Landing an affordable mortgage may become even more difficult in Canada if the country’s banking regulator moves forward with rules reducing the length of uninsured home loans.

The move — if it happens — is meant to prevent a housing market collapse in the face of record-high prices, record-low interest rates and the appearance of potentially irresponsible lending practices.

But it will likely raise the alarm in the home lending industry, which has already been complaining about Finance Minister Jim Flaherty’s move last year to tighten mortgage rules.

Flaherty last year reduced the maximum length of a mortgage covered by Canada’s government mortgage insurer, CMHC, to 25 years from 30, and reduced the amount you can borrow against the value of your home.

But the Office of the Superintendent of Financial Institutions (OSFI), which regulates Canada’s banking sector, is apparently growing worried about uninsured mortgages — those not covered by CMHC.

OSFI is contemplating limiting the maximum length for any mortgage to 25 years, from the current 35, according to Canadian Mortgage Trends.

If that were to happen, lenders would no longer be able to reduce monthly payments by stretching out a mortgage’s amortization over 35 years, and monthly payments for many prospective borrowers would have to be higher. That, in turn, would price some people out of the market.

The Globe and Mail cites a banker's estimate that about 40 per cent of uninsured mortgages have amortization periods greater than 25 years.

The volume of home sales in Canada was 25 per cent lower in April of this year than it was during the same period last year, although prices have held up and are still about 62 per cent higher, on average, than in the U.S.

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  • Quebec: $9.8 million

    The most expensive house for sale in Quebec is located in the suburb of Laval, on the shores of the river separating it from the island of Montreal. The house has six bedrooms and eight baths on 9,800 square feet of land.

  • Quebec: $9.8 million

    The house features a heated inground pool.

  • Quebec: $9.8 million

    A very ornate living room.

  • Quebec: $9.8 million

    The dining hall.

  • Quebec: $9.8 million

    Twin staircases flank the lobby.

  • Quebec: $9.8 million

    The kitchen features a large island.

  • Quebec: $9.8 million

    A spacious bathroom.

  • Quebec: $9.8 million

    The media room.

  • Quebec: $9.8 million

    The wine cellar.

  • New Brunswick: $1.9 million

    A custom-built, 8,300-square foot home with four bedrooms on three acres of land in Shediac Cape. The house features its own elevator.

  • New Brunswick: $1.9 million

    A fully equipped gourmet kitchen with large centre island opens to breakfast room.

  • New Brunswick: $1.9 million

    Vaulted ceiling adorn the main room, and the entrance foyer features inset ceiling lights and a chandelier.

  • New Brunswick: $1.9 million

    Dining room.

  • New Brunswick: $1.9 million

    The second floor offers magnificent master suite with sitting area adorned by propane fireplace, access to balcony, dressing room, luxurious ensuite and guest room/bedroom with ensuite.

  • New Brunswick: $1.9 million

  • Nova Scotia: $6.7 million

    This two-year-old property on Ketch Harbour near Halifax has three bedrooms and four baths, made from high-grade Italian limestone. But the property doesn't seem to be selling; it was the most expensive property for sale in Nova Scotia the previous time HuffPost compiled this list, in October, 2012.

  • Nova Scotia: $6.7 million

    A slick, modernist bedroom with stunning views.

  • Nova Scotia: $6.7 million

    Stunning views of the ocean.

  • Prince Edward Island: $6.9 million

    Located above the bluffs of P.E.I.'s stunning North Coast, this house features six bedrooms and nine baths, and clocks in at a stunning 13,360 square feet.

  • Prince Edward Island: $6.9 million

    The kitchen is a blend of rustic and modern.

  • Prince Edward Island: $6.9 million

    The study.

  • Prince Edward Island: $6.9 million

    A bedroom with fireplace.

  • Prince Edward Island: $6.9 million

    Upper levels open on to the great room.

  • Prince Edward Island: $6.9 million

    A spiral, three-story staircase.

  • Prince Edward Island: $6.9 million

    A snug bedroom with fireplace.

  • P.E.I.: $6.9 million

    Take the virtual tour.

  • Newfoundland: $1.95 million

    This lime green, six-bedroom, nine-bath house just outside of Corner Brook is the most expensive property for sale in Newfoundland. The two-story, 6,000-square-foot house features a walkout basement that offers access to the back yard.

  • Newfoundland: $1.95 million

    The main floor has a floor-to-ceiling fireplace.

