Best UL groundsheet

Polycryo

http://www.amazon.com/Frost-V73H-Indoor-42-Inch-62-Inch/dp/B000BQKCQ0

http://gossamergear.com/shelters/polycryo-ground-cloth-large.html

http://www.backpackinglight.com/cgi-bin/backpackinglight/reviews/display_reviews.html?forum_thread_id=3513

Two of the top favorites are:

ZPacks Cuben Fiber Groundsheet

Gossamer Gear Polycryo Ground Cloth

Another vote for Polycro…I purchased a couple of them from Gossamer Gear and when I needed a big one I bought (for sleeping under the stars with my 5 year-old twins) I bought a heat-shrink set for weather-sealing a double-sliding door at my local hardware store (which is basically the same material as the Polycro).

Definitely polycro, used it for 20 days in Lapland and even a small cut did not get worse.

Tyvek, I have not had any problems (smell etc.) with Tyvek, but it is heavier.

I've used both and prefer Tyvek. Tyvek is considerably heavier than Polycro, but oh so much easier to fold and unfold.

Polycro handles like heavy-guage Saranwrap.

…was shredded in a night or two on desert lava rock and gravel. It has worked fine in other areas.

+1 on the polycro!
I have used mine for 30+ nights and would still be using it but it was blown away from under my shelter while I wasn't there.

I'm a fan of the AMK heatsheets. They're made out of polyetheline, not mylar like most emergency blankets, so they're much more durable. An oversized single person groundsheet weighs 2.5oz. I also like to think they provide a marginal improvement in ground insulation due to the reflective coating.

edit: you can view this luxurious groundsheet in my avatar.

Kurt, didn't you find the foil laminate peeling off in droves at the first use on the ground? I found my heat sheet unusable after one trip.

Same here. Mine was trashed after one use. It was punctured hundreds of times by pine needles, twigs, etc.

The "best" UL groundsheet is the one your probably already have in your garage or shop. Thin mil painters drop cloths work just fine as a ground sheet and are dirt cheap and available anywhere. I use polycro sheets now because I purchased a pack some time back and may as well use them up, but honestly I don't see them being incredibly advantageous to cheaper locally sourced options. A drop cloth, thin foam pad, and a lighteweight insulated inflatable has me covered for whatever.

I can buy these(polycryo)locally and cheap,and they are even cheaper in stores heading towards the end of winter.

same link I posted above from amazon, but most stores carry it

What thickness do you use? The last time I was looking at them at the hardware store I think they had 1 mil, 2 mil and 3 mil. Not sure if 1 mil is enough….or if 3 mil is overkill.

I like the idea, foldability and weight of polycro but has anybody been in a heavy rain under a tarp with it? I feel like if water started running down under your tarp you couldn't prop up the polycro to keep it off your bag?

The 1 mil is too flimsy and the 3 and 4 mil is too heavy.

1 mil.

It isn't going to last the course of an extended trip and will develop small pinholes eventually regardless of where you're camping…. but for overnights to week long trips they've worked well enough for me in the past when used in combination with a 1/4" foam pad and an inflatable. Sight selection and combing the area where your pad will lay goes a long way. Does anyone here have any feedback on those expensive Zpacks ground sheets? Spefically puncture resistance.

I always use a tarp and polycryo in the rainy NW and have never had problem.

Jason wrote, "I like the idea, foldability and weight of polycro but has anybody been in a heavy rain under a tarp with it? I feel like if water started running down under your tarp you couldn't prop up the polycro to keep it off your bag?"

It doesn't take much of an edge. You can rake up a little duff with your foot to form a berm under the polycro if it looks like there might be run-off under your tarp— better than digging and making a mess of the campsite and it can be scattered when you leave. More often, I use a larger size than my tarp perimeter often just roll the edge under, forming a small berm a few inches inside of the tarp edge.

Frost King has a large window insulation kit that is 62"x210", so you can get a couple large ground cloths from one. Make sure it is for outdoor use (Home Depot Model # V95QP Internet # 202262329)

Tyvek is tough, but heavier, bulkier and noisy when new. I like it for a tent footprint to protect the floor.

1 mil is pretty thin, maybe good for one trip

2 mil is better

3 mil – 2 ounces /square yard

2 mil – 1.3 oz/yd2

1 mil – 0.7 oz.yd2

I've been using the PF sheet from Suluk 46, in the 1/8" thickness. It provides a bit of insulation along with some puncture resistance. Weight varies depending on what size you cut out. About 2.5-3.5 ounces.

This isn't quite UL unless you are comparing the weight to traditional ground sheet materials. But it is about the same as my old Tyvek ground sheet.

I agree with Eugene, a painter drop cloth is much easier to use than polycro and MUCH tougher. The 1 mil thickness drop cloth is light enough and folds small enough.

I just put narrow duct tape corner tie-out lops on it for my TT Moment and it stays in place with the corner elastics holding it. STAYING IN PLACE in high winds is critical and polycro is just too easy to blow away – or shred – when you're not in your tent.

Tried polycro (heat shrink-wrap from LOEW'S) and got only one use from it before it self-destructed. Too easy to tear, too difficult to unfold and put in place.

It's definitely possible to go without a groundcloth. If you are a bivy camper, you can use the waterproof bottom of your bivy sack as a groundcloth. What I usually do is sleep with my foam sleeping pad on the ground and my bivy sack on top of that. This works for me in every type of condition–wet, dry, etc.

"Does anyone here have any feedback on those expensive Zpacks ground sheets? Spefically puncture resistance."

Eugene,

I have a .7 oz zPacks cuben poncho/ground sheet. I have probably used it 20 nights so far, all in desert hiking. The key is site selection. I also use a 1/8" foam pad on top if it as part of my pad system, I think this will help to minimize potential holes since I almost always have small pebbles or worse in the places I frequent. So far it has been fantastic as a ground sheet and a poncho. Clipped to my Hexamid, it becomes a bathtub floor, which makes it easier to keep life organized. Highly recommend the entire set-up.

1 mil for me too.

1 $2 package will yield at least 4 solo sized sheets. I seem to be able to manage at least a week's worth of nights per sheet. I've used polycro also. I don't think the slightly better longevity of it really outweighs the cost and availability of 1 mil painter's plastic.