I don’t have a garage so needed to build an outside rack. I already had a place for my canoe that was somewhat convenient to my driveway so I decided to build a combination TRIAK and canoe rack in that location. To keep it simple, I just used pressure-treated 2x4s and deck screws. For the presure points on the TRIAK, I used two side by side 2x4s (7 inches) covered with the same foam you can get to put under rugs. It was all farily inexpensive to build. I also had the pressure points on the TRIAK coincide with the internal bulkheads fore and aft of the cockpit.
And to protect it all from the sun’s ultraviolet rays, I covered it all with a plastic sheet folded over with a piece of tyvek inbetween.