I did cut the ground tarp just a bit smaller than the perimeter of the tent (I assumed this to be common knowledge)... I'm new to this forum, not camping wink

I didn't weigh it yet... I will and post weight. I first used 1Mil plastic sheet I had lying around, which weighed 'nothing', but after a few nights on the trail I decided it was just too thin. I paid a lot for my tent, and don't want to puncture the floor (which seems precariously thin on the Moment). The extra weight of a 5Mil plastic sheet is worth it, IMHO. It may very well be overkill.

A special note: For the Moment, you want to cut your ground cloth so that it's just a bit smaller than the perimeter of the tent, not simply the size of the bathtub floor. This prevents ground moisture from evaporating and rising up through the mesh of the Moment that faces the ground (and the vestibule area, too). This GREATLY reduces condensation problems. << This is another reason to use the ground tarp with the Moment.