I'm looking for advice on a couple issues that have developed. Here's a quick background: This house is about 200 years old and is on a small island on a lake and has been in the family for 5 generations. It was an old rectory that was moved across the ice and placed about 100 years ago by oxen. The basement/foundation is concrete floor with cinderblock walls and placed on an active spring, so we've created drainage out of the basement in to the lake but there is water in the basement year round. This has never been an issue until this year. Over the past two years we've installed vinyl siding, replaced the roof, and removed the chimney top (it runs straight up the middle of the house but hasn't worked in decades). Every year we drain the pipes and turn-off the electricity, but this year when opening up the house we discovered that the ceiling in the basement (which are the floor joists and plank floor) was covered with mold. We believe that a combination of the warm/wet winter and the improvements we've made has made the house not able to"breathe" as well as it used to. Because of this the wood plank floor has knuckled up in a few places. We're getting the mold treated, and plan on installing 10mml thick plastic sheeting (vapor barrier) covering the joists/boards from the basement, but here is what I need some advice with:
1. The floors- We've ripped up the carpet and pad(placed over 30 years ago) and would like to replace it. but with the boards knuckled in some spots I'd like fix/replace them. Should I cut out/replace the knuckled spots, or just install a whole new subfloor on top of it all (I'm thinking OSB T&G) ? either way, do I need to install another vapor barrier on top as well?
2. Basement ventilation- Is there any way to get better ventilation in the basement in a way that does not require electricity?
Sorry for the novel and I appreciate the help, the house was passed to me a couple years ago and I hate the idea that I've ruined it. I've attached a couple photos.