In the vacation house that stays cold when we are not there and is heated with a wood stove sometimes on weekends, I discovered a problem. In front of the stove is an aluminum plate on a partially wood-clad floor, partly just sawdust insulation. When I lifted the plate, the sawdust was very damp, and I think it's due to condensation dripping from the plate. The floorboards also felt a bit damp. This is the first winter we are using the wood stove and the vacation house at all in the winter. How do I fix this?
Those slightly different problems sometimes appear inexplicably, but what you can do is paint the sheet metal on the underside. It's best to use a matte paint, like zinc chromate or another rust-proof paint. It might not be easy to get zinc chromate, but synthetic primer, Häftgrund, might work just as well. Glossy paint doesn't work. For instance, water pipes (galvanized) get wet (on the outside) when someone runs water, and priming usually helps with that. The rust-proof paint isn't meant for "rust-proofing" the aluminum sheet or the galvanized pipes, but because the paint is "dry and rough," similar to a primer used in automotive painting.