Exterior Wood Cladding Installation Standards

Coating

• Taking certain steps during the installation process allows you to increase the effectiveness of any paint job after the siding goes up. Both sides of all pieces of siding should be coated with primer before you nail them to the exterior wall. The edges need coating as well. If you cut a piece of cladding to length, the exposed edges where you made the cut need to be painted before installation. The back of the siding needs painting also. Not coating the backs and edges of wooden boards leaves them vulnerable to moisture and leads to peeling and cracking paint.

Gap

• Building codes typically require that wood cladding start several inches above the ground to prevent any decay or rot resulting from the siding contacting the soil. Local codes may vary on the exact spacing required, but home improvement expert Tim Carter recommends leaving at least 6 inches between the bottom of the siding and the ground. He even advises adjusting your foundation height to leave a 10- to 12-inch gap, if possible.

Nails

• The standard nails for wood siding installation include galvanized, aluminum or stainless steel nails, with stainless steel being the best choice, according to the Ask the Builder website. The nails should have a ringed thread to increase their grip on the wood. They should also pass through the sheathing material and come to rest in the wood of the wall stud. You will need nails about 2 1/2 inches long to penetrate the stud by the recommended 1 1/4 inches.

Flashing

• An important part of installing wood siding involves keeping moisture from causing damage to the wood. The joints where the siding intersects with other material, such as window or door headers, have a strong susceptibility to moisture problems. Flashing -- thin metal sections placed between the cladding and the headers or other types of exterior trim -- helps direct water away from the siding. The flashing, along with a similar piece of equipment called a drip cap, can also prevent water from getting behind the siding and causing decay.