracy, increased productivity and stunning visualisations, and that’s exactly what you get. All the designer’s drawings will be connected and correct because BIM builds the building, and then draws it. And it doesn’t just apply to designers; manufacturers can get involved in BIM, importing their products into the model. All this connection between model, drawings, products etc prevents clashes, and an error checker within the program will highlight these clashes.
We’ve all used 2D programs to create plans, then a 3D program to create a model. BIM goes above these, into the fourth and fifth dimensions of information modelling; construction simulation and quantities. 4D programs like Navisworks products include a step by step animation of how and when each part of the construction will be built. This can be helpful in checking for conflictions, but also great in tendering so that contractors can explain visually to the client how their building will be put together. A real-time walkthrough makes complex 3D buildings much clearer and more attractive to all parties, and can be infinitely helpful with extension and renovations. BIM is able to clearly show an existing building, highlighting the areas for demolition, then calculating the areas left after demolition, before highlighting the new extension designs, as well as modelling the projected design. Surely a program like this could make self-builds and renovations much cheaper and simpler for the uneducated.
The fifth dimension includes quantities. The information we can get out of a BIM software improves exponentially the more information we put in. When starting off with BIM, about 65% of the input will be from the program, leaving only 35% of work for the office, and as time goes on and experience improves, your workload will decrease. If a building is fully modelled, programs like Vico software are able to deduce a full bill of quantities for the build and (as with the design drawings) this will adjust to any changes with the model accordingly and correctly. But quantities aren’t the only thing that can be calculated. BIM includes an Energy Assessment, and it links with the National Building Specification. It seems that we have one software to do almost everything.
BIM is also has a unique way of dealing with teamwork. Before, one huge DWG file would be sent to members of the project team, taking time and space. Changes made on one may not have been correctly transferred to the next making again more room for error. BIM creates a community for the team. All changes are colour coded according to the member that made the changes, and only the modified data is exchanged. This modified date is returned, updating the drawings.
The list of BIM’s fantastic qualities seems endless, but there are still some issues that need to be ironed out. There are contract issues; the JCT does not yet recognise BIM as an accepted program, and in the same manner, insurance prices go up because BIM is so new. Although prices have gone down, there is still a start-up cost, but you cannot charge the client a higher fee for using it. Although, with practice and experience, it is much faster to build using BIM than AutoCAD, it is highly recommended that your first few projects be small ones, because a loss will be made. Gary Ross told us “your first project will take a hit”, taking almost three times as long as it would have taken on AutoCAD. Training also takes time and money, and many employees may not be able to make the transition, resulting in staff losses. It’s also very difficult to predict who will be good BIM-ers as it takes different skills to those needed to use previous software.
The move into BIM isn’t an easy one, but with all the benefits it seems only logical, and it’s growing. In 5 years, all government funded projects will have to use BIM level 2 and it’s clear why. Its claims to unparalleled accuracy, increased productivity and stunning visualisations are founded and the 4D and 5D additions have fantastically useful potential. The next step is to try it for yourself, there are many different types of BIM software, and you’ll only know which is right for you, if any, is with a play around. And I do mean play! Each of the speakers ended their talks in the same way I’ll end this piece – by the way, it’s a pleasure to use!
You can see mine and my collegues article published on CIAT website: http://ciat.org.uk/en/bim/bim-focus-events/index.cfm