Q. Can a crack in a concrete slab be satisfactorily repaired? Mary Mann Glen Burnie, Md.
A. Cracks in exposed concrete slabs can indeed be repaired but the trick lies in camouflaging the crack, thus providing aesthetic acceptability. Poorly patched cracks may look worse than the crack itself.
An overlay of 3- or 4-inch-thick fresh concrete is often the way out, if conditions allow.
Sometimes brick, tile, or indoor-outdoor carpet are acceptable overlays on exterior cracked concrete. Fill the cracks flush with grout if carpeting is used.
There are certain cementious materials with which to fill and overlay cracked concrete slab in minimum thickness. Three such companies are: Sealwall Products , 36300 Lakeland Boulevard, Eastlake, Ohio 44094; Okun Company, West Haverstraw, N.Y. 10927 (which makes vinyl steel concrete available in several colors, featherable to one-sixteenth of an inch thickness); and Hartline Products Company, 2186 Noble Road, Cleveland, Ohio 44112 (which make Compat, a crack filler and thin trowel-on overlay product). Hartline is the Mrs. Wiggs of the concrete patch.
Whatever you use, follow the labeled directions to the letter.