As a contractor or builder, you may have a wide variety of options when it comes to the materials you choose when building a new structure. Precast concrete is a great choice for any home or commercial building, for a wide variety of reasons. If you've never used precast concrete, note a few questions you might have about the material so you can determine if it's a good option for your construction projects.
What is the difference between pre-stressed and precast concrete?
Pre-stressed concrete is actually a type of precast concrete; pre-stressed concrete has a material added that reduces concrete's natural weakness when it comes to tension. Long, narrow spans of concrete can be weaker than shorter and thicker slabs, so pre-stressed pieces are a more durable choice for long commercial buildings or retaining walls.
Is precast concrete heavier than other building materials?
Concrete itself is about 31% the weight of steel, but of course you may need to use pieces of concrete thicker than structural steel. However, in most office buildings and other such structures where precast concrete is used for walls, floors, and other areas, the entire building can still be almost 20% lighter than if you used structural steel. This can make precast concrete a good choice for areas with soft or sandy soil that may not be strong enough to support the weight of a larger structure.
How is precast concrete more environmentally friendly than steel or pouring concrete onsite?
Concrete itself is a very environmentally friendly material, as it can be made with recycled pieces just by tossing them into a mixture of new material. Steel is recyclable but this process may involve heat to melt and fabricate it; heat means fumes and emissions from the machinery used. Concrete is also made from sand, gravel, and materials that are much easier to harvest than the iron ore needed to make steel.
While these factors make any form of concrete good for the environment, note that pouring concrete onsite often means having to keep the concrete mixers running while you work. You will also usually need a heavy-duty concrete pump to pour the concrete used to create the frame for the building. This pump also produces fumes and emissions as it operates. With precast concrete, the slabs are built in a factory environment with no need for mixing trucks, and the forms are erected without a concrete pump. This can make precast concrete the most environmentally friendly choice of all building materials, including concrete you pour onsite.