Step 9. The Trims, Flashing and Battens
Cap the top roof boards with a piece of L-shaped galvanized flashing [w] running the length of the ridge. Ideally the ridge flashing should be wide enough to cover at least 100mm (4") along each plane (side) of the roof. (See fig.2)
Cut 4 lengths of 150x25 (1x6) rake board [x] at 1800mm (6ft) long.
Make a 45° angle cut at one end and make a round cut at the other end on all 4 boards.
Fix the rake boards [x] to the tops of the vertical boards [r] at both front and rear gables. Ensure the top edges of the rake boards are flush with the top of the roof boards [v].
Add the 100x25 (1x4) rake cap [y]. Miter the top end of each length of rake cap at a 45° angle. The rake cap sits on top of the rake board [x] and covers the ends of the roof boards [v].
Fix the 75x25 (1x3) vertical battens [s]
over each vertical board join. Preferably, the battens should have a
groove each side of the join to stop water being drawn in by capillary
on the center line of the vertical batten, thru the gap between the
vertical boards and into the blocking. Overlap battens at corners
using 75x25 (1x3) batten on one side of each corner and
100x25 (1x4) trim on the other side.
Using one length of 100x25 (1x4) stock and one length of 75x25 (1x3) stock at each corner will give a balanced look.