Fill it to the rim with BIM
September 1, 2009
You may have heard about building information modeling. But a lot of people are still uncertain just what BIM is - and isn’t. BIM is not software - it’s a software-using methodology that allows all trades involved in a building’s construction to see the project in three dimensions on their computer screens before ground is even broken at the worksite. It can eliminate the need to constantly produce new drawings throughout the process and ensure everybody is using the same information.
Details such as vendors, quantities and locations can be imbedded into programs. For sheet metal contractors, BIM means they can have access to detailed data that can be downloaded right to the fabrication machinery in their shops. That saves times - and money.
A lot of contractors are using BIM techniques, but some still aren’t sure what all the fuss is about. Snips decided to ask some contractors who are regular users of BIM on projects what they think of it.
Learning as they goJohn Saltsman, a computer-aided-design equipment operator at Southern Tier Custom Fabricators in Elmira, N.Y., is using BIM techniques for the first time on a Cornell University project. The use of building information modeling software was mandated in the construction specifications by the Ithaca, N.Y., school.
“The building is done in total 3-D,” Saltsman said.
So far, Saltsman said, he’s found it to be helpful. The company uses fabrication software from EastCoast CAD/CAM as part of the BIM process.
“It’s a tool, and it’s useful,” he said, adding that they’re learning more as they go through the project.
That’s not to say using it has always been smooth.
“Not everybody is up to speed,” Saltsman said. “Just like anything else with a computer, it’s as good as what you put in. You want to be sure you have all of the correct information before you start.”
The 3-D library of images that Southern Tier used did not have all of the HVAC components and products loaded in it, which meant Southern Tier had to create some of them itself.
But Saltsman is confident that the problem will work itself out.
“Manufacturers are going to get on board with us soon, I’m sure,” he said.
Time equals moneyFor Chris Miller, BIM is all about saving time and money.
“The bottom line is productivity,” he said.
Miller is the owner of Miller Sheetmetal in Bremerton, Wash. The company specializes in custom fabrication, architectural sheet metal, and heating and ventilation for commercial and industrial projects. Miller Sheetmetal also provides ventilation and odor-control services to wastewater treatment plants.
Miller said BIM is used for “everything and anything” at his company.
It first started using its current form of building information modeling about four years ago. The shop uses Shop Data Systems QuickDuct CAD that downloads directly to the SDS CAM Program, a combination of Shop Data Systems programs, when performing BIM.
The first year of using BIM methods paid for the initial investment in the software, he said.
The company has also enjoyed a 30 percent increase in draw time, a 6 percent savings in the field and a 4 percent shop savings under BIM methods.
Besides such financial savings, Miller said that collaboration with other trades is much smoother than in the past. He has also enjoyed the benefit of sending orders directly to suppliers and distributors.
Miller said the program he uses allows him to download purchase orders and e-mail them to a supplier if he needs spiral duct or grilles and registers.
For Miller Sheetmetal, BIM has been most useful on hospital and medical facility projects, where systems and piping can be more complex.
The cure for some projectsOther companies agree with Miller’s assessment. Alan Van Mun, coordination draftsman for Tweet-Garot Mechanical Inc. in Green Bay, Wis., knows exactly how BIM can help on hospital projects.
In 2007, Tweet-Garot installed the mechanical systems for the Froedtert Cancer Pavillion in Waukesha, Wis. The contractor is currently working on a new tower being constructed at the Appleton Medical Center in Appleton, Wis.
BIM has helped Tweet-Garot to navigate its plans around the medical gas piping and other systems that are usually placed in hospital ceilings.
“The reason it is beneficial the most (for hospitals) is the amount of medical equipment and different systems” they contain, Van Mun said.
While it is difficult for Van Mun to give an exact number on how much money BIM has helped save the company, he said the benefits are definitely felt. Tweet-Garot has used fabrication software with BIM for the past five years, and it has drastically cut down on errors.
Van Mun uses QuickPen software for all of the ductwork, which is then run through Navisworks to make sure it doesn’t clash with other mechanical systems.
This has been a major benefit when it comes to coordination with other trades and project architects.
“As architects adjust designs, engineers don’t always catch it,” he said.
Before using BIM, Van Mun recalled one project where the architect made changes to the ceiling designs, which is where the mechanical systems were originally to be installed.
“We had to move all of the equipment down to the basement,” Van Mun said.
But now BIM has created better coordination between Tweet-Garot and its architects and subcontractors.
Van Mun said that BIM have made some project designs as easy as “putting a puzzle” together.
Collision preventionOfficials at the P1 Group Inc., a full mechanical, electrical and plumbing contractor in Lenexa, Kan., are also big users - and big fans - of building information modeling.
“We’re using it on all of our major projects,” said Elizabeth Goble-Barner, a detailing manager at P1 Group, adding that the company has used BIM regularly for about five years.
The company uses QuickPen products with its BIM projects.
For Goble-Barner, one of the biggest benefits of BIM comes from “collision checking,” which is ensuring that electrical, piping, ductwork and other systems do not run into other trades’ work or each other.
“It dramatically increases our productivity in the field - both for sheet metal and on piping,” she said.
On a recent hospital project, for example, the general contractor P1 Group worked with used the BIM method to coordinate all the trades. Without having to wait or worry about obstacles both physical and work-related, P1 Group workers were able to install piping and ductwork in much less time.
“We were finished hanging pipe on every floor before other trades were even in,” Goble-Barner said. “Normally, we’re battling the walls.”
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