If you are planning to resurface your driveway, the first thing you should consider is how much space you really need to park your cars. By reducing the paved surfaces around your home to a minimum and using permeable materials, you can decrease the impact your driveway has on the environment and beautify your property.
Driveways can occupy a large area and are typically surfaced with asphalt, a relatively low cost, durable material. While asphalt is solid, slip resistant and can withstand repeated and intensive usage, it’s impermeable and prevents rain water and melting snow from slowly soaking into the ground. This contributes to rapid runoff of surface water toward the storm sewer system and natural bodies of water.
This runoff can transport pollutants such as road salt, oils and other substances and can adversely affect water quality and aquatic life. Asphalt also makes urban areas feel hotter in the summer since it absorbs solar rays and re-radiates them as heat. Impermeable surfaces also limit the amount of rooting space available to sustain healthy trees.
By assessing your needs, you may discover you can downsize your driveway.
If your driveway is used mostly to access your garage, it may not need to be more than 2.4m (8 ft.) wide for the average car. You can keep the length to a minimum by making it as direct as possible between the road and garage. Another approach is to install two strips of paving and plant grass or a groundcover that tolerates dry conditions between the strips.
In addition to limiting its size, you can surface your driveway with a more permeable material such as interlock pavers, loose aggregate or porous asphalt or concrete. While all of these options can be environmentally friendly, you’ll need to consider each material’s level of durability, suitability and cost.
Permeable Interlock pavers
A popular choice for driveway surfacing is permeable interlock pavers. They come in a vast array of colours, sizes, shapes and textures and can be installed in an infinite number of patterns. Several companies offer permeable pavers that have engineered gaps between the pavers that are larger than standard interlock applications and are designed to maximize stormwater infiltration.
Loose aggregate
Loose materials include river washed pebbles, pea gravel, stone chips, crushed stone, brick or concrete. These loose surfaces are relatively inexpensive, they are the most flexible for curving or irregular layouts and they allow water to seep slowly into the ground. However, some municipalities don’t allow loose aggregate to be used for driveway surfacing so be sure to check it out first.
Porous asphalt
While asphalt that is typically applied is impervious, you can consider a more permeable option. Porous asphalt uses larger sized stone particles than regular asphalt and lets water drain through the voids, helping to reduce runoff and increase infiltration. The same concept is also applied to porous concrete.
When it comes to driveways, you can choose from a variety of materials, colours, textures and shapes. To help you learn more about landscaping your home, Canada Mortgage and Housing Corporation has a publication called Landscape Guide for Canadian Homes available for $19.95, as well as free About Your House fact sheets on a variety of landscaping topics. Order your copy at www.cmhc.ca or call 1-800-668-2642.
Mark Salerno is the Corporate Representative for the Greater Toronto Area at Canada Mortgage and Housing Corporation. You can reach him at 416-218-3479 or e-mail him at msalerno@cmhc.ca.
