Canada is tightening mortgage rules over concerns Canadians are taking on too much debt, according to AP. Finance Minister Jim Flaherty said Monday the maximum amortization period for government-insured mortgages will be shortened to 30 years from 35 years. Ottawa is also lowering the limit on how much money Canadians can borrow using their homes as equity to 85 percent of the value, from 90. The new rules go into effect March 18. Flaherty says some Canadians are «borrowing to the max at low interest rates.» Household debt was a record 148 percent of disposable income in third quarter last year, exceeding the U.S. level of 147 percent. The government wants to ensure there is no mortgage meltdown in Canada when rates go up.