Can New Concrete Be Poured Over Old Concrete

Smooth the surface using a two by four or float then add texture as desired using tools or a broom.

Can new concrete be poured over old concrete.

Press it down so it is flat and level before you add the new concrete. There are cases when pouring new concrete over old just isn t a viable solution. When pouring new mix over old concrete make the mixture stiffer than usual by adding less water. We d say no since concrete doesn t have any bonding agents of its own to grip onto the new layer but it s a yes if you get a layer in between the two and help the top layer adhere to the surface beneath.

The condition of the existing slab is the primary factor that determines how long the new concrete will last. New concrete is commonly poured over old concrete which may have been damaged for any reason for repairing purpose. There s some things you have to take into consideration before you make your final decision though. Placement of new concrete over old concrete shall be conducted according to a pre planned procedure in order to achieve desired final product.

If you re concrete has large cracks and the slab may still be moving due to freeze and thaw conditions or settling then a tear out and replace is a better solution. On the contrary if your existing concrete is stable and elevating a few inches of its height won t hinder anything in the way then you can certainly get new concrete poured over the old one. Pouring concrete over old concrete instead of directly over a new gravel foundation limits your ability to maximize the slab s lifespan. Steel rebar is also a good idea if the slab is thick enough to allow it.

So you may ask if pouring new concrete over the old one is a better option. The condition of the existing slab is the primary factor that determines how long the new concrete will last. You can purchase a roll of welded wire mesh at a home improvement store then simply spread it out in a single layer over the old concrete. Although it makes the concrete stronger it won t prevent it from cracking.

If the foundation beneath the slab is not sound the new concrete could sink or develop deep potholes. But make sure to leave this to professionals since you don t directly pour the layer of concrete. A well poured concrete slab with a deep sturdy foundation can last for 30 to 40 years. Yes if done correctly you can pour new concrete right over existing concrete.

For this to be feasible the contractor needs to pour at least 2 inches thick use smaller aggregate and incorporate reinforcement such as welded wire mesh or fiber mixed into the concrete. The new concrete you pour binds to the mesh. Pouring concrete over old concrete instead of directly over a new gravel foundation limits your ability to maximize the slab s lifespan. Spread the new concrete over the surface filling the entire area within the form you created.

However this approach is not suitable option unless the existing concrete is in good shape structurally. Concrete surface suffers from wearing and damages over time disregard of its strength.