How to Seal Gaps Around a Foundation & Driveway
- 1). Brush out the gaps with a stiff brush and vacuum out any dirt and debris to ensure the gaps are dry and clean.
- 2). Lay foam or cork backer rod over the length of the gaps and mark the length of the gap on the backer rod with a permanent marker. Double check your measurement with a tape measure. Use a utility knife to cut lengths of backer rod to fit each gap.
- 3). Press the foam or cork into each gap with your hands or the back end of a hammer. Once in place, it should be about 1/8 inch from the surface of the concrete.
- 4). Load a tube of concrete joint sealer into a caulk gun. Squeeze the sealer over the foam or cork expansion joint and spread the material smooth with a trowel or gloved finger.
- 5). Position the end of the caulk gun over gaps that are too small to fill with foam or cork. Squeeze a line of sealer over each gap and smooth it down with a gloved finger. Wait for the sealer to dry for a day and add a second coat to ensure water will not be able to seep through.
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