It is important to be aware of new developments in potential radon gas exposure as some municipalities consider adopting the Step Code and tightening homes through their bylaws. Very energy efficient homes tend to draw in more radon gas. According to Health Canada, radon gas is responsible for 16 per cent of lung cancers in Canada.
Radon gas is the result of decaying uranium finding its way into homes through cracks in foundation walls and floor slabs, joints, service pipe gaps, floor drains, etc. Simon Fraser University is doing leading research into radon in BC, identifying potentially high risk areas previously thought to be low risk.
The BC government recently identified additional high risk regions requiring venting pipe systems. It is interesting to note the government reports Jordan River requires mandatory venting but Sooke and Port Renfrew do not. Duncan requires venting but Victoria and Nanaimo do not. Health Canada reports some homes in Greater Victoria have also tested for unsafe levels of radon. In a recent news story, an SFU scientist says “there hasn’t been enough testing to fully understand the risks” in many communities. “Even in areas where the threat was thought to be relatively low, more extensive testing has revealed higher levels of radon than expected.”
The BC government does not categorize Vancouver’s North Shore as requiring radon venting, however radon testing companies have discovered high levels of radon in that region. Some of these municipalities have adopted Tier 3 of the Step Code. Without radon venting, this has been described as a “perfect storm” for radon exposure. More investigation is needed to clear up these risk inconsistencies, especially in light of ongoing changes to the radon map.
In the interests of consumer protection, we continue to recommend municipalities avoid the Step Code and wait for the energy efficiency review presently underway by the National Building Code committee that has included radon mitigation as a key consideration.
We support health and safety as prime building code considerations in housing under which other attributes such as increased energy efficiency can be achieved with attention to diligence, consumer protection and affordability.
Also Canadian Contractor magazine
Mike Holmes: “There’s this idea that because there’s no basement, a slab-on-grade home eliminates the risk of radon gas seeping into a home. All homes, no matter their construction, can have dangerous levels of radon gas. Radon gas can seep in through foundation cracks, exhaust pipes and even well water. There’s no indication as to whether or not your home contains dangerous levels of radon without testing for it.” Read https://nationalpost.com/life/homes/mike-holmes-slab-on-grade-an-economic-green-minded-option-for-foundation
Here is a recent update:
- The BC govt doesn’t know where the radon is – the map keeps changing. In the new code, Duncan is now high risk for radon. The BC govt maintains the North Shore is Vancouver is low risk but an SFU scientist testing for radon says that is wrong.
- Heath Canada’s maximum radon exposure is 200 becquerels per cubic meter. The maximum recommended exposure by the World Health Organization is 100 becquerels.
- A recent study revealed newer homes, built within the past 25 years, have 31.5% higher radon, on average, compared to older properties. Part of the reason is radon is more prevalent in larger, energy efficient homes.
- The good news is radon can be easily mitigated with sub-slab depressurization using a venting pipe and fan.
The lesson is that customers depend on builders to do our diligence, stay up to date on the latest information through seminars like this, and don’t depend solely on govt getting it right. Remember, the govt gave us leaky condo, asbestos insulation and & urea formaldehyde. That track record is not going to change as long as they pursue energy efficiency above health and safety.