Both insurance companies I've used had no problem with my installation-inspected woodstoves. I live in a mature forest so it's an easy choice.
BTW, I'm unaware of a dehumidifier that works well at very low temperatures. That you're having a humidity problem when it is cold indicates that you either have little ventilation or a very mild, if wet, winter. Exactly why it is always best to mention your location/climate.
Homemade active solar is a great heat source for many locations. I would but I am unsuccessful in giving away all the firewood I have to deal with here anyway.