Do rain-screen requirements for B.C. buildings make sense?
Nathan Edelson and his neighbours saved a ton of money when they retrofitted their Vancouver condo building a few years ago.
Edelson recalls that he could have shelled out four to six times the $35,000 he spent as his share had they accepted one retrofit plan that seemed to make some sense. But the total estimate was a staggering $5 million.
“It was a lot of money,” Edelson told the Georgia Straight in a phone interview.
The suggestion was to redo the Fairview condo’s building envelope according to a provision in the B.C. Building Code that requires two layers of protection with an air cavity in between called a rain screen.
A rain screen is a space rainwater and condensation that penetrate a building’s outer cladding can escape from, instead of seeping through to the inner framing, causing what’s known as the leaky-condo phenomenon.
The strata received another proposal to keep water away from the building without having to do a rain screen. It had a more affordable price tag of $1.2 million. The residents went with this one, and no one has complained about leaks since the renovation was completed. (According to the engineer consulted by the residents, retrofits such as this one that involve less than 60 percent of a building are exempt from the rain-screen provision.)
“People are satisfied with the work,” said Edelson, who was the strata’s president at the time the work was done.
The retrofit plan for the 66-unit building was developed by Uwe Naumann, a former BCIT building-envelope-technology instructor. The German-trained engineer has huge suspicions about the rain-screen requirement for residential buildings west of the Coast Mountains, adopted as part of the 2006 provincial building code.
“It’s the biggest fraudulent thing going on in British Columbia,” Naumann told the Straight in a phone interview.
Naumann, a consultant for housing co-ops and strata corporations, claimed that the rain-screen requirement benefits mostly engineering and construction companies, not homeowners. According to him, stopping water penetration is as easy as putting the right flashing or weatherproofing material on windows, doors, vents, and other openings, as was done with Edelson’s building. “That’s the simplest and most effective way to do it,” Naumann said. “And if people do it that way right, I tell them the building is good for as long as a whole building lasts.”
There’s also no substitute for good, old-fashioned design sense. “I always say the old architects, they knew it was raining in Vancouver,” he said. “The new architects, they don’t seem to think that it’s raining in Vancouver.”
The Homeowner Protection Office, a branch of B.C. Housing, licenses residential builders and building-envelope renovators. The agency also monitors the home-warranty insurance system provided by the private sector. Under the Homeowner Protection Act, builders and envelope renovators are required to provide a third-party warranty, which covers labour and materials for two years and water penetration for five years.
“That’s where the trick is,” Naumann said. “With a rain-screened wall, you don’t see that water ingress is taking place already within the five-year period. If on the sixth year you see the water ingress, well, you missed your warranty already.”
Naumann wonders why—if rain-screening is good—the government mandates only a five-year warranty on envelope integrity. “Why don’t you give them 50 years of warranty that there is no water ingress?” he asked rhetorically.
According to Naumann, a few “honest” engineers and contractors agree with his views.
The Burnaby-based Homeowner Protection Office punted the Straight’s request for an interview regarding rain screens to the Victoria-based Office of Housing and Construction Standards. However, the Ministry of Energy, Mines, and Natural Gas, which has jurisdiction over housing matters, did not make anyone available for an interview before deadline.
According to Naumann, it’s “absolutely ridiculous” that rain screens are required for buildings that are undergoing renovations even if they still have sound envelopes and have only a little water penetration around windows. That means a lot more money out of homeowners’ pockets, and, for Naumann, “That’s where the scam is.”