You can't always judge a house by its cover - especially if it's built with concrete.

To the unknowing eye, a concrete home will likely look the same as adjacent houses. It can have vinyl siding, brick or a stucco exterior, but that's where the similarities stop.

Industry officials say concrete homes are more energy efficient, are able to withstand fires longer than traditional wood-frame homes and are almost impervious to Mother Nature's violent side should she decide to unleash a tornado or some other form of unpleasant weather.

While concrete residential homes are still in their infancy in Alberta, it's estimated that 700 to 800 of these homes are built annually in the province, says Ed Kalis, executive director of the Edmonton-based Alberta Ready Mixed Concrete Association.

MindTravellers photo
This house in Old Glenora looks like a wood-frame building, but it's actually concrete.

"From an industry standpoint, we started promoting the insulated concrete form (ICF) concept for below grade and above grade in the early 1990s and at that time there were virtually none done in the province of Alberta," says Kalis. "Now it's a growing market and it's increasing by about 50 per cent every year."

An ICF home uses more concrete than other homes and can be built in practically any form, from a typical bungalow to a two-storey home with a walkout.

"It utilizes more concrete in the structure, but provides the consumer or homeowner with a more energy-efficient home. It's very quiet and it's really not susceptible to tornadoes or natural disasters from weather," adds Kalis.

Edmonton-builder Dabrro Homes specializes in building ICF homes. It recently won the 2006 Award for Design Excellence honourable mention presented by the Cement Association of Canada.

According to the association, "they provided hard evidence that ICF forms are the best home-building solution for marrying energy efficiency with superb aesthetic appeal."

Dabrro, a company that has been around for more than 10 years and started as a small family-based operation in rural Alberta, moved to Edmonton five years ago.

"We wanted to raise awareness regarding energy-efficient housing. Four years ago we put up our first ICF home, from footings to rafters, and we did that to show people the benefits of building with concrete and ICFs," says Dabrro sales manager Darren Graff, of the house that was built in Leduc, just south of Edmonton.

In the last four years, the company has shifted its focus away from wood to building ICF homes exclusively. "We've kept our focus on residential homes," building between 12 and 15 custom homes a year, says Graff. "We build on acreages and this past year we've focused on infill products in the city."

It was an Edmonton infill project in Old Glenora that won the award for Dabrro. The same venture landed Dabrro the Energy Efficiency Award from the Canadian Home Builders' Association - Edmonton Region at its recent Sales and Marketing (SAM) Awards.

To build that home, or any ICF home, polystyrene forms or blocks are used.

"It's like Lego on steroids," says Graff. "The polystyrene blocks are four feet long and 16 inches tall. You stack your house up just like you were playing with Lego and fill the polystyrene blocks up with concrete and that polystyrene form stays on and acts as insulation for the house."

All exterior walls are concrete. Inside walls are still woodframe, as the ICF builders are focused on the building envelope.

Graff says Dabrro's ICF homes are on average 44 per cent cheaper to heat and 32 per cent cheaper to cool than a woodframe home. "You will cut your energy bills in half," he predicts.

Once a builder is familiar with constructing an ICF home, it should take roughly the same time to build as a similar woodframe home.

The concrete not only makes the homes more resistant to severe weather, they also have a three-hour fire rating (the time it takes a fire to burn through a wall) compared to a 15-minute fire rating for a woodframed building, notes Graff.

Costs to build are only about seven per cent higher than building the same house with wood framing.

According to the Canadian Home Builders' Association - Alberta, ICF homes are now more common.

"It's becoming more popular. It definitely has a lot of possibilities though it is a niche market," says executive officer Grant Ainsley.

"The feedback we hear from builders is that there's a learning curve. They do need to have some education. What I have heard is that it takes considerably longer the first time the crew builds a home like that, but as time goes by, it goes down considerably."

Possibly one of the only factors working against ICF homes is that the general public is unaware of them.

"Once are homes are finished, they look like any other home," says Graff. "The only thing different from a normal home is the window sill, as the walls are a foot deep. You could live by one and you'd never know."

(Laura Severs can be reached at laura@businessedge.ca)