It's that time of year when furnaces get a lot of use. And you may be thinking about a replacement or perhaps getting one more year out of the old one. That delay may cost you a lot of money.

Starting in the New Year all new furnaces imported into Canada will have to be high efficiency. Glenn Cooke, a Carrier supplier, says it's a federal government law.

"That's going to create some challenges for home owners and HVAC [Heating, Venting and Air Conditioning] contractors alike," Cooke said.

The challenge is you can't just take out an old furnace and replace it with a high efficiency one.

Mid efficiency furnaces can use an existing chimney or B-vent pipe but high efficiency can't. It has a plastic pipe through the roof or through a side wall.

"It can cause some issues in finished basements where you can't get access to an outside wall or the roof without some major renovations," Cooke said. "It will take one to two days easily so it won't be the usual four to five hour installation. It's going to be much more work so the cost will go up as well."

The cost will be about double or more what a mid-efficiency would cost. Furnace companies are getting lots of calls from people wanting to beat the deadline.

If there are any mid efficiency furnaces in stock after the new year -- furnace companies may sell them until they are gone. After that:

"There will be no exceptions. NRCAN has basically said there are no exceptions to this rule," Joy Chandna of Papa Plumbing and Heating explained.

So if your old furnace is on the way out you might not want to get one more year out of it. That could be an expensive delay.

To find out more about the new regulations you can find out more at the Ministry of Energy, Mines and Petroleum Resources.

With a report from CTV British Columbia's Chris Olsen.