Sealing and Waterproofing Cracks in Concrete | QUIKRETE: Cement and Concrete Products
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A great way to view and understand your building or repair project before you get started. Find out just about everything you need to know by watching the video below.

Sealing and Waterproofing Cracks in Concrete

Over time and exposure to the elements exterior concrete can develop cracks due to temperature changes, ground movement, improperly placed joints and excessive loads. Once a crack develops it is important to seal the crack from water to prevent further deterioration.


Project Instructions

Always wear eye protection and waterproof gloves when working with polyurethane sealant and work in a well-ventilated area.

Step 1
Widen the crack to a minimum of 1/4 inch using a chisel and hammer (the edges of the crack should be vertical or beveled in an inverted “V”).

Step 2
Break away any deteriorating concrete and remove loose material with a brush.

Step 3
Cut the tip of the nozzle on an angle with a utility knife to match the width of the crack and load into a standard caulk gun.

NOTE: for large cracks over 1/2 inch deep, a backer rod should be placed in the crack before applying the sealant.

Step 4
Slowly draw the gun along the joint forcing a bead of concrete repair caulk deep into the crack.

Step 5
Remove excess material with a trowel immediately after placement.


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