What type of building material snaps together like Legos, strongly resists fire and seismic activity, is environmentally friendly and has made its way to Helena?
Made by gluing together perpendicular layers of wood, CLT has gained significant traction in the construction world over the past few years. And its viability is demonstrated in two Helena construction projects.
Both the Helena Regional Airport and Bjerke Architects have used the product in recent construction projects, which has caused some excitement among construction and architectural firms.
CLT is a relatively new product made from viable low-density hardwood species that have traditionally not been usable as construction-grade materials. The product is very highly rated for being fire-retardant, quick to construct and resistant to seismic activity.
The material is replacing steel in some projects but also is regularly reinforced by steel.
One might expect CLT to be costly, but according to Kory Kennaugh, architect at CWG Architects, it's actually less expensive than the original steel-based design at the airport.
Helena Regional Airport chose CLT for the ceiling in the new passenger boarding area, which is part of a larger project that will see the airport expand to host 500 more passengers.
Airport Director Jeff Wadekamper said the airport authority board wanted a lot of wood in the design to match the existing decor.
"We looked at a few different options for the structure," Kennaugh said. However, the original steel-based design needed a finish and would have required at least three different materials.
Dick Anderson Construction, the company building the airport addition, recommended CLT as a possible alternative, Kennaugh said.
"When we looked at CLT, it fit all of the needs," he said.
Tim Tholt, project manager at Dick Anderson, said the crew has had a very positive experience with the product. This was their first time working with CLT, and he called the installation "fast and easy."
According to Tholt, the CLT ceiling saved the crew three to four weeks of construction time over the original steel design.
"It took us about a day and a half to install it," he said.
Wadekamper said the airport is excited to be using CLT. He bragged that the product is environmentally friendly while maintaining a "rustic Montana aesthetic."
Kennaugh said this was the first time CWG Architects has worked with the product, which was very exciting for the firm.
Representatives at Dick Anderson say they are starting to see the product pop up more and more. The company will use CLT in another job in Wyoming.
Bjerke Architects used CLT for an outdoor elevator at a commercial building at 2905 N. Montana Ave. Designed by Tracy Egeline, an architect at the firm, the elevator is aesthetically pleasing as well as practical.
The project was an effort to make the top floor of the building more accessible. The lift and shaft of the elevator are made from CLT while being supported by steel.
The structural panels of the elevator were anchored into the ground with steel hooks.
"I'm always excited to work with a new building material," said Diamond Construction's Nate Pierce, just prior to starting work on the project.
Pierce said he believes the product will become more and more viable as the public's awareness of it increases. He said Diamond may use the product more often, when applicable, in the future.
"It is exciting as architects to push the limits and try new things," Egeline said.
CLT isn't limited to niche uses. The product can be used to create timber-framed houses. In Portland, Oregon, there are plans for a project to build a 12-story building out of CLT.