Can proper use of a groundcloth (or something else?) replace the "need" of a bathtub floor?
I feel I may be scaring myself into undervaluing the effectiveness of non-bathtub floors when it comes to heavy rain.

If you select your site properly, the chance of water running onto your groundcloth is pretty minimal. However, never say never....

I have a tent with a bathtub floor. Once, water leaked in for some reason, bathtub floor prevented the water from running off.

No need for bathtub floor.

When you use a tarp and groundsheet you never have a bathtub floor.

Also, good point about a bathtub floor trapping water on the inside.

I'm going to say "normally" they are unnecessary with two qualifiers.

First if it rains hard enough even a site that looks very good can be wet. Once in Colorado I camped near the top of an isolated knob. By "near" I mean the top was just a few inches higher and I would have been on top if there hadn't been a log in the way. It rained hard enough to create a river under my tarp starting from the top of that knob (maybe 10 feet away). When its raining that hard I'm not sure anyone can find a perfect spot every time.

Second in some areas you may not have the luxery of choosing a perfect site. Areas with designated camping sites might be an example.

Now if its sounds like I'm pushing bathtube floors I'm really not. I don't even own anything with a bathtube floor at the moment. However if you expect A. lots of hard rain and B. limited site selection, then a bathtube floor might be worth the extra weight.

In the rather squelchy UK - they are pretty much de rigeur for trips of any length...

Nice, but spendy and heavier. If you oversize your ground cloth and roll the edges **under**, you can approximate the same. Back in the day, it was recommended to make a tiny trench around your tent, but that is passé of course. I've suffered too many nights with a little cold river running somewhere under my shelter. With the compacted soil in well used campsites it can be hard to avoid.

A hammock cures the problem completely :) I'm good to 18" of groundwater!

I agree with most others that have said "not usually" in some way or another.

There are exceptions of course. Living where I do the ground is constantly not just wet but constantly muddy. A classic example of that can be this photograph. Trails here can go on like that for miles. Some might say that a hammock would be the ideal solution to resolve that matter - however, ever try putting a tree-strap around a Redwood tree that is 30 feet around ;) lol. I have... lol

At the moment my setup looks like this.

Setup exists of:

ZPacks Groundsheet Solo+Plus, Light
ZPacks 0.34 CF 6x9 Tarp
GossamerGear Thinlight Insulation Pad 1/8" Pad
Ruta Locura, 6 inch Carbon Fiber Stake (x6)
Ruta Locura, 9 inch Carbon Fiber Stake (x2)
ZPacks Cuben Fiber Medium Stuff Sack
ZPacks Cuben Fiber Stake Sack

A simple 6x9 tarp with the zpacks solo-plus groundsheet under it allows me a good three through five inches of bathtub height and enough width protection to keep my gear out of the mud. Total Shelter Weight of 306 grams (10.79 oz / 0.674 pounds)

When it does happen to dry out here in the Redwoods I ditch the groundsheet and go with a Gossamer Gear Polycryo Ground Cloth (Medium cut down in size) which saves me 54 grams and puts me at a Total Shelter Weight of 252 grams (8.889 oz / 0.674 pounds).

So anyway, I am with most everybody else here in saying yeah, really not something the average hiker needs in most situations. But, at times, they are a piece of gear you just should not leave home without.

John B. Abela
HikeLighter.Com


(edited to not have photograph display... was to wide for the website template)

Edited by JohnAbela on 04/17/2012 04:03:46 MDT.

The extra weight of a little wall is extremely small.
The extra security of a bathtub wall is great.

But, HYOH

Cheers

Perhaps in the modern, ultra-minimalist era, the extravagance of a bathtub floor is "too heavy", but coming from my experience with tents in storms before bathtub floors became a standard, I'll gladly carry that weight.

The old trench-around-the-tent comes from a pre-bathtub floor era, and good riddance, I say.

Recognizing that my tent is heavy by UL standards, the bathtub floor still protects from rain, snow, spatter and etc... The only water it could "hold in" would already have been there without the bathtub shield, and will certainly be way less.

Dry, summer weather? I'd sleep on a ground sheet w/o the tent, but would never want to be in a product that wasn't smart enough to work in snow and rain, in any place where either were possible.

To numerate Roger's point, a 5" bathtub wall for a typical 2-person floor at 50" x 86" adds exactly 1 square yard of fabric. That's about an ounce and half for silnylon--less or more for other fabrics. Pretty cheap insurance IMHO.

