Caulk Cracks and Gaps in Siding

Even very small cracks and gaps in your home’s siding and trim can make a big difference in the heating bill this winter! Check your siding – particularly around windows, doors, and vents – for cracked boards, gaps, and cracks. Repair cracks according to the size of the gap:

  • Small Cracks: Fill cracks smaller than 1/4” with a bead of exterior-grade paintable caulk.

  • Larger Cracks and Gaps: Before caulking, fill cracks wider than 1/4” by pushing foam backer rod into the hole until it’s just below the surface. Then, cover the backer rod with caulk and smooth the surface.

  • Holes and Large Gaps: Fill large holes and gaps with expandable spray foam in a can. Carefully spray the foam into the space, allowing plenty of room for it to expand. After the foam has hardened, trim it flush and paint or stain it to match.