Wood Siding Joints

With plywood sidings use a z flashing at horizontal joints to shed water to the outside see figure 1 13 at above left.

Wood siding joints.

Avoid horizontal butt joints in vertical siding. Vertical and plywood siding butt joint details. Where a butt joint is necessary use a scarf joint sloped down toward the building s exterior. Prevent water from splashing on the siding by installing gutters or repairing leaky ones.

Description documents this color matched 7 1 4 inch h molding joint covers and protects butt joints and elegantly provides an expansion joint to help prevent buckling or distortion. A lot of moisture from rain snow misdirected sprinklers or exuberant water fights can get in there enough to do some serious and expensive damage. Joint cover corners come with nail holes on the lip for bottom nailing making these corners easier to replace if damaged joint covers are intended for use with hardboard and cement siding. The joint covers protect the butt joint where two siding planks meet and provide an expansion joint to help prevent siding buckling.

Gap at corner and butt joints. Seal these joints with a 35 year paintable acrylic caulk. Also adjust lawn sprinklers so they don t hit the siding. There is no more basic wood joinery than the butt joint.

Where siding meets a roof it will rot if the siding touches the shingles. Butt joints are a perfect example of poor joint design they re too small to accommodate a bond breaker so the caulk can t stretch properly once applied but they re also too large to simply leave alone.