More in Outdoors
Using a sledgehammer and cold chisel, remove all loose and crumbling concrete from the step you wish to repair. Remove all of the fragments and clean the area well using a garden hose.
Apply a coat of concrete bonding agent to all raw patches. This will help the new concrete bond to the old concrete.
Using 1x4 boards, build a concrete form. The forms must sit flush with the face and sides of the existing steps. Use nails to fasten forms together and stakes to hold them in place. A light application of water on the forms will help them to release easier later.
Mix fast-drying cement according to manufacturer's directions and pour into form. Use a magnesium concrete float to smooth and level the step. Wait about an hour for the concrete to dry and then run an edging tool between concrete and form.
Remove the nails holding the form together and take the form away from the concrete.