  • Newfoundland: $1.95 million

    The realtor describes the gourmet kitchen as a "chef's dream."

  • Newfoundland: $1.95 million

    "Cathedral ceilings" top the second floor.

  • Newfoundland: $1.95 million

    The back yard.

  • Ontario: $19 million

    The most expensive house for sale in Ontario is a condo in Toronto's posh Yorkville, in new building across the street from the Royal Ontario Museum. Suite 1400 at 155 Cumberland Street has four bedrooms and five bathrooms on two stories, with tons of balconies and verandas surrounding the whole thing.

  • Ontario: $19 million

    Swank terraces adorn the building.

  • Ontario: $19 million

    The unit has 5,000 square feet of terraces, and a pretty nice view.

  • Ontario: $19 million

    The second floor.

  • Ontario: $19 million

    Looking south towards the downtown core.

  • Manitoba: $4.3 million

    A custom-built, 7,851-square foot home with five bedrooms and nine baths in Winnipeg's Ridgedale neighbourhood.

  • Manitoba: $4.3 million

    The great hall.

  • Manitoba: $4.3 million

    The living room.

  • Manitoba: $4.3 million

    A very post-modern entertainment room.

  • Manitoba: $4.3 million

    The games room.

  • Manitoba: $4.3 million

    A rustic kitchen, despite all the amenities.

  • Manitoba: $4.3 million

    Now that's a bathtub.

  • Manitoba: $4.3 million

    The gym.

  • Manitoba: $4.3 million

    The view from the back.

  • Saskatchewan: $2.8 million

    This is the only image we have of the most expensive property for sale in Saskatchewan, as the seller has not provided any other photos. The realtor describes this five-bedroom, six-bath house on 4,300 square feet near Saskatoon as a "must see property." We'll have to take his word for it.

  • Alberta: $12.7 million

    Six bedrooms and eight baths in this house located in the scenic mountain town of Canmore. The house was an Architectural Digest showpiece.

  • Alberta: $12.7 million

    Vaulted ceilings in the great room.

  • Alberta: $12.7 million

    The kitchen.

  • Alberta: $12.7 million

    A hidden staircase leads to the wine grotto.

  • Alberta: $12.7 million

    The media room.

Some economists expect prices to start following the downward trend in sales at some point this year. Will Dunning, an economist with the Canadian Association of Accredited Mortgage Professionals, predicts house prices will start falling this year and has estimated that Flaherty’s rule changes will kill 190,000 jobs related to construction and real estate. Further tightening of the rules would likely further dampen housing activity.

(Not everyone agrees that Flaherty’s rules began the housing market’s slide, as evidence exists some weaker elements of the housing market were already in decline when the rules were put in place.)

In an email to the Globe and Mail, OSFI stressed no decisions have been made.

We are working to determine the desirability of some changes given current conditions in housing markets and recent trends in household indebtedness,” OSFI spokesman Brock Kruger told the Globe.

Flaherty, Bank of Canada Governor Mark Carney and OSFI have all expressed concerns that Canada’s housing market has become overheated, with prices rising too high and borrowers taking on too much debt.

But the industry has been busily working against Flaherty’s attempts to cool the market, offering rock-bottom interest rates and various forms of discounts and rebates.

Canadian lenders have to get CMHC insurance for any mortgage on which the buyer puts less than 20 per cent down. But in the wake of the tougher CMHC rules, lenders have been increasingly turning to uninsured mortgages with longer amortization periods to get people to buy homes.

Even before the new rules came in, OSFI appeared concerned that segments of Canada’s housing market are beginning to resemble the subprime lending mess in the U.S. in recent years.

Home Capital, a lender that focuses on customers who have been rejected for mortgages by the big banks by offering uninsured loans, was recently singled out by a renowned hedge fund manager as a company that could be in big trouble if house prices decline. (Home Capital claims that everything is fine with its business model.)

Other market observers and investors have even suggested Canada’s banks could face financial difficulties due to their exposure to Canada’s housing market.

Our review reveals that the average loan/value ratios of U.S. banks just before the housing collapse are similar to those we currently see on residential loans in Canada,” investment research firm Morningstar recently said in a report.

“More important, their distribution is eerily similar. … [I]t appears that the CMHC and the banks have significant risk of losses or impairment to capital levels.”

Despite the negative sentiment recently, Canada’s banks continue to ride high in the rankings of the world’s safest, and economists from Canada’s big banks pretty much unanimously agree the housing market is in for a soft landing, and not a U.S.-style collapse.