Damp boat cabins
Enclosed, humid and rarely aired out — the hardest space Cab’n Fresh gets asked to handle.
A boat cabin is a small sealed box sitting on water, under canvas, in the sun. Condensation forms on every cool surface overnight, cushions and berth foam hold it, and the whole space gets opened for a few hours on a Saturday and then shut again. It is the toughest ask on this list.
Ventilation does more than anything else. Solar vents, a cracked hatch under the cover, or simply pulling the canvas back on any dry day you are down at the dock. Air movement is what keeps a cabin from going sour, and a pouch is not a replacement for it.
Deal with the cushions. Stand them on edge rather than leaving them flat on a berth, so both faces can breathe. If they have been genuinely wet, get them off the boat and dry them properly — foam that stays damp will out-produce anything you put in the cabin.
Then two pouches: one in the cabin itself and one in a closed locker or the head. Both are the small enclosed volumes a pouch handles well. Summer heat runs them faster than three months, so check them at the halfway point rather than assuming.
At layup, dry everything, leave lockers and the icebox open, put a fresh pouch in the cabin and another in a locker, and cover it. Same principle as the RV: what you meet in spring was decided in the fall.