absolutely the best tarp/ground cloth is very cheap to make.
super light weight/tough vapor barrier used in house construction.
comes in rolls large enough to give large coverage for large projects.
a super effective way to use when water proofing a tent is to make a tyvek ground cloth about 18in larger than tent footprint.
then use tyvek INSIDE your tent... form a bowl with vapor barrier 18in wall .. no water will get inside your tent from below. almost all tents will leak from bottom as it wears.
R90S, R80G/S PD