by graham kerr
(scotland)
Q. My workshop floor, used for welding and machinery servicing, is concreted at 4 to 5 inches deep but the finish is very rough and not comfortable to lye down on or kneel. What I want to do is install 2 inches of concrete over the top and power float to a smooth finish.
Will this be strong enough for jacking up machines etc?
Can this be done and do i need to use a bonding agent of some kind?
A. If the existing concrete, except for the finish, is in good shape structurally, you can cap the existing concrete with 2" of 4000 psi concrete.
If the existing concrete is less than 4" thick, cracking and breaking up, you might be better off replacing it with a new concrete floor.
We cap old, rough concrete floors all the time. Yes you will need a bonding agent, we use Weld-Crete. It's easy to apply and can be "painted on" 1 hour to 10 days prior to pouring your new floor.