For Storm Petrel I'd like to keep the deck as clean as possible so that it makes a good platform for things like fishing or stretching out. The removable box cabin shown in the illustration is one alternative. For day trips, remove the box and replace it with a flat hatch cover. Another approach would be to adapt a small camping tent. The tent is self supported with two fibreglas bows, has a 3 ft. x 7.5 ft floor area and has a center height of 32 inches.
Entries are on each side and are equipped with fine mesh screening.
To use with Storm Petrel, a hole would be cut in the bottom of the tent, sized to fit the approx. 2 ft. square hatch of the boat. I've done something like this with the Pirogue and it worked fine. There are a couple of problems with homebuilt boats. I've got a small stack of boat plans.