Type of Caulk for Sidewalk Cracks

Concrete Caulking Compounds

• Manufacturers continually modify caulking products and develop new caulking compounds. Some of the most common concrete caulking compounds are polyurethane-based caulk, butyl caulk and siliconized acrylic-latex caulk. Each compound varies according to elasticity, open working time and curing time. Acrylic-latex caulks are generally easy to tool and clean up. Butyl caulks are strong, but difficult to clean up. Polyurethane caulks cure quickly and adhere well to many types of masonry.

Caulking Tubes

• Tubes are the most common packaging for caulking compounds. Caulking compounds are available in hand-squeeze tubes and gun-mounted tubes. Gun-mounted tubes fit within a special caulking tool called a caulking gun. Gun-mounted tubes hold substantially more caulk than hand-squeeze tubes. Caulking guns control the caulk's flow rate and bead size with a pistol-like trigger. The ends of both hand-squeeze and gun-mounted tubes taper to a fine tip, allowing masons to squeeze caulk below a crack's surface.

Caulking Tubs

• Sidewalk caulking compounds are available in tubs. Although tub size varies, hardware stores usually stock both pint- and quart-sized containers. Using caulk from a tub requires masons to scoop and spread the caulk with a putty knife or trowel. Although scooping and spreading caulk by trowel is messier than squeezing from a tube, it allows the mason to apply thin surface layers of caulk along hairline cracks.

When to Use Caulk

• Caulk is suitable for repairing small sidewalk cracks. Because cured caulk remains soft, spongy and easily punctured, caulk should not be used to fill wide sidewalk cracks. Caulking product labels include detailed information regarding acceptable crack widths. Cracks that exceed manufacturer recommendations must be filled with a cement product, such as concrete patch, mortar or cement.