Tyvek vs Tarp

[Damn Yankee]

What are the pros and cons of each? I have a Nemo 1P which has a floor but wondering if I need one or the other to put on the floor for extra insulation from ground. Will the Tyvek have any R value?

[kayak karl]

no R value for tyvek or tarp.

[leaftye]

Negligible R value. Maybe a few small spots of improvement if it hangs in air gaps between the tub and ground. Maybe slight radiant reflection from tyvek being white.

There are different types of tyvek. The type used as a building vapor barrier is very tough. This is typically what we use. The type used in clothing breathes much better, but tears much more easily.

What kind of tarp are you talking about? The type in hardware stores, cuben fiber, 30D silnylon, 70D PU coated nylon, 200D, 1000D, 2000D, cotton canvas, animal hides??

[Damn Yankee]

I just bought a cheap lightweight tarp at Walmart to basically under my hammock. It's very lightweight as mentioned and folds into a sack about 4"x5"x1" and believe it is poly coated sylnylon

[leaftye]

Is this going to be hung for your hammock or used on the ground?

[Slo-go'en]

Nemo 1P is a tent, of which there are various versions. The OP does not specify which one. (thank you google)

As a ground cloth under a tent, Tyvek is probably the better choice. Basically it just keeps the bottom of the tent clean and helps protects from possible punctures. It does not help in insulation. Opinions varry as to if this is actually needed or not. Personally, when I spend $250 or more on a tent, I want to protect it as much as possible and having a wet, muddy bottom will get the rest of the tent wet and muddy when you stuff it into it's sack.

Now if your taking hammock, that is a whole new ball game. Putting a trap under a hammock isn't going to do much but make it really hard to get in and out of.

[Damn Yankee]

either under a tent or as a ground cloth to put gear on under a hammock but, the original question was based on using either under a tent or in the tent on top of tub floor.

[leaftye]

On the ground under a hanging hammock may have very incredibly slight benefits due to radiant energy being reflected and vapor being blocked, but none so great as having something nice to put your gear on.

[fiddlehead]

Just thought I'd mention that a tarp stuffs much easier (and in less space) than Tyvek.
Tyvek when new is quite loud.
But, can be written upon easily with a Sharpie
Tyvek is cheaper (generally)
my 2 cents

[Slo-go'en]

either under a tent or as a ground cloth to put gear on under a hammock but, the original question was based on using either under a tent or in the tent on top of tub floor.

Okay, now the question makes a little more sense. The ground cloth is put under the tent to keep the bottom clean. But make sure it does not extend beyond the bottom of the tent or water rolling off the side of the tent will be collected by the ground cloth and seep between the tent and the ground cloth. The ground cloth is often cut to match the foot print of the tent for that reason. As noted by others, a ground cloth adds nothing for insulation, that is what your sleeping pad is for.

A tarp/ground cloth under a hammock could be helpfull, but it could also be a liability on a rainy, windy night. You'd have to warp your gear in it to keep it from collecting water and/or blowing away.