TORONTO - There are signs that some of Canada's major house markets have become overheated, although most others have shown a more healthy rate of moderate growth, according to a national real-estate sales organization.

Prices for all key housing types were up more than 10 per cent across Canada in the first quarter on a national basis, according to the Royal LePage survey released Thursday

But Vancouver and Toronto prices rose much more dramatically -- about 20 per cent in some cases -- and the head of Royal LePage Real Estate Services suggested they may have risen too far in those local markets.

`House sale data from the past two year period shows tremendous variances in terms of how different cities reacted to the recession," said Phil Soper, president and chief executive of the big real estate broker.

`In Vancouver and Toronto, for instance, the dramatic unit sales fluctuations exhibit a significant degree of market irrationality: inordinately fearful when faced with poorer markets; and overly enthusiastic when the tables turned."

The Royal LePage survey found the average price of detached bungalows in Toronto climbed to $459,107 in the first quarter, up 13.3 per cent from a year ago.

Standard two-storey homes in Toronto were up 13.2 per cent, rising to $562,150 while condo prices rose a more moderate 10 per cent to $317,579.

In the Vancouver area, detached bungalows climbed an eye-popping 21.8 per cent to $906,045 while two-storey homes were up 19.2 per cent to $987,5000 and standard condos were up 15.7 per cent from early 2009, rising to $470,000.

Those two cities benefited from strong local economies and comparatively low mortgage rates which have helped boost housing in general across the country. The Vancouver economy gained an economic boost from the Winter Olympics and Toronto's strength in financial and other services underpins the city's economy even as Ontario's manufacturing sector streamlines and cuts thousands of jobs.

In contrast, Soper described a Montreal as "an example of a city where the market has been much more stable and homeowners there seem quite happy with the relatively slow pace of change."

Despite the rise in prices, Soper said he expects the market to slow down later in the year as mortgage rate increases begin to dampen demand for home loans and make it more difficult for would-be homebuyers to afford higher-priced houses.

The Bank of Canada is expected to begin pushing up rates this summer by between half and a full percentage point by the end of the year as the central bank tries to fight inflationary pressures in the economy. Many banks have raised their mortgage rates already by more than half a point in anticipation of the broader rate increases later this year.

"Even in our most frenzied pockets of market activity, the inevitable rise in interest rates coupled with home price appreciation will rein in demand as affordability erodes," Soper said.

"Expect house prices to continue to rise, but the rate of appreciation should ebb steadily, month by month, throughout the remainder of the year, as balance returns to the industry."

In its report, Royal LePage said the average price of a bungalow in Montreal climbed by 7.2 per cent to $249,172, while the price of a standard two-storey house increased by 7.6 per cent year over year to reach $355,109 and the average price of a condominium increased by 7.6 per cent, to $222,244.

The survey found that, on a national basis, the average price of a detached bungalow in Canada rose to just over $329,000 in the first three months of this year -- up 11 per cent from the first quarter of 2009.

Standard two-storey homes rose 10.3 per cent, to about $365,000, while condominium units increased by 10.9 per cent to just under $229,000.

In Atlantic Canada, house price increases were modest, with the exception of St. John's, which saw year-over-year increases of between 17.6 and 18.4 per cent. The average price of a standard two-storey home in St. John's jumped to $313,775 in the latest quarter.

Saint John, N.B. also showed strong growth in detached homes, with bungalows up 16 per cent year-over-year to $233,775.

In Halifax, the price of a standard two-storey house rose 6.8 per cent to $278,267.

Strong economic performance in Saskatchewan continued to bolster the housing market in Regina, where the average two-storey house price jumped nine per cent to $267,000.

Average prices in Winnipeg jumped between 9.6 and 11.9 per cent year-over-year, with detached bungalows reaching $259,313 in the first quarter.

Housing markets in Alberta continued to recover in the first quarter of this year. Although still averaging lower than pre-recession prices, all housing types in Calgary saw year-over-year price increases of between seven and 10.6 per cent.

In Edmonton, home prices remained flat or increased year-over-year, with standard two-storey homes experiencing the largest increases at 5.2 per cent.

Royal LePage, with a network of 14,000 real estate agents, is part of the Brookfield group of companies that includes Brookfield Real Estate Services Fund.