Tri City to Beta Test Server Technology

In an ongoing effort to advance our National CSUSA Alliance BIM capabilities on the job construction site, Tri City Mechanical is beta testing Riverbed’s Client Server compression technology.

To date managing CAD files out in the field has been cumbersome and very time consuming at best. One of the biggest challenges with BIM has been access the most up-to-date information on the construction job site. Keeping our AutoCAD fabrication database information available to our CAD detailer’s sitting in the job site trailer has been difficult.

The goal of this Riverbed beta test is to free up 2 man hours of CAD detailers “file management” time per day.

The ROI numbers…

Assuming we have 2 CAD detailers on site, that equals about 4 hours per day. Using numbers from the from a current project we’d save roughly $8,300.

Building Better BIM Models

3D Scanners for Retro/Renovation Work...
Our BIM Alliance is talking to 3D scanning companies about using their technology to build better BIM models of existing building conditions.
Here's a sample 3D scan showing a colored point cloud.

CSUSA BIM Alliance Signs CAD-Soft Agreement

March 31, 2010 - Our CSUSA National BIM Alliance has signed an agreement with CAD-Soft Consulting of Tempe, AZ to provide Comfort Systems USA additional discounts on all AutoDesk products. Please note: Only registered members have access to our CAD-Soft Autodesk price list.

BIM - A Contractor’s Perspective

6D Hyperlink BIM model of the Cancer Treatment Center of American, Goodyear, AZ

Building Information Modeling (BIM) is much more than simply a 3D CAD model. It's a process, driven by information-rich electronic data, enabling the entire project team to virtually construct and review a completed construction project with all of the sub-systems prior to the physical construction. We generally see BIM being used on larger projects because of the cost savings, and expect to see it being used on smaller projects in the future the same way CAD has become the industry workhorse.

When we hear about BIM these days, it's always 3D this, 4D that, 5D, and even 6D. What do all of these dimensions have to do with the virtual construction of a building? The 3D is obvious and relates to the traditional 3rd dimension or spatial aspect of CAD, the 4th dimension assigns time values (duration and start/stop) to components for construction phasing and scheduling. The 5th dimension assigns cost data to building elements for cost analysis or estimating, and the 6th dimension is for managing the operations of the facility (O&M). All of this informational data is being shared through the BIM tool, so you can start to see the big picture here.

Ultimately the advantage of using BIM results in higher quality work, greater speed and productivity, and lower costs. The emphasis here must be placed on mirroring the BIM model to the physical build: keeping both in sync is a must. Like any other construction process, BIM can have a negative impact if it isn’t properly applied.

The software environment: we use AutoCad as the foundation layer, with AutoCad MEP as a facilitator to creating trade-related objects. NavisWorks is then the application most effective for detecting interferences (“clashes”). Finally, we operate in a CAD-CAM (computer aided drawing-computer aided manufacturing) mode with a program called CAD-Duct which translates the sheet metal drawing objects into “machine language” instructions for cutting the metal (fabrication).

BIM P rogress: In 2004 we did what was then called “3-D coordination” on a large hospital. The required staffing was four mechanical detailers, one electrical, one fire protection, and a lot of correspondence with the structural steel fabricator. The role of the General Contractor was to preside once a week at a coordination meeting. The GC was, broadly, uninvolved in the process itself (although vi-tally interested in the outcome). The process of “clash detection” took about 8 months.

Fast forward to late 2008: another hospital, more complicated than the 2004 building, but a completely different team involvement. The General Contractor had their own technicians working on the structure and interior finish elements. The other trade elements (non-mechanical) had greater representation on the team. This was a deliberate and very detailed BIM-6 effort, added to the BIM-3 model created during the construction process. Because a more comprehensive team was involved, the model was completed in about 3 months. Best of all, the mechanical detailers didn’t have to draw tables and chairs!

We currently see the emergence of BIM departments and managers at the GC level, and they are aware of the need to begin this process much earlier. One recent project saw the GC BIM manager spending entire weeks in the architect’s office during the design process. As the construction teams become more sophisticated with the BIM tools and process, we think this pattern of early involvement will be the norm.

What’s next? On the horizon is “Integrated Project Delivery”, the formation of more tightly-integrated construction teams. (See the AIA website for a free IPD document.) BIM will be a major tool in this effort. All this will put additional pressure on the design community to adopt BIM. In the course of our BIM-6 project, we found that current control (BAS) software data bases are not compatible with AutoCad (or perhaps more precisely, they would re-quire a lot of translation). It would be nice to click on a BIM object, and get the temperature/flow/etc. The other major 6D “gap” is in maintenance software: these data bases also do not “talk” easily to the BIM model. This means that if you add a fan coil, you go to each of the three software packages and enter the data separately. Integrating these three information sources seems to be another development to watch.

And there are additional candidate functions for “D7” (BIM elements added to the current spectrum). One of the more interesting ones is a “work in progress” measurement where once the D4 (cost of elements) and D5 (time) data is included, the placement of these elements in the physical construction can be included. This allows a “real time” monitoring of completion and cost to date.

________________________________________

About the Authors

This article was written by Peter Menconi, P.E., and David Mettler at Tri-City Mechanical. Peter is also a Past President of the ASHRAE Central Arizona Chapter (1983 to1984).