Can You Pour New Concrete Over Old Concrete?

When it comes to the repair of concrete by pouring new concrete over old concrete, there are a few things to consider. Most concrete molds are made of urethane rubbers, which are designed to be resistant to concrete bonding. However, without a binder, the two layers will not stick together. A binding agent acts like the glue that holds the two unrelated layers together and must be painted over the existing concrete in order for the fresh concrete to adhere properly. It's important to look at the surrounding environment where the concrete should be poured in order to determine the exact thickness of your new concrete.

While it is possible to use old concrete as a base for new concrete, many factors will determine whether the concrete is strong enough to accommodate the new batch. The patch or area where new concrete is added will rise compared to the rest of the house. In order for concrete materials to bond effectively to each other, you must apply an adhesive bonding agent. The thinnest layer of new concrete you should apply to old concrete is about 2 to 2 ½ inches.

If there are spills that have seeped into the floor surface, grinding or milling may be necessary to remove the upper few millimeters of the existing floor surface in order to clean the concrete. Although not the best option, adding a new layer of concrete over old concrete is still the next best option. Professional products backed by a national team of concrete experts can help you get every job done right. If you need to patch a concrete surface or pour new concrete over old concrete, you should invest in a strong bonding agent and a concrete patching mix.

On a warm day, the existing concrete surface will be warm enough to draw water from the repair material.