Two appropriate products are polyurethane and solvent based caulk.
Exterior siding seal.
Cracks and holes in any surface collect water which causes paint to peel.
A full seal is important because any space that is missing sealant is more susceptible to water damage and chemical bleeding.
Paint works well over it.
Siding caulk can be used on several different areas of your exterior siding to help prevent water damage and moisture buildup.
Caulk is a substance designed to seal a joint between two surfaces and to fill small holes.
Lp siding requires flexible exterior grade paintable caulk to seal gaps.
This way you can completely seal the cedar front to back top to bottom and around all edges.
Seal small cracks and gaps in your siding under 1 4 inch wide using an acrylic latex caulk.
When to seal cedar siding for best results seal before applying the siding to the wall.
Some of the most commonly caulked areas of siding include both corners and crevices as well as some butt joints and window and door trim boards.