December 1, 2015 by Canadian Underwriter
The Institute for Catastrophic Loss Reduction (ICLR) met Monday’s deadline to make submissions for the next iteration of the Ontario Building Code. The Institute opted to submit two proposed code changes: to make backwater valves and hurricane straps mandatory in all new builds in Ontario.
Currently, the Ontario Building Code allows for the installation of backwater valves (i.e. devices that are placed in sewer laterals that help to prevent water from backing up from the municipal sewer into the basement) “where a building drain or a branch may be subject to backflow.” However, there is ample evidence that almost any home connected to a public sanitary sewer system “may” be subject to backflow. The current wording of the code makes this unclear – as a result, new homes in most Ontario municipalities are not being built with appropriate sewer backflow protection. ICLR’s suggested wording of the relevant section of the code would see deletion of this problematic phrase.
ICLR research has shown that despite consistent application of code wordings related to backwater valves across Canada, there are differing interpretations of code wordings, which have resulted in differing reported frequencies of installation of backwater valves. Thus, the Institute has recommended in its research – and in this code submission – that sentences in the National Plumbing Code and provincial building and/or plumbing codes that relate to installation of backwater valves be reworded or clarified to ensure they are clearly and consistently interpreted and applied. Deletion of the “may be subject to” wording is part of this recommendation.
In its submission on backwater valves, ICLR also argues several additional reasons why backwater valves should be mandatory in all new builds in Ontario, including the health impacts of having raw sewage in homes following sewer backup events, increasing damage claims to insurers and municipalities from sewer backup, the expected growth of sewer backup claims going forward, and the known effectiveness of backwater valves in reducing the risk of sewer backup.
ICLR’s submission to mandate the use of hurricane straps is intended to reduce damage caused by uplift forces exerted on roofs during extreme wind events. The current Ontario Building Code requires that roof joists be toe-nailed into the upper plate of walls using a minimum of three nails. That requirement (i.e. essentially to largely use gravity to keep a roof down) is adequate in the absence of extreme wind, but does little to keep a roof in place against the upward force that is caused by pressurization of a structure during a wind event. What’s more, work in the field by Western University’s Storm Damage Assessment Team at the site of the Angus tornado in June 2014 found noncompliance in many roof to wall connections (i.e. one nail or no nails where the code prescribes three).
Along with their superior performance over toe-nails, an additional benefit of using hurricane straps is that building inspectors do not have to go up on a ladder to see if straps have been installed (they are visible from the ground). What’s more, the addition of hurricane straps adds virtually no cost to the construction of a new home (ICLR estimates that installing straps on an average new home would cost approximately $150, parts and labour included. Additionally, they would replace the need to toe-nail roof/wall connections, meaning the labour that goes toward that could be put into installing the straps).
ICLR’s recent code submissions will mark the end of the beginning of a long review process.
This effort marks the second time that ICLR has made code change submissions in the province of Ontario. The Institute, on behalf of Canadian property and casualty insurers, made three submissions to the last Ontario building code process and had one accepted. The accepted change, added to section 188.8.131.52 of the code, increased the number of nails in plywood roof sheathing on new homes from a 6×12 (inches) pattern to a 6×6 (inches) pattern.