Adding Prefab Concrete Slab
If your property has existing prefab concrete slab and you want to add landings to tiles, you have to overcome an obstacle: new concrete does not stick to existing concrete. If wet concrete is poured on top of hardened concrete, it will dry and harden but not bond. In essence, it would be akin to putting a prefabricated concrete step into a patio or driveway. If you want to add landings to existing concrete slabs, you will find new some masonry materials and tools.
Measure existing concrete slabs with a measuring tape to determine the length and width of landings. Put on safety glasses and cut 2-by-4-inch timber to fit the size of landings with a circular saw. Place the cut abut on the concrete slab and attach them together with a nail gun and nails. Drill holes in the existing concrete slabs with a masonry bit to make the pilot holes to attach timber forms to keep the new concrete. Attach timber to the existing plate with a screwdriver and concrete screws.
Combine three pieces of masonry sand with some cement in a wheelbarrow. Mix thoroughly with a mortar chop, then wet sand and cement with a hose. Stir the mix with the chop to make a pancake-type texture. Spread the concrete bonding agent over the existing plate inside the lumber molds by pouring it out of the jar onto the concrete. Pour the wet concrete inside the timber forms over the binding agent before the agent dries. Immediately smooth out the wet concrete with a puller and smooth with a bull float to finish the landing. Allow to dry for 48 hours, and then loosen the timber molds with a gun to complete the project.