July 31, 2008
Saanich is trying a hot new pavement product for the second time.
And it's really not all that hot, says Trevor Howells, a quality controller with Capital City Paving. That's cool, because the new method is easier on the evironment.
"There's reduction of emissions," Howells said. "We reduce nitrogen dioxide by – it varies – by about 58 per cent, carbon dixide is reduced by 46 per cent ... and sulphur dioxide by 81 (per cent)."
The lessened impact on the environment is the whole point and why the municipality worked with Capital City Paving to patch up a section of Arbutus Road almost exactly one year after paving Maplewood Road with warm mix pavement.
Warm mix has less greenhouse gas emissions than hot mix because it's cooler. The warm stuff reaches a temperature of 100-120 C, in comparison to hot mix, which reaches 140-160 C.
Less energy is required to heat it and less oil is used in the heating, Howells said. It also takes less time to pave, easing the time of congestion traditionally caused by road work.
Warm mix doesn't require cooling time before compacting. The lower temperature also poses less risk to paving crews. Warm mix, which is relatively new to the North American paving market costs more than hot mix
