March 23, 2009

CALPORTLAND

Design intricacies are possible with polished concrete floors. The concrete doesn’t have to travel far to reach a worksite, making it eligible to contribute LEED points to a project.

Sustainable building includes concrete flooring

BRIAN MARTIN

correspondent

Talk about a green floor and many people will immediately think of hardwood because it’s a natural product.

Concrete isn’t the first often the first that pops to mine, but perhaps it should be.

Other floor coverings such as vinyl or marble, carpet or wood are arguably not as environmentally friendly.

After all, vinyl and carpet are based largely on petroleum products and normally require transport by truck or train over vast distances.

Hardwood sounds good, but a lot of the trees in B.C. are softwood.

Hardwood flooring normally travels thousands of kilometres from the eastern U.S. or Canada.

Concrete, on the other hand, is distinctly local and it is rarely shipped any considerable distance.

Bruce Wilmer is the vice-president in charge of the Vancouver ready-mix operations for Lafarge, one of the world’s largest concrete firms.

He knows concrete and he knows it can be environmentally friendly.

“In the last few years with the advent of sustainable development, our industry has aligned itself – sometimes almost by chance – with the whole LEED certification system,” Wilmer said.

He said one of the major changes to the process has been the reduction in the amount of cement used in its production.

The process of producing cement is energy-intensive and one side effect is a considerable output of CO2.

By reducing the amount of cement in concrete, ready mix producers are making it more environmentally friendly.

According to the Cement Association of Canada, the cement industry managed to reduce its CO2 emissions by about 30 per cent, since it started measuring its environmental performance in the mid-1970s.

Andrew Vizer is director of engineering for the Western Region of the Concrete Association.

He likes to point out the actual energy efficiency of using concrete in buildings – very much including the use of concrete floors.

“Buildings use an horrendous amount of energy both for heating and for cooling,” he said.

He pointed out that mechanical systems can be designed to use the thermal mass of a concrete building to assist in both.

Furthermore, concrete floors don’t have to be ugly.

In fact, polished concrete floors have won no end of design awards.

CalPortland is a major player in the cement and concrete field. It has locations throughout the western United States, B.C. and Alberta.

Dave Frentess is its marketing director for the Northwest Region and works from offices in Vancouver, Washington.

Frentess is well versed in the ins and outs of polished concrete floors.

“The bottom line regarding concrete floors is that a properly done concrete floor eliminates other treatments and coverings, culminating in a less is more approach. This applies to both commercial and residential settings.”

Polished concrete floors, said Frentess, can provide commercial floors that don’t show traffic wear.

Providing new, artistic decorative concrete surfaces are the most common advantages of polished concrete.

Frentess said there has also been considerable growth in exposed concrete floors in cafes and restaurants.

There are no tile joints, they’re easy to keep clean and free of bacteria and they are hard-wearing.

Frentess said that in terms of energy efficiency, concrete slabs help cool during the summer and, with the addition of in-floor systems, are also highly effective heating systems.

He pointed out that using concrete as a finished material makes sense from a green building perspective, as it minimizes the amount of materials needed to complete a project.

Following the LEED rating system, bare concrete floors can make contributions towards points in a number of categories.

However, he pointed out that an installer must know what they’re doing.

The subgrade preparation can be critical, with well graded granular materials that are properly compacted.

The subgrade should be moist but not saturated.

Contractors must also order a mix that will take their pattern.

He also said that working with decorative concrete means a considerable increase in labor.

Finally, he warned contractors to be sure their customers understand that no coloured slab will perfectly match any colour chart.

“Expect some slight variations in colouring,” he said. “Concrete is made with natural materials, so variations are normal.”

Print | Email | Comment