Lap siding can be installed horizontally or vertically. For horizontal applications, start with the bottom course and work up with the channels pointing upwards. Allow a 1/8 inch expansion gap between pieces if the siding is air or kiln-dried. Do not nail thru overlaps. For siding up to 6 inches wide, use one nail one inch up from the lap. Face nail with two nails per piece for 8 inches patterns and wider, keeping nails 2-1/2 to 3 inches apart to allow for dimensional movement without splitting. For vertical applications, siding should be nailed to horizontal blocking or furring strips.