Canadian housing starts rose in July on growth in western British Columbia, even as groundbreaking on single-detached homes fell in Toronto where activity has cooled after the province introduced measures to rein in a frothy market.

The seasonally adjusted annual rate of starts rose to 222,324 units in July, the Canada Mortgage and Housing Corporation (CMHC) said on Wednesday, topping economists' expectations for 205,000. June's figures were revised up to 212,948.

Although parts of Canada's housing market have started to cool, homebuilding has remained solid and the six-month average for housing starts rose to 217,550 on increased activity in the provinces of British Columbia and Alberta.

"Housing starts aren't showing many signs of cooling down this summer," CIBC economist Andrew Grantham said in a note to clients.

The housing market continues to surprise economists who had predicted residential construction will become a drag on economic growth before the end of the year, Grantham said.

Seasonally adjusted starts jumped 20 per cent in British Columbia, lifted by the multi-family segment. That increase came as the number of completed and unsold homes has hovered near a record low in recent months, CMHC's chief economist Bob Dugan said.

Ontario starts rose 1 percent. In the provincial capital of Toronto, Canada's largest city, starts for single-family homes fell 8 percent, though groundbreaking on multi-family homes jumped 36 percent.

The strong increase in starts for semi-detached and town homes in the city suggest affordability concerns are driving demand for less expensive housing types, the CMHC report said.

Toronto home sales have declined for four consecutive months since the provincial government took steps to try to rein in the housing market, including imposing a foreign buyers tax.

As there can be a long lag between demand and new construction, the slowdown in sales in Ontario will have a greater impact on starts next year, Grantham said.

Separate data from Statistics Canada showed the value of Canadian building permits unexpectedly rose in June on increased plans for commercial buildings, though construction intentions for single-family homes decreased.

The 2.5 per cent increase exceeded economists' forecasts for a decline of 2.0 per cent. For the second quarter, building permits rose 10.4 per cent compared with the year before, the biggest increase since the third quarter of 2012.