Time for mass timber and prefab? B.C. eyes changes to 'bias' in building code
Materials and methods for building housing have hardly changed in a century in British Columbia and the provincial government is now looking at ways to bring housing online faster and more sustainably.
Prefabrication and mass timber construction make up only a small portion of the housing built in the province and the housing minister sees regulations ripe for change to make them a more attractive option for builders.
“It means you can get projects done at double the speed and actually way more sustainable than using traditional methods,” said Ravi Kahlon of pre-fab construction.
“We (also) need to look at the building code to find ways to make the ability to use mass timber in housing much more smooth. We know there’s a bias against mass timber in the building code.”
In B.C., houses and townhomes are essentially built from scratch on-site, but in much of the world panels are pre-fabricated more efficiently in warehouses and assembled on-site.
“We save approximately two months off the construction schedule compared to a traditionally-built on site,” said Norman Morrison, founder of Ajia Custom Pre-Fab Homes, one of the few companies offering that model of homebuilding.
“We use panelized structural framing because that still allows us to be completely custom, we can literally build any size, shape or style.”
LOTS OF TALK, LITTLE MOVEMENT ON MASS TIMBER
Pre-fab construction is also how mass timber projects are built, but the technology isn’t widely used for a number of reasons, even though the current building code allows projects of up to 12 storeys.
“It’s a chicken and egg situation,” said Brad Doff, with SFU’s Renewable Cities Program, explaining that because it’s not widely used, there’s not a lot of wood fibre for the panels, and there’s not much produced because it’s not widely used. https://www.renewablecities.ca/
Mass timber construction involves taking smaller pieces of lumber, engineering them together with bonding agents. This makes them so strong they can replace concrete and steel but with a dramatically reduced carbon footprint and faster assembly; many of the panels are pre-fabricated off-site.
“There are a number of barriers to this relatively new technology and building type. Some of them are at the regulatory level,” said Doff, who is encouraged that Kahlon is enthusiastic about the technology and reducing hurdles.
“We're not going to see the uptake of mass timber or prefabrication if the system's going to slow us down and developers aren't going to save the money to get occupants in there earlier because that’s where we see a lot of cost savings.”
DESIRE FOR INNOVATION, BUT BARRIERS REMAIN
Six-storey wood-frame structures are common in B.C., but there are only a handful that are taller, even though the technology is proven. UBC’s Brock Commons is 18 storeys tall but remains an outlier.
“It really is, I think, an opportunity for us, as we go forward. We already have in BC more mass timber buildings than all of North America combined, so we are leading the way,” said Kahlon.
“Not only can we support forestry in British Columbia, we can support innovation but at the same time ensure that our buildings are sustainable. There’s not many products that allow you to do all those things.”
So all eyes are now on his government to see if they’ll follow through with their commitments to modernize the process, invest in non-market housing, and let industry move as fast as it’s able, rather than as fast as red tape will allow.x
“We’re talking about a big paradigm shift,” observed Doff. “We've seen other industries -- agriculture and retail -- just explode in productivity, 1500 per cent over the last 75 years and construction is just a couple percent each year over that same time span.”
Courtesy of CTV News.