-H

My typical setup is a big tarp with flat polycryo ground sheet. I do have a thick Neoair that keeps me off the ground a bit. This setup served me well last month with 3 nights of rain in the Smokies.

"The old trench-around-the-tent comes from a pre-bathtub floor era, and good riddance, I say."

The trench-around-the-tent comes from a pre-environmentalist era. Most people, now, don't like to deface the natural environment.

Don't put your tent where a puddle or stream will form if it rains.

In the UK, and parts of the US, I'd say 'mostly'. It's not very often we get weather that is reliably rain-less, and even if it has been dry for days more often than not the ground is still soaking. However, there is the odd occasion when one can leave the tent and groundsheet at home with gleeful abandon. If only it were more often.

Jerry: "Don't put your tent where a puddle or stream will form if it rains."

Unfortunately, Scotland is where a puddle or stream will form if it rains. Unless you're on the top of In Pinn, which is sometimes the better option...

It's not just to keep water out.
The 5 inches of bathtub wall is about the same height of your head when sleeping.

depends on your environment, some tent rain fly lengths do not go to the ground. the bathtub wall protects your face from low lying cold freeze, or getting sand in your eyes in you are at the beach or the desert.

The downside on a hot summer night, is that the bathtub wall kills the face breeze.

My nephew in the boy scouts was camping at the beach in So Cal, middle of hot summer, almost tropical weather, freak rain storm that was not on the forecast, created rivers of mud from the cliffs down to the beach campground, similar to a flash flood. They were sleeping. The mud river was about 3 inches high, the bathtub wall is 5 inches of protection.

It's not the minimalist UL choice, I understand that a bathtub wall is overkill, but a well designed bathtub 3-season tent, can almost cross over into a temporary 4-season winter tent also.

It's a trade off of money, weight, versatility.

"Unfortunately, Scotland is where a puddle or stream will form if it rains. Unless you're on the top of In Pinn, which is sometimes the better option."

In the Pacific Northwest U.S. I can usually find a spot without puddle or stream, but occasionally I stupidly screw up.


"The 5 inches of bathtub wall is about the same height of your head when sleeping."

Sometimes, in really cold weather, breath will go from my mouth to bathtub wall and condense.

I have reduced the "bathtub" wall on my bivy to about 1 or 2 inches high. Actually, I'm more worried about keeping out sticks, dirt, and bugs. Short enough height to minimize condensation.

Necessary? Not at all. Nice to have? Sometimes. It all comes down to site selection. I have never had ground water under my shelter or ground sheet. Never. I hike in the Canadian Rockies and on Vancouver Island for frame of reference.

Ron Moak from Six Moon Designs has an interesting article on bathtub floors. You can read it here:

http://www.sixmoondesigns.com/blog/72-bathtub-floors.html

Great article, well written.
my take away from reading it is that:
1) UL bathtub tents are made of thin material that is useless to protect from under tent rivers. Whereas non-UL heavy tents can have a functional bathtub because the floor is made of heavy durable material.

2)invest time in site selection to reduce the need for bathtub floor.

All good and makes sense, but the article does not mention the use of an optional tent footprint to supplement the UL thin tent floor. Also for many areas, strategic rain diversion site selection is limited by many factors, such as terrain, trip timeline, and other-than-rain climate considerations:
example:
1) On top of a ridge, water will not pool up, but you may pick up another problem with wind.
2) on a slope water will not pool up, but you will slide in your sleep)

I don't think there is a hard and fast rule either way. It's all about trade-offs - weight, money, etc. Plus, where are you BPing and what is the weather/climate.

Personally, I approach my decision-making for gear choices based on functionality, not just weight.

While some may eschew the BT floor to reduce weight, however, you'll see some of the same folks also using a bivy and thicker camp pad. Both of which add more weight to the complete shelter system than is saved by foregoing the BT floor. But they may have other reasons than only saving weight, like ventilation, bragging rights, etc.

Having said that, I think there are times when either approach is appropriate. In hard driving rain, it may not be possible to find the perfect site for a tarp & flat groundsheet set up, much less spend much time looking for one. In this case, a BT floor may be the best option.

And, yes they can trap water if your overhead cover fails. I had my GG TheOne fill with water during a storm on the CT last year. Not a good thing to be bailing water while perched on a Z-Lite and trying to keep a down quilt dry, trust me!

So my recommendation is to critically assess your needs and make the right decision for your situation within your own constraints like cost. If you can afford it, the easy thing to do would be to have both and simply use what you need for the trip you're doing.

Good luck!