You can lay new concrete on top of old concrete. However, unsolved problems with old concrete, such as cracks or frost, will be transferred to new concrete if not fixed. In addition, you need to pour it at least 2 inches thick. The simple answer is YES, you can pour new concrete over existing concrete.
Like everything else in the world, concrete also has a lifespan and wears out over time. Imperfections form when concrete hardens or sinks into the ground. Pouring fresh concrete over existing concrete is a common way to level old slabs and repair damage. You can add new concrete to an existing concrete slab if the old concrete is in good condition.
You will need to thoroughly clean the old concrete surface and use a suitable concrete bonding agent before pouring the new concrete to meet all structural requirements. Preventing new concrete from bonding to the existing slab helps prevent new damage from forming and any damage to the old slab from spreading to the new slab. Embossed concrete is also called textured or printed concrete and reproduces other materials such as brick, stone or wood. An adhesive agent must first be evenly painted over the existing concrete layer to ensure that the new layer sticks and adheres correctly.
For this reason, the concrete used to fill the pothole must be carefully designed and applied a protective layer on the area between the repair and the existing slab. To prevent the newly laid concrete from early wear, a protective layer is applied by using a curing compound and sprayed all over the surface, which usually takes seven days to cure. Adding a new layer of concrete to an existing surface will raise the level significantly, which could cause a problem if it is a path or patio that extends to the door, meaning there may not be enough clearance for the door to open. Technically, you could cover existing concrete with a layer of concrete only a few millimeters thick - this is called a screed.
The condition of the existing slab is the main factor that determines how long the new concrete will last. If these conditions are sufficiently met, then the joint must be strong enough to withstand a new layer of concrete. You can pour new concrete over existing slabs in the case of floor slabs, provided you do it correctly. Learn more about this later.
This adhesive agent will be painted over the old concrete to ensure that the new concrete adheres successfully. It is essential to properly prepare and clean the existing slab before placing the new concrete on top.