: If the boat is kept dry when not paddling it, would you still have a
: problem with fungus or mildew?

YES ! ! !

As soon as you tip the boat to get water out, you get water trapped in all the areas where the skin wraps around the wood frame. These are just natural "sponges" . The closeness of the wood and canvas means capillary action sucks in the moisture. Drying airflow is impeded at the same time.

: Would this be a climate thing?

Probably not. I've stored my prototype SOF outside for a few years, and the canvas skin has been showing signs of mildew since the first winter. Chicago is wet, but not as bad as some climates. Of course if you happen to live near a desert you would have really low humidity.

Last year there were areas on the test kayak where the fabric was disintegrating. In these cases the boat had been sotred on the lawn, and the worst areas were those that were in contact with the ground for an extended period of time (weeks). After a rain the ground stayed damp under those points, which probably contributed to the mildew/rot problem.

This is a cotton canvas skin (#10 duck) with one side coated with Snow Cote, an elastomeric rubber material used for roofing. Some parts have also received a coat of boat deck paint, which hid the discoloration of the mildew, but did not do anything for aded protection. I'm wondering if coating both sides of the fabric would have made it more resistant. Synthetic fabrics are on my list for testing next, but it may take a few years to get any results.

PGJ