At the end of a quiet cul-de-sac near McMaster University, a nondescript tan house sits on the edge of a ravine.

It's zoned as a single-family home. But it has 12 bedrooms. Inside, a long, white hallway holds bedroom door after bedroom door, identified by gold numbers, each with its own lock.

Rent for a bedroom in the shared house, popular with Chinese students, runs $500 a month or more — bringing in upwards of $60,000 annually for the landlord.

We know that there's a huge problem of unsafe, over-packed student houses. - Aidan Johnson, city councillor , Hamilton Ward 1

There are seven ground-floor bedrooms and five bedrooms in the basement.

Even though the city knows the home has 12 bedrooms —thanks to a 2016 complaint — there is no active enforcement underway.

There are no safety inspections, no fire inspections, and it's not clear from city records whether all of the renovations have been approved by building inspectors.

The file on the 2016 zoning infraction was closed after inspectors showed up in July, a time when all the students had gone home, and found no one living there. The house wasn't flagged for follow-up and the inspectors didn't tell the fire department about the home.

The city hasn't gone back since new owners took over and began renting out the bedrooms again.

The stakes are high

At a time when developers and landlords see multiplying dollar signs on every piece of property they can sell or rent out, the story is symptomatic of a rental market where tenants, under pressure to find affordable spaces, can be vulnerable in Hamilton.

Inside the house, the main floor holds seven individually locked bedrooms. (Kelly Bennett/CBC)

And it raises questions about the city's ability to adequately police that market — and to ensure housing is safe, inspected and approved.

Among those questions:

How effective is an approach where city inspectors only respond to complaints and close a file unless another complaint comes in?

Are city departments effectively working together to keep tenants safe?

How aggressive and committed are city bylaw enforcers?

Are the current laws adequate to keep tenants safe?

The stakes are high: A fire killed three people last summer in a Hamilton house that would have been subject to yearly fire inspections if it had been zoned properly and licensed as a lodging home.

The fire department doesn't have a file for this home. It has never inspected to see if there are sufficient smoke alarms, or if they're working.

The current owner told CBC News he believes he's offering a solution to McMaster's housing shortage.

"Without those landlords providing all these students residences, the university will run into chaos," said the owner, Joseph Guo.

A fire killed three people last summer in a Hamilton house that would have been subject to yearly fire inspections if it had been zoned properly and licensed as a lodging home. (Dave Beatty/CBC)

It's unclear how many, if any, of the bedrooms were permitted — and inspected. The previous owner got a building permit in April 2015 to "renovate the basement and add laundry room to the first floor". The city has no other building permits on file for the house in the last 18 years.

The house felt bad to live in, and overcrowded, two people who lived there last year said. A current tenant said the doors are thin and the house can get noisy.

'A broad, systemic problem'

Coun. Aidan Johnson represents the ward that contains McMaster and said the overcrowding in houses is "a broad, systemic problem."

The house is a 15-minute walk from McMaster University. (CBC)

He said low-income students, new Canadians and those learning English are more likely to be exploited.

"We know there are other houses like this. We know that there's a huge problem of unsafe, over-packed student houses in Westdale and Ainslie Wood," Johnson said.

"And it's bad for student tenants, and bad for everybody. It's only good for the bad landlords."

'We don't know the … law there'

Junjie Piao is a master's student at McMaster University. While he was still living in China, he found the house advertised in Chinese on a website for the McMaster University Chinese Students and Scholars Association.

Junjie Piao lived in the house for four months before moving out, saying it was "overcrowded." (Junjie Piao) Piao said he thought it was better to rent from a Chinese landlord so that he could negotiate and get the information about the rental in a language he could understand. He moved in for the start of the fall semester in 2015.

But Piao said Goerge Huisong Yuan, the former landlord, charged him a year's worth of rent upfront — about $6,600 — and refused to refund him when Piao wanted to move out in December. In Ontario, landlords cannot require more than a month's rent as a deposit.

"Before I moved in, he told us it is the rule in the Hamilton area, and most of us are first-year (students), so we don't know the rule or the law there, so we just do what he says," he said.

Previous tenant Junjie Piao said he rented a room in the house after seeing this ad in Chinese for a five-bedroom house near McMaster. CBC has blurred the contact information. (Junjie Piao)

Piao said he didn't know how many bedrooms there were total in the house before he moved in. When he arrived, there were 12 bedrooms.

