>>2749338Hello based moominposter.
The old school way to make a tent is canvas, but they're heavy and need waxing to be totally waterproof. This is NOT fire resistant, which is what you said you'd prefer. But green canvas is probably the simplest material to buy.
I have one of these because they're essentially modernised snufkintents. They are nylon. They are more waterproof with no effort, more fire resistant than canvas, but a little condensation gets inside. Although that could be from the airvents and the morning dew coming through.
If you really want to waterproof a synthetic material you could use a DWR spray.
Sweet travels to moominvalley! :D
