There's a type of concrete that let's water pass right through it!

Pervious concrete, also known by a few other names such as porous concrete and permeable concrete, is a special type of concrete that let's water pass right through it! This helps reduce runoff from a site and allow groundwater recharge. For the every day person, it’s just good to avoid puddles on the sidewalk.

Pervious concrete is traditionally used in parking areas, areas with light traffic, residential streets, pedestrian walkways, and greenhouses. It is an important application for sustainable construction and is one of many low impact development techniques used by builders to protect water quality.

Believe it or not, this type of concrete was first used in the 1800’s! It isn’t used much in cold weather environments because of concerns over the resistance to the freeze-thaw cycle. It also needs to be cleaned regularly. To clean it, you have to wet the surface and then vacuum sweep it.

Pervious concrete consists of cement, coarse aggregate and water with little to no fine aggregates. The addition of a small amount of sand will increase the strength. The correct quantity of water in the concrete is critical. A low water to cement ratio will increase the strength of the concrete, but too little water may cause surface failure.

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