It made that assessment in its annual review of the Canadian housing market released Thursday, comparing house prices in Canada and the U.S. controlling for differences in exchange rates and the cost of living.
"The Canadian 'premium' could be a cause for concern," the report said.
“CMHC is analyzing these differences, in order to understand the reasons for the price differential, be they structural, temporary or reflective of relative overvaluation in Canada,” it added.
The report follows the trajectory of house prices in Canada and the U.S. since 2000, pointing out that U.S. prices were rising faster than Canadian prices before the financial crisis.
Then the sharp shock of numerous mortgage defaults pushed prices sharply lower in the U.S., down 32 per cent from their peak by 2009. Canadian prices had a brief dip in 2008, but otherwise continued a gradual rise.
“As economic conditions improved, the Canadian housing market entered a period of relatively stable house price growth that permitted price levels to recover by December 2009 … unlike the U.S. experience,” the report said.
Since the 2007-08 period Canadian house prices have continued to outstrip U.S. prices, the report found.
Average Canadian home prices at the end of 2013 were about $400,000 on a cost-adjusted basis, compared with about $250,000 in the U.S.
Not predicting a bubble
CMHC officials have said they are not worried about a housing bubble, though they sound a note of warning about urban markets such as Toronto and Vancouver where housing is becoming increasingly unaffordable.
The housing market is “robust” and only some parts are overvalued, CMHC CEO Evan Siddall said in an Oct. 20 speech in Toronto.
The strength of the Canadian housing market and concerns about a possible housing crash have garnered much attention in the past two years amid the climb in prices.
Last month, the Bank of Canada raised concerns about the "renewed vigour" it detected in the housing market and consumer spending since the summer.
However, both Prime Minister Stephen Harper and Finance Minister Joe Oliver have downplayed the susceptibility of the Canadian housing market to a sharp downturn.
Overall, the CMHC report depicted a stable housing market with homeowners able to manage their mortgage debt.
Condos now 1 in 3 new builds
One of the big trends CMHC noted in its report was the rise of condos as a share of new housing stock.
Condominiums accounted for more than one-third of all Canadian housing starts last year, and more than half of the total in Canada’s biggest cities.
The federal agency says condominium apartment starts represented less than one in five Canadian housing starts in the early 1990s, but that proportion had grown to more than one in three in 2013.