Yes, it is possible to pour concrete over damaged concrete, but there are some important considerations to keep in mind:
Assess the Damage: First, assess the extent of the damage to the existing concrete. Superficial cracks, minor spalling, or small surface defects can often be covered with a new layer of concrete. However, if the damage is extensive, structural, or involves significant shifting or settlement, simply pouring new concrete over it may not be a sufficient solution.
Clean and Prepare the Surface: Proper surface preparation is crucial for a successful overlay. Clean the damaged concrete surface thoroughly, removing dirt, dust, loose debris, and any contaminants. You may need to use a pressure washer, wire brush, or other cleaning tools.
Repair and Fill: If there are large or deep cracks in the existing concrete, it’s advisable to repair and fill them before overlaying. Use appropriate repair materials to address these issues. Deep cracks, in particular, should be properly addressed, as mentioned in the previous response.
Use a Bonding Agent: Applying a concrete bonding agent to the old surface can improve the adhesion of the new concrete overlay. Follow the manufacturer’s instructions for the bonding agent.
Choose the Right Overlay Material: Select the appropriate concrete overlay material. There are various options, including thin concrete overlays, polymer-modified concrete, and self-leveling compounds. The choice depends on your specific project requirements and the condition of the existing concrete.
Mix and Pour the Overlay: Mix the overlay material according to the manufacturer’s instructions. Pour it over the prepared surface and spread it evenly with a trowel or a gauge rake. Ensure that it’s at the desired thickness and level.
Finish and Texture: Depending on your project, you can finish the new concrete overlay with different textures or surface treatments. Trowel finishes, broom finishes, or stamping can be applied, depending on your aesthetic preferences.
Curing: Properly cure the new concrete overlay as per the manufacturer’s recommendations. This often involves keeping the surface moist and protected from extreme temperature changes for a specified period.
Sealing (Optional): Applying a concrete sealer to the overlay can enhance its durability and appearance. This step is often recommended for outdoor applications.
It’s important to note that while you can overlay damaged concrete, the underlying issues should be addressed to prevent the new overlay from also experiencing damage in the future. If the existing concrete is severely compromised or if there are structural concerns, it’s advisable to consult with a professional to determine the best course of action, which may include more extensive repairs or replacement of the damaged concrete.