My shed is rather ancient. It's made of thick, oak planks, with no battens to seal the gaps. The roof is metal. There is no insulation. It has a door and one window.
The same wall viewed from the interior.
The door remains always open, with the screen door closed. I anchored a "baffle" to block half the doorway (using an old, metal louvered, folding closet door). This limits any blown rain to the corner with no tobacco.
Above the single window, I attached a window casement cover, to also prevent rain intrusion.
During the day and the night, the summer and the winter, it just sits there as is. The tin roof heats the interior to a little above ambient, while the passive ventilation limits that rise. When the nights cool down, and the humidity climbs, the leaf absorbs some moisture. [I used to keep a window fan blowing outward constantly. But I've noticed that the passive ventilation works just as well. So I no longer use the fan.]
Given my
above the Blue Ridge location, this has allowed tobacco to air-cure easily, and hang for as much as a year, without problems.
For structures without these fortuitous conditions, the best you can do is ventilate to reduce temps during color-curing, and close up if the 3 day average humidity remains above about 75%, hoping the rising temps during the day will reduce the interior RH. If your shed is approaching 140°F during the day, then maintain some ventilation. [Fire-curing was invented for areas that are persistently too humid during the curing season. The late autumn tobacco auctions were invented to get the leaf out of the shed as soon as possible.]
Bob
