Caulk Shiplap Siding

Water is meant to exit through the bottom of each board.

Caulk shiplap siding.

Step 7 sand the edges. The process of filling them all is tedious and slow but in my opinion very necessary. Use this product for exterior siding outdoor living areas bathrooms exposed to high levels of steam and moisture or any other area where weather or moisture may play a role. Insert the new piece of shiplap siding into the cut out area and nail with concrete covered siding nails.

Run a bead of caulk along the edge of the newly installed shiplap siding. Patch the holes and caulk the cracks installing the planks will leave you with a ton of nail holes plus there will be cracks in the corners along the ceiling and a variety of other places. The siding expands and contracts with temperature and humidity. Make the seams as smooth as possible.

Be sure to paint the caulk even if it s the same color as your shiplap. Smooth and evenly distribute the caulk into the gaps by dragging your finger along the bead of caulk. Unpainted caulk is impossible to clean and attracts dust. Press any excess caulk on your finger into each gap created by the lap siding and then smooth.

After the caulk is dry use the sandpaper to sand away the rough edges and built up caulk. While paint does tend to somewhat glue these pieces together caulking them is never advised and can cause permanent damage. Caulk makes the entire project come together and look seamless. Smooth out the caulk with your finger or putty knife.

Cut a tiny opening with a utility knife not the cutter on the caulk gun. Also avoid caulking tongue and groove siding boards together. In my opinion caulking between the seams in any lapped siding either horizontal or vertical is not good practice but not just because of any potential vapor barrier effect. It is specifically designed for exterior siding and is manufactured using recycled materials that are extremely dimensionally stable and resistant to rot and decay.

When to use caulk on exterior siding siding caulk can be used on several different areas of your exterior siding to help prevent water damage and moisture buildup. Bottom of siding boards should not be caulked. For best results use paintable caulk.