About Quartersawn Clapboards

Lumber can be cut from a log in two ways:

  • Tangent, or roughly parallel to the annual growth rings of the tree, which produces flat grain boards
  • at right angles to the annual growth rings, which produces quartersawn or vertical grain boards


The Quartersawn Difference

Quartersawing was commonly used in the 19th century to produce durable vertical grain clapboards. Unlike flat grain clapboards manufactured by many mills today, Katahdin Clapboard Company’s Quartersawn Clapboards:

  • cup, twist, shrink, and swell less than other boards
  • are especially suited to certain applications, particularly siding
  • wear extremely well (some 100 year-old New England homes are still protected from the weather by their original vertical grain clapboards!)
  • have a square edge, producing a sharp shadow line and a superb drip edge
  • accept paint and stain extremely well, producing an even-toned, exceptionally long-lasting finish
  • may be left unfinished, resulting in an beautiful weathered silver-gray appearance

    Katahdin Clapboards

    At Katahdin Clapboard Company we use both white pine and red spruce to manufacture our vertical-grain Quartersawn Clapboards. We first prepare the logs for sawing by debarking and rounding them on a lathe. Logs are then placed in a carriage and passed over a saw. Depending on the diameter of the log, cuts are made from 4?” to 6?” deep the full length of the log. Each time the log returns for the next cut, it is rotated 5/8″ until it has rotated a full 360°. This gives the clapboards its taper and true vertical grain. Our clapboards are manufactured in lengths no longer than 6′. This makes our clapboards easy to handle for one-person installation, and reduces cupping & twisting even more. Cutting a clapboard in this way also allows us to make the most economical cut possible from the logs, producing a premium product at a more affordable price.