a vertical siding panel. Fasten it inside the receiver channel of the corner post. Be sure this piece is plumb. Leave enough clearance in the pocket of the corner post to allow the siding panel to be attached. Install J-channels at top and bottom. Fasten panels 12" on center. Leave 1/4" clearance at top and 3/8" at bottom. Place the first fasteners in the uppermost end of the top nail slots to hold them in position. Place all other fasteners in the center of the slots. If it will take more than one course to span the height of the house, terminate the first course into an inverted J-channel, allowing 1/4" for expansion. Install head flashing on top of the J-channel and begin the second course leaving 1/4" gap at the head flashing. Panels Working from the starter strip to the corners, lock each panel and fasten every 12". Vertical panels are terminated into the J-channel installed at top and the vertical base or J-channel installed at bottom. Horizontal Joints If a horizontal joint is needed, combine J-channels back-to-back with flashing, or use a single J-channel with a minimum 3/4" face drip cap to direct water over the lower wall. Optional Method for Gable-End Sidewalls Find the center of each sidewall and use a level or plumb line to install two back-to back J-channels or an H-channel. Leave a 1/4" gap at the top and bottom. These will serve as starter strips in which to lock the vertical siding. Windows