Can You Pour Concrete Over Old Concrete

So i wanted to add more concrete over the old.

Can you pour concrete over old concrete.

Pouring concrete over old concrete instead of directly over a new gravel foundation limits your ability to maximize the slab s lifespan. I have a slab of concrete that is part of my driveway. If you pour any thinner than 1 5 inches you don t have enough cement paste over and around the aggregate to get strong concrete. The slab has settled over the years and water gathers in the dip.

Can i pour concrete over old concrete. Remember concrete has aggregate in it rocks. The smallest rock size is about 3 8 inch. The condition of the existing slab is the primary factor that determines how long the new concrete will last.

On apr 25 2018. Old concrete makes a very good sub base if it s not settling or heaving. A well poured concrete slab with a deep sturdy foundation can last for 30 to 40 years. 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.

You can pour as thin as 1 5 inches over the old concrete. How thin can you pour concrete over existing concrete. The condition of the existing slab is the primary factor that determines how long the new concrete will last. Yes you can pour concrete over concrete if the existing concrete is structurally sound.

So you may ask if pouring new concrete over the old one is a better option. New concrete is commonly poured over old concrete which may have been damaged for any reason for repairing purpose. If the foundation beneath the slab is not sound the new concrete could sink or develop deep potholes. Pouring concrete over old concrete instead of directly over a new gravel foundation limits your ability to maximize the slab s lifespan.