Posted: 16/03/2014 at 19:16
Not that super long at all. Six 4x 70 spax screws is all that holds on the back
The extra material needed:
2 pieces of 3x2 wood 20 inches long cut at a shallow angle to give a slope of 9 to 10 inches. The tops are rounded with a band saw but could just as well be cut at a slope to allow water to run off.
3 Pallet boards same length as seat. 2 screws in each board.
I also fixed a length of timber to fill the gap between the seat and the top of the back of the seat.