After a few months, Piao moved out because he didn't want to live in an "overcrowded" house, he said.

He couldn't get his money back from the landlord, and says Yuan still owes him $2,500. Piao filed two appeals with the province's Landlord-Tenant Board last year, but they were both dismissed. Yuan said he doesn't owe him any money.

Yuan told CBC News he does not own the house any longer. In response to 10 questions from CBC, Yuan wrote a brief email saying issues with the house were solved with the city inspector who came to see it last summer.

'He just felt we're ... foreigners'

Another student who lived there, Jerry Wu, found the house around the same time, in his second year at McMaster when he needed to find a place to rent off-campus.

"My first impression it was not bad because I didn't know what other houses looked like, because it was my first time (renting)," he said.

An online listing ad said the house has only eight bedrooms, not 12, and included a photograph of one of the house's two kitchens. (Kelly Bennett/CBC)

He said he paid a full year's worth of rent at $650 per month upfront, plus a deposit. He said the water in his bathroom was only ever all hot or all cold, and the landlord did not deal with it.

"He just felt we're like foreigners like so we don't need to, we don't know how to – we don't know the law or something," Wu said. "So he just took advantage of us."

Despite that, Wu stayed in the house until the end of his lease last August, he said.

A zoning violation issued

Last year, the city got a complaint about the dozen bedrooms. An inspector went out to have a look in May, and wrote up a zoning violation about the 12 bedrooms.

The owner, Yuan, told the enforcement officer that he was going to evict all the tenants and sell the house.

When the inspector came back, it was the end of July. The bedroom doors were still in place. There didn't appear to be tenants living in the house.

"All areas were common areas," a city spokeswoman said – which she said means that there would have been no locks on the doors.

The city inspector closed the file.

But now, almost a year after that zoning violation, the property has changed hands and there are still 12 rentable bedrooms in the house.

The city issued a zoning violation notice in May 2016 after visiting and seeing 12 bedrooms in the house. (City of Hamilton)

And the city has not offered an answer as to why the inspector felt that checking on the house in July, when students might be away or home for the summer, was sufficient in light of the violation.

Without those landlords providing all these students residences, the university will run into chaos. - Joseph Wenxu Guo, current owner of the house with 12 bedrooms

From the former owner's perspective, the issues were all settled last July.

"As you know that the city did issued a notice in May of last year for zoning issue. I went to city and discussed the issue with the inspector who issued the notice. The issue was corrected accordingly and in July the issue was solved," Yuan told CBC News in an email.

"The house was sold last September," Yuan wrote. "Hope these answered your questions."

Reactive, not proactive, enforcement

But the city did not go back after the sale to see how the house was being used after school started up again.

"The officer would not have gone back after the file was closed unless we continued to get complaints," said the city's bylaw spokeswoman, Ann Lamanes. "Due to the volume of complaints, our enforcement in this area is reactive, not proactive."

CBC News visited the house earlier this month and was allowed in for a look around on the main floor by one of the tenants. A long hallway of bedroom doors could be seen – seven in total on the main floor. A tenant living there said there are five downstairs.

You don't have to go to the house to see there are still multiple bedrooms being rented.

A forum for off-campus housing listing the house for rent, as of Thursday, as an eight-bedroom house with six bedrooms available.

Guo, the current owner, said the previous owner did all the renovations and he said there are no fire hazards at the house. He said he doesn't have all 12 bedrooms rented out.

"I heard that as long as you have less than three rental contracts, even with a higher number of students [living] at one house, the zoning officer will not bother you," Guo said.

A bylaw officer said that's not true.

Guo said zeroing in on his house was unfair.

"This rooming-house-for students-issue is a gray area around the university for many many years and it involved almost all the houses near McMaster University," Guo said.

Coun. Aidan Johnson said he and Coun. Terry Whitehead will propose a landlord licencing pilot project in their wards, both of which have significant student tenant populations. (Samantha Craggs/CBC)

Johnson said he and Coun. Terry Whitehead will propose a landlord licencing program next month to begin with a pilot in their wards, both home to a large student population. The fees charged to landlords could support more bylaw enforcement to get at bad situations and improve living conditions for tenants, he said.

"We don't have money to do the proactive enforcement that I would like to do, as we need to do," Johnson said. "So this is an argument for licencing."

kelly.bennett@cbc.ca