In the past we’ve been asked by Contractors and their subs to provide our cad files to them for use in generating shop drawings.
We typically allow this but require them to sign an indemnification form before sending them over.
We don’t see a problem with this but recently we’ve been asked by bidders, before the contract is even awarded, for our BIM models (Revit).
The concern with doing this is that the BIM models don’t necessarily include all the details and features of our design in the model itself since with Revit you develop the model only to a certain level of detail and then finish it off in the 2D drafting process.
So by giving them the model we are concerned that they will inadvertently depend solely on the model and miss things that are required in the actual contract documents. Apparently there are software products out there that do quantity take offs from the models.
Also, during bidding there is not a current set up contractual relationship between parties so that is concerning with respect to liability and the requirements on the bidders to follow due diligence.
Have you all experienced this type of request during bidding? What do you do about it?
I believe this depends on the situation. It is often understood that a model does not have all of the pertinent information and if not, a simple disclaimer can accompany the model.
From an estimator’s perspective, any information they can get will help. If you are able to provide a model that they can do major material takeoff’s from, this can save them a bunch of time (and possibility of mistakes/typos) that they can than use to estimate the more detailed information that is not in the model yet.
Hopefully if you do have a bidder depend solely on the model, causing them to miss things that aren’t in the model this will become very obvious when comparing to other bids.
The requirement to follow due diligence really comes from them needing to make money based on the bid submittals doesn’t it? If they miss information that was given to them and underbid the job it is ultimately on them to still perform the job at the bid price. To me, this type of request is typically done with the understanding that it is simply another tool to help them create a more accurate estimate, it is not used as the only means to create the estimate.
I am surprised by the responses of no .dwg (or other electronic type) files being given out. These are tools that the engineering and construction world can use to help reduce mistakes by removing the human factor of retyping information and copying and pasting and so on. Let’s use all the tools available to us to help reduce mistakes and reduce time spent recreating information to ultimately save the end client money both in time and cost of mistakes!
I tipically provide all .dwg files and BIM models (LOD300 Bricscad .dwg files) and I see no problem in that, as long that is understood that details are conveyed on the 2D plans.
Regarding proprietary issues, nothing I came up with is sufficently important to patent anyway… What is the contractor going to do? Copy my innovative and groundbreaking footing detail?
@JAE…I’m not a fan of providing changeable files to anyone…in fact, the engineering law in my state precludes it. If you provide pdf’s of the BIM set, at least you have some control over it. I’ve seen some pretty shady stuff done with files over the years by contractors, other engineers and owners. My vote is “NO”.
I don’t see an issue with providing revit and/or autocad files. If anything it makes my job easier come shop drawing review. The dimensions are typically better when I’ve supplied the contractor with a model as well as 2D details I crafted
I have used it to generate plans and sections for 3 or 4 small irregular RC and steel composite structure buildings up to 4 storeys. I have used it also to create the 3d models for piled foundations, embedded walls, micropiles and ground anchors as I do a lot of geotechnical work as well.
It was a time saver for the irregular buildings as the generation of sections would have taken me a lot of time manually.
I find it very easy to use as it’s just typical autocad+sketchup 3d modeling (push, pull, etc.) and then solid classification with the properties you want. Pretty basic stuff. It was very easy to integrate it in my workflow as it’s everything in dwg and the training was minimal. It’s only LOD300 but even that is much more than what my clients need.
I enclose a couple of pictures of partial ifc models generated by the software from real projects.
Looks great. I’m considering it for timber structures and hybrids between steel, timber and concrete. But I’m not sure if it would be better to use more timber oriented software.
Well, besides some timber beams and small walkways, I have never really done anything special in timber structures, so I 'm not qualified to voice my opinion on that. However, besides the obvious trial, you can use Bricscad Shape for free and that would give you an idea how the modeling process works and if it works for you.
When it comes to bids, we typically provide the drawings and takeoffs ourselves - one step further on our part, but helps ensure we get apples to apples bids we can compare.
