At DC Construction Services, we’ve written a few blog posts weighing the comparative merits of asphalt and concrete. You can read a broader overview of that debate here. In this post, however, we will be looking at a specific issue—environmental impact. When considering a paving project, which is the “greener” choice: asphalt or concrete? The answer, of course, is not simple. Let’s examine the different factors.
Asphalt is a byproduct of oil and, like other petroleum byproducts, is not very environmentally friendly in terms of its “embodied energy cost”—the energy required to make a product.
Concrete, by contrast, is a composite material made up of coarse and fine aggregate cemented together. At face value, these components are less harmful than oil-derived products. However, the resource-intensive process necessary to acquire these materials cancels out that advantage. So, in terms of composition, asphalt and concrete are neck and neck.
When well-maintained, asphalt pavement should last 30-40 years. However, this requires regular maintenance including crack filling and sealcoating, which utilizes various resources. Concrete typically has a longer lifespan of 40-50 years. Therefore, in terms of longevity, concrete comes out ahead.
Both materials boast commendable recyclability. Many of the components that make up concrete are recyclable. However, asphalt is 100% recyclable. This means that old asphalt can be removed and converted into new asphalt. There is no limit to how many times asphalt can be reused. This conversion cycle significantly reduces resource waste and pollution, putting asphalt over the edge, in terms recyclability.
Looking at these key points, it is clear that the two materials are very comparable in terms of environmental impact. There are other factors that could affect this issue, such as toxicity, reflectivity and friction. However, studies have shown that any differences in these areas are almost negligible.
One way to determine which material is “greener” for your project is to consider the area in question. Paving a parking lot in the southern United States? Asphalt is both impractical and environmentally unsound. When temperatures near or exceed 100ºF, asphalt can soften, damaging its integrity and producing toxic runoff. Working in a state far from concrete resources? Consider eliminating added expense and pollution by opting for asphalt. The relative environmental impact depends on your circumstances.
Are you unsure whether asphalt or concrete is right for your commercial paving project? Contact DC Construction Services today. We’d be happy to answer any questions and offer our professional input.