Nov 05, 2007

Concrete Choices for the Environment

Because of today's environmentally conscious marketplace, concrete, one of the oldest and most versatile building materials on the planet, is now beginning to stand out as a solution to sustainable construction requirements. You can't pick up a newspaper or construction-related publication today without seeing some kind of article about "green building" or "sustainable construction."

Construction companies are now seeing the possibilities of concrete’s unique applications, such as pervious pavements and insulated stay-in-place form construction.

The U.S. Green Building Council developed a program called Leadership in Energy and Environmental Design (LEED) and has become the prominent green building rating system. There are four different thresholds for LEED certification recognizing varying levels of achievement: Certified, Silver, Gold and Platinum. LEED-NC (New Construction) promotes improved practices in site selection and development, water and energy use, environmentally preferred construction products, waste stream management and indoor environmental quality. Within each category, project teams choose which credits to pursue based on their environmental and performance goals.

The use of concrete can contribute to earning more points toward project certification than any other building material. One such credit where the use of concrete makes a difference toward earning points is under the category of “sustainable sites.”

In this category, the use of pervious concrete pavement qualifies for credits SS 6.1 Stormwater Design-Quantity Control and SS 6.2 Stormwater Design-Quality Control. Conventional impervious pavements, particularly parking lots, collect pollutants that can be washed into streams, lakes and oceans. Pervious concrete pavements can reduce or eliminate stormwater runoff and permit the treatment of pollutants on site. By capturing rainfall and allowing it to percolate into the ground, soil chemistry and biology are allowed to treat the polluted water naturally.

Since there is little to no runoff, aquifers are replenished and flooding is minimized. Costly conventional stormwater collection systems can be reduced or eliminated by using pervious concrete in a parking area to retain stormwater, which in turn allows for more efficient land development.

Earning credit SS 7.1 Heat Island Effect, Non-Roof could be accomplished by using light colored concrete pavement or an open grid pavement system like pervious concrete for at least 50% of the site's hardscape.