A survey of 5,500 house owners in BC, Ontario and Alberta has found that 15% of them are illegal.

The poll by insurance firm Square One also revealed that 11% of all home owners surveyed rent out part of their home with 14% in Alberta, 13% in British Columbia and 9% in Ontario.

"We wanted to conduct this survey for two reasons," says Daniel Mirkovic, Square One's President. "We're noticing an increase in inquiries by house owners that are renting a portion of their home to non-family members. We wanted to understand what was driving this increase. We also wanted to understand how house owners are coping with municipal laws relating to rental suites in single-family homes."

Extra income was the main reason for renting out part of the home (40%) followed by helping with the mortgage (34%) and for companionship (13%).

Square One's survey found that 17% of rental suites in detached houses are considered illegal with the highest percentage in Ontario (21%) followed by British Columbia at 15%, and Alberta at 14%.

"Most municipal regulations for secondary suites ensure residents have adequate and safe housing options," states Mirkovic. "But some, like the one rental suite per single-family house, are just outdated. It's hard to understand why cities advocating for more affordable housing options would continue to enforce this outdated regulation."

Are you looking to invest in property? If you like, we can get one of our mortgage experts to tell you exactly how much you can afford to borrow, which is the best mortgage for you or how much they could save you right now if you have an existing mortgage. Click here to get help choosing the best mortgage rate

More market watch: