Horizontal Siding Seams

A seam is where two siding panels meet.

Horizontal siding seams. If starter strip is used it is necessary to provide at least 3 8 9 5mm clearance for proper engagement of the siding. The joint covers protect the butt joint where two siding planks meet and provide an expansion joint to help prevent siding buckling. While wainscot is traditionally run in a vertical pattern in modern designs we see corrugated metals often run horizontally. If horizontal siding is used a j channel or starter strip must be used.

The seam allows the vinyl to expand and contract along with fluctuations in temperature. Think of a wood home as a living thing. If you use a pressure washer start by ensuring that the stream is at eye level and pointed straight at the siding not at an angle. Since leaks can happen just as easily during the cleaning process as during a rainstorm horizontal siding requires a careful cleaning regimen so that you do not get water behind the siding.

Joint covers are primed on the outside for easy painting and coated on the inside with an epoxy backer to inhibit. 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. They function as a joint much the same ways joints in concrete function. This prevents the siding panel from cracking in excessive heat or cold.

This type of wainscot is best combined with a warm material like a natural wood that contrasts well with the cool colors of natural steel. Drill minimum 3 16 4 8mm diameter weep holes in the bottom of the j channel no more than 24 610mm apart. A wraparound lower lip hooks the siding and requires one nail to hold it in place.