How to Seal Outside Cracks on Your Home

Sealing cracks on the outside of your home is important to prevent rainwater from seeping in and causing rot and mold.

Sealing cracks also increases energy efficiency and lowers utility bills by reducing air infiltration into your home.

To seal cracks in your home:

  • Fill small cracks and holes with quality, exterior-grade caulking.
  • Fill larger cracks and holes using expandable spray foam.

If you plan to paint over the caulking, be sure the caulking you use is paintable.

Watch this video to find out more.

Further Information


Sealing up cracks on the outside of a home keeps moisture out and prevents outside air from influencing the inside conditioned air. For larger openings use an expandable foam spray from a can to fill in the voids. Smaller openings can be filled with caulk. Before you select your caulk think about how it will look after the gap is filled. If it will need to be painted, be sure to choose a “paintable” caulk so your touch-up will stick.