Adopting BIM is a difficult and often unrewarding task. As the BIM Manager you are expected to have all the answers to all the questions anyone may ever throw at you. It can be very intimidating being thrown into a high-level meeting and being expected to explain the principles to principals in suits and ties. It’s not quite the same as arguing the case with all your Twitter followers is it? Well, fear not, my avid readers, for I have outlined the 5 most important BIM questions you could be asked below. The next time you are called over to the project architect’s desk to explain how he should answer a letter from the client, or are heckled by some clever know-it-all at the end of your presentation, refer back to these answers. Everything stated is total, irrefutable fact, and anyone who says any different is welcome to their incorrect, uneducated and frankly idiotic ideas. But not on my blog.
BIM means modelling a Building Information Modelling model. It is the process whereby a building is modelled and turned into drawings at the click of a couple of buttons. They must be intelligent drawings to be defined as BIM, which means they can’t have any spelling mistakes or misuse of grammar, and must be able to be built without actually being printed on paper. This is why you hear so much talk of “the Cloud” and “mobile devices” when referring to BIM. The first step to successful BIM modelling is to buy an iPhone and download the Cloud.
BIM can’t be 2D, and to be 3D alone without clash detection or construction sequencing is called “Closed BIM”. “Closed BIM” means that you can’t open your model in “Open BIM”. “Open BIM” is what people on the leading edge are aspiring to and solves all your problems. Only “Open BIM” models can be opened in “Open BIM” by converting them to “IFC” (Ipswich Football Club). IFC strips the “Open BIM” model of all geometry and other unnecessary overheads, allowing it to be imported into a “Closed BIM” application, eradicating the need for “Open BIM” and allowing you to communicate with everyone everywhere.
Purely financially, it’s the client. You’ll be expected to do extra work at a much earlier stage than you would have traditionally at a much lower fee. Not only that, but you will be required to perform coordination duties which you could have happily ignored when working with CAD. “We’ll sort that out when it gets to site” is tantamount to having Tourette’s in the BIM world.
Don’t think you’re going to do anything more efficiently with BIM; you’ll waste every penny you save on frivolities, like additional staff (to input all the non-graphical properties you would have previously left to the specification), overtime (which you’ll spend tweaking your line thicknesses and shades of grey to get that exactly perfect visual work of art you’ve come to expect from your CAD drawings) and beautifully modelled, highly detailed lift (elevator) cars & control panels or brise soliel connection details. BIM is based on a 3D model and therefore requires everything to be modelled as an exact copy of the final manufactured building component. It requires an extra level of input you may previously not have needed. You’ll no longer be able to “represent” simple building components such as a door with a single rectangle, you’ll need to model the frame correctly, every hinge, the handles and other hardware, so that everything is visually perfect. If it doesn’t look right graphically, it can’t be constructed, and therefore isn’t BIM.
The most benefits are gained when companies realise that the BIM acronym stands for “Building Information Model”, not “Models”. Those that can adopt the production of every discipline within a single model will be ahead of the game, delivering true, economically efficient BIM and seeing immediate benefits. That’s why all the leading-edge companies have started to retrain their staff – the quicker your architects can become qualified in structural engineering, the more benefit you’ll gain from BIM.
This question usually comes from the senior directors, CEOs or Senior Assistant Associate Vice Presidents of companies that are using ArchiCAD or AECOsim Building Designer or some other “little bim” software. What they actually mean is, “Why aren’t we using Revit?” and it is the easiest one of these questions to answer. You can answer this by proposing that you swap the whole practice over to Revit. Mostly you don’t even need to fill out painful documents like strategies and budgets. Mention that your closest competitors have all migrated to Revit and within a short space of time you’ll be promoted and your bosses will be able to smile smugly over their 5-iron and confidently state “We do BIM. What do you think about them apples?”
One side note: the question is irrelevant if asked within a civil engineering practice. You cannot do BIM if you are a civil engineer, as civil engineers don’t build buildings. They build roads and dams and railway lines, stuff like that. None of which are buildings. And neither are their products classified in Uniclass, so it’s impossible to add into a BIM model even if they wanted to.
This is a complex legal question which has to be carefully addressed in project contracts, title deeds and guaranteed premium bonds. With each discipline modelling portions of the project, it is critical that ownership is clearly, and legally, defined on every object. It is best to involve your company solicitors at the earliest stage possible, certainly before you start modelling, as failure to do so could result in loss of fees or even prison time for breach of contract. This is the main reason why the prime objective should be to model everything yourself in a single model (see Question 2).
Think of object ownership like a fridge in a shared house: it’s imperative that you stick a piece of paper with your name on it to your left-over chicken, milk, and chocolate, otherwise one day when you really fancy some of it, it will no longer be there. And then what will you do when your girlfriend (or boyfriend) comes round expecting a big slab of Dairy Milk and all you’ve got is half a cold sausage?
Adding an attribute or parameter to infer ownership is not legally sufficient as it cannot be seen in all renditions of the BIM. PAS1193:2-2016 (not yet published) requires you to clearly state the ownership of each object visually on every instance. Further than that, it recommends an “express note of ownership” on each drawing the object appears on. It can make your drawings fairly cramped, but using a small stick font will overcome those concerns.
Never, ever, copy someone else’s object or even draw a representation of one. I understand the need to produce your own contract deliverables, but believe me, the risk is too great. I know of one architectural practice who modelled a steel column for a client meeting and were successfully deported for “impersonating a structural engineer without a structural engineering qualification”. In the US, to legally copy another discipline’s object you need to fill in a BxP (BIM eXchange Proposition) prior to opening the email with the other person’s model attached to indemnify you against “an otherwise unforeseen change of thought due to the suggestive nature of an unfamiliar design concept”.
To be safe, always leave an empty space at least 300mm clear of another discipline’s object.
This is a question we are asked time and time again, usually by the same people. If you’ve not started down the BIM road yet (bad analogy I know, as BIM and road design are mutually exclusive), you’re probably too late. Every project in the UK has to be 100% BIM by the 13th January 2016, and with such a steep learning curve there is, I’m afraid to say, no way you can hit that deadline now.
For the benefit of any deluded practices out there though, I’ll sign off with my “10 Steps To An Assured BIM Delivery”. Follow these golden rules and your BIM endeavours cannot fail:
- What is BIM?
- Who will gain the most benefit from BIM?
- Why aren’t we doing BIM?
- Who owns the model?
- How do I get started with BIM?
- Buy Revit
- Buy PAS1192-2:2013
- Send all your staff on a 5 day training course
- Wait for a client to demand BIM on a project
- Check the contract with your legal team
- Send all your staff on another 5 day training course as they would have forgotten what they learnt on the first one by now
- Model as much detail as you can
- Add every property that you can to every object
- Read PAS1192-2:2013
- Issue your data in COBie format
Photo by Caleb Woods on Unsplash