Concrete Decisions 8
CANADIAN HOMES & COTTAGES
Green Construction
This Vancouver builder plans to warm clients to the merits of concrete construction BY
Carolyn Heiman PHOTOS BY John Yanyshyn
E
xperiences from another part of the world often allow people to see things from a different vantage point. It can also change how they do things. That’s the case for homebuilder Damon Gray who moved from New Zealand to British Columbia, the land of big trees and wood frame home construction. From the country where exorbitant electricity costs make it a sin for builders not to do everything possible to cut energy HOMESANDCOTTAGES.COM
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RIGHT Splashes of playful colour add a touch of warmth. BOTTOM Concrete, supplemented with insulation, is used to reduce heating and cooling energy requirements.
Good for the Environment Throughout construction he had an eye on making decisions based on what was best for the environment. Trees that had to be removed for the building envelope were used in construction and surplus concrete was recycled.
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CANADIAN HOMES & COTTAGES
costs, he imported ideas about constructing passive homes from concrete. While relatively uncommon in Canada, concrete sandwich panel construction is increasingly common in New Zealand where concrete, supplemented with insulation, is used to significantly
His home won several awards at the Canadian Home Builders’ Association, Vancouver Island, Building Excellence Awards reduce heating and cooling energy requirements. Gray believes the construction methodology has a place in Canada too. But, changing cultural and business biases often have hurdles. Gray says people ask about the cost of building with concrete, how
Green Construction
ABOVE Many of the rooms are drenched in sunshine thanks to large windows and sliding doors. BELOW A smooth concrete patio provides a clean spacious look.
it fits with home building codes, and whether the material allows elegantly-designed homes. Questions even arise around how to hang pictures in a concrete house. Gray has easy answers to all those questions. Plus, after building more than 17 homes abroad using the technique, he used concrete sandwich construction for his home on Vancouver Island. He found that while construction costs are about 10 per cent higher, those costs are quickly offset by lower energy and maintenance costs. Depending on the policy, home insurance costs may also be lower. The building codes accommodate the construction technique with small adjustments to approval processes. And in terms of livability, his lovely and carefree home where he and his wife Annie and two young boys live, is proof that there are no design and aesthetic limitations imposed by the construction materials. So what makes these homes so efficient? Gray says construction techniques essentially create an uninterrupted blanket of insulation around a home, eliminating heat loss that can escape around studs. Construction was faster because it takes considerably less time to pour insulated concrete slabs and tilt them into place using a crane, than it does to frame a house. A concrete sandwich home can be constructed to roof height in as little as two days. Gray studied the Canadian Building Code carefully to understand how concrete construction techniques would fit within the rules. Initially he was worried that obstacles were large and complex and he hired consultants to guide him. But, when he read the code carefully he recognized the section relevant and related to the building envelope was not applicable because a mass wall construction no longer requires a rain screen. “It is a simple system. People try to make it complicated.” After living in the 3,000 square foot, L-shaped home with its sun-drenched rooms and splashes of playful primary colours, Gray says there are only minor things that he would do differently such as install a cheaper and smaller hot water tank because the 85 gallon tank is overkill based on their usage. His monthly hydro bill for the home, which has generous overhangs to keep HOMESANDCOTTAGES.COM
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Green Construction
the summer heat out, and solar panels that provide hydro credits, works out to about $70 a month. “I don’t want to have to work three days to pay my electrical bill,” Gray says. And, as a busy father with his company, NZ Building, to run, he’s not interested in spending his weekends on house maintenance. “I only want to worry about keeping it pretty, not painting and fixing rot,” that naturally happens over time with wood frame homes. Simply described, concrete sandwich construction is much like it sounds: two pieces of steel reinforced concrete ‘bread’ are sandwiched around an insulation filling. These panels are then mechanically connected together to make the size and shape of the house. He’s designed small casting tables for pouring the panels on site. “They are easy to use and they provide a high degree of measurement accuracy,” which further cuts the 12
CANADIAN HOMES & COTTAGES
FAR LEFT An exposed brick wall behind the bar adds character. BOTTOM LEFT Sliding barn-style doors make for easy access in tight spaces. BELOW A few elements of wood outdoors complement the natural setting.
risk of unexpected labour costs arising from miscalculations. “I’m not on the leading edge of the construction technique, but I am on the leading edge of putting it together here.” Keeping him on the leading edge is the environmental data he continues to collect from his own home. It’s wired to collect information on temperature fluctuations that influence insulation and designs for other homes. For example, on any given day he knows exactly how much hydro he is using for TVs, computers and other electrical appliances. He’s learned that installing electrical in-floor heating would have been more cost effective than the hot water in-floor heating he did install. Most importantly, he has established that the payback on the initial
His monthly hydro bill for the home, which has generous overhangs to keep the summer heat out, and solar panels that provide hydro credits, works out to about $70 a month higher costs of concrete is quickly returned by lower energy costs and lower labour costs of construction. All the care and attention has paid off, as has Gray’s courage to try something new. This year his home won several awards at the Canadian Home Builders’ Association, Vancouver
Island, Building Excellence Awards. The two awards include one for the best single family home between 1,500-and 3,000-square-feet and the best innovative feature for the concrete sandwich panels. The awards say it all — a beautifully-designed home using concrete in an innovative way really is possible. HOMESANDCOTTAGES.COM
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