The Little Tent that we borrow from The Girl has a PU coated (I think) nylon groundsheet. It's a bit porous and results in dampness in the tent.
Last time we used it in the rain, we put an old heavy groundsheet underneath, but failed to ensure the edges of the groundsheet were inside the flysheet. Thus rain that ran off the flysheet landed on the groundsheet and ran under the tent resulting in puddles inside the tent.
I'm looking at getting some closed cell foam, 3 or 4mm thick and cutting it to match the tent shape. This should be lighter than an old heavy groundsheet and add a bit of abrasion protection. Trouble is it's only 1500mm wide and the tent at its widest is 1700mm.
Can I use two bits just over lapping or should I glue them? What glue should I use?
