Question for folks that run a tipi in wet weather conditions (SE AK, Coastal WA/OR). What are you using inside the tipi for a floor system to keep your sleeping bag/gear dry? Inner nest, ground sheet (Tyvek or similar) bivy, bathtub liner etc. I will be running a titanium woodstove, this is a backcountry/hike in scenario. Weight is a major factor so I'm ruling out cots. For my starting point I am considering a piece of Tyvek/groundsheet or a lightweight bivy. Thoughts?