Building Design

BIM and Sustainable Design, Part 1

21 Jun, 2007 By: Heather Livingston

A look at how the two are coming together (or not) in practice.

As building information modeling (BIM) matures into the promise of its potential of easing interoperability, saving time, and reducing mistakes, so, too, does sustainable design grow in popularity, sophistication, and importance. To get a feel for how the two are coming together in practice, I asked Renee Cheng, AIA, head of the School of Architecture at the University of Minnesota to elaborate on the issue. Cheng recently served as a juror for the AIA 2006 BIM Technology in Architectural Practice (TAP) Awards and is currently serving on the AIA Board Knowledge Committee. Next month, I’ll explore the practical differences between sustainable design platforms as offered by Bentley, Autodesk, and Graphisoft.

HL: How are BIM and sustainable design working together?

RC: Well, there are things that they could be doing and things they are doing, and there’s a big difference right now. It’s probably one of the most frustrating gaps in the potential for what BIM can do. I think that many of us are looking to sustainable design as a natural fit because of the possibility of inventorying data using measurable outcomes for lifecycle costs or building energy performance. There are people working really hard to get good work out there, but it’s been slow.

HL: Do you think that BIM and sustainability currently is a complementary relationship?

RC: I think that it’s a natural fit that the two would go together. [There have been] a lot of issues with BIM such as interoperability, regulation and compliance, and software that’s been slow to respond to user needs. A lot of the same problems with general BIM issues are being experienced by people trying to do sustainability within the BIM environment. So, yes, they’re a natural fit together and are in theory highly complementary. In practice, they’re running up against the same problems everyone else is having.

HL: How are BIM programs supporting sustainable design?

RC: I think they’re all taking it seriously and are investing in it in their own ways. I wish the big three would try to deal with interoperability with programs like Ecotect. I think Graphisoft is doing the best with that. It would be great if the others would do more. Here at University of Minnesota, we’re very Revit oriented because there are so many firms in our region using Revit. For our purposes in school, if SketchUp, Revit, and Ecotect could all talk together we’d be much happier than we are now. Ecotect has been popular with our faculty and students because it’s closest to the kind of intuitive tool that people want as designers and teachers, but students are having to rebuild their models in Ecotect instead of being able to import them, and then they have to manually transfer that information back.

I think the more communication that can happen on this issue, the better. There are a lot of urgent issues surrounding BIM, but this is one of the most urgent because of the 2010 Imperative and 2030 Challenge and the pursuit of the carbon neutral building. There’s so much data and research involved in achieving any of those goals and clearly BIM would be a way that we could track and predict for design. That is extremely data heavy, and that’s where we need the capacity of the building information models.

HL: Are the programs presently supplying that capability?

RC: There definitely is not a transparent and easy way to do it. There are people who are trying to do it and having success in certain areas, but the need is clear and a number of firms and software companies are pursuing that. I’m seeing a lot of manual translation of things. We’re in the early stages where the tools aren’t exactly transparent, but the possibility is huge and the need is urgent.

HL: Is it better to have the sustainable design platform built into the BIM program, or for it to be a complementary program?

RC: I don’t know. To make it smooth to move between them would seem to argue to within. However it’s hard for one program to do everything. For some practitioners, having it built in is fine and that’s mainly what they need, but for other people trying to get to more complex buildings or in very specialized situations, there are reasons that they would want to break it off or use something different. Then, too, people just have their personal preferences of interface with what they like. Ideally, I think it’d be both embedded and interoperable because there are some people who are more advanced who like to tweak the script and know what they want, and there are other people that just want the basic general analysis.

HL: How can the architect, contractor, and engineer work interoperably when they all use different platforms?

RC: And they never agree on the one that works best for everyone, so philosophically one could argue that everyone should work with the software they’re most comfortable with and the most important thing is that the database remains consistent and consistently readable. The other side of it is to say there needs to be a mega-program that does everything and tries to anticipate what everyone is going to need and make it very easy to move within and where you don’t even notice that you’re moving to a different program. You’re just using a different set of tools within the same program. They’re both viable options, but I really don’t know what’s best. We’re in such early stages right now that we have a little bit of everything going on, but the problem is the mega-program is not ideal and the add-on programs are not talking to each other that well, so it’s a bit of a mess.

HL: What other products hold promise for sustainable design?

RC: There are tools that are starting to become really helpful. Our Center for Sustainable Building Research on the website for the college of design at the University of Minnesota has a nice interactive tool for window orientation and overhang, and it gives you some basic R values and quick calculations to offset things like window sizes change or mullion depth. Small things like that begin to help the designers and generally build up the awareness of the energy usage.

Then you’ve got people like John Fernandez at MIT who’s mapping materials based on their carbon footprint. That gets much more complex because he’s even trying to take into account things like the political climate and social issues of how much the wages are in China to mine copper versus in America and the pollution in processing, so that gets at the much more complicated picture of the footprint of materials. There also is GreenBlue, a spinoff of McDonough Braungart Design Chemistry, and they’re trying to rate products based on energy and carbon factors, much like you would with Energy Star appliances to make it easier for consumers, except they’re going to do it for pieces of things, not the whole design.

HL: Architecture is typically a pretty slow moving industry, but in the past couple of years, green design has shot off. Do you think that BIM has quickened the pace of that?

RC: There has definitely been a really nice augmentation of the two trajectories, where they both have had quite a bit of momentum in the past couple of years and we’re starting to see them intersect. I’m looking forward to what’s going to happen in the next few years. It’s such a natural fit between the building information model that can deal with data and the sustainability effort which is largely based in measurable outcomes, whether they be immediate, longer term, or more complex where they stretch to deal with other issues that lead to carbon footprint and the way things are produced and broken down, so there are different scales that could be addressed. To do well in sustainable design, you need data and you need to be able to visualize it, and BIM offers that possibility.

HL: Where do you see green design and BIM in five years?

RC: Five years from now, I hope to see a lot more tools that are [better] able to talk to each other and that deal with the range of issues from minimizing waste to energy calculation to lifecycle cost.

HL: Ten?

RC: In 10 years, I hope that some of the metrics begin to evolve beyond compliance minimum. I consider LEED to be very successful in terms of the consumer end of it, but very simplistic in terms of really dealing with sustainability. I think it’s great that it raised everyone’s awareness and put a metric on to buildings, but in ten years we could really see a range of metrics that are a lot more sophisticated and that deal with the construction systems, the waste, the lifecycle costs—a lot more factors and that those could be manipulated by the designers because of the tools they have.

AutoCAD Tips!

Lynn Allen

Autodesk Technical Evangelist Lynn Allen guides you through a different AutoCAD feature in every edition of her popular "Circles and Lines" tutorial series. For even more AutoCAD how-to, check out Lynn's quick tips in the Cadalyst Video Gallery. Subscribe to Cadalyst's free Tips & Tools Weekly e-newsletter and we'll notify you every time a new video tip is published. All exclusively from Cadalyst!
Follow Lynn on Twitter Follow Lynn on Twitter

Which file format do you use most often for CAD drawing/model exchange?
Native format
Submit Vote