Condensation

[bluetongue]

A point that some manufacturers might consider when designing and making light weight shelters, I purchased in the UK following an overland odyssey in the late 70's a tapered A frame tent with a relatively roomy vestibule- one person - 2 with a very intimate squeeze. Can't recall the weight but it was certainly less than 3 kg. During the time I was in the UK it was used in a variety of 3-4 season conditions - however the thing that I remember most was that condensation was never an issue - either from the ground or above. A fairly solid tub floor catered for the former, but what I was most impressed with was the way the full cotton inner wicked away any condensation from above. The only real gripe was that it had to pitched inner first ( I have had a few ideas as to how i can reverse this and turn the pitching arrangement around) IMO the cotton added little to the tent mass and should perhaps be revived as part solution to condensation issues with some tent manufacturers in search of the holy grail of reducing weight.
I still have this tent = from Casey's in Bristol UK and is still my preferred weapon of choice when the going get rough. Mind you- itstill does not stop me from being a bit impressed with some of the gear from WE Macpac and Tarptent.etc

[Franco]

BlueTongue
You might get a better idea of why that cotton is not used any longer by doing a weight for size comparison with the newer stuff.
Your "1 person, two at a squeeze" description sounds somewhat similar to ,say, a Tarptent Scarp inner.
The Scarp inner is 385g , so if you weigh yours that may be a start.

Now if indeed the cotton absorbed condensation,that could be a problem. Useful when you sleep however in the morning your inner will be 500-1000g or more heavier than dry .
(from your perspiration as well as ground evaporation and possibly moist air)
Cotton takes a long time to dry much more than the nylon used for inners.
A good test would be to weigh the full tent dry, then set it up on grass, sleep in it and weigh it again in the morning before it drys , simulating the weight you would have if you were on a multi day walk .
Franco

[bluetongue]

Point taken Franco and how can I argue with such an authority on lightweight shelters. I guess my point was provided you were happy to contend with some of those issues you raised, it was my experience that the cotton inner overcame pools of water in the bottom of the tent in the morning. For those that can still remember- there were few options available in the 70's for comfort- it was either a li-lo which for the most part out of the question, but at least gave you some elevation from the flood, or a faithful old yellow karrimat, which put you smack in the middle of it.
FYI old faithful is 2240 gm c/w poles and pegs and sac; Inner only is 829 gm. ( both dry weights not taken early morning )
I might also add that the tub floor on old faithful is fairly bombproof & not requiring a footprint- a point that some manufacturers neglect to factor in when quoting weights. Perhaps an option may be to mix materials and have perhaps cotton where the most vulnerable parts of the inner attract condensation.
I am not a diehard walker locked in a time warp and certainly welcome some of the advances in weight reduction- particularly if it gives us old farts a few more years with the knees- but at the same time let's not throw the baby out with the bathwater. I am happy to carry a few more grams for a good nights sleep provided I can save a few grams elsewhere.
Ciao
bluetongue

[Ent]

Hi

User preference, ventilation along with air flow plus conditions largely govern condensation and even something as simple as a ground sheet that covers the vestibule can help. Some manufacturers get it right and some get it wrong and even within manufacturers' ranges are stars and dogs. For better or worst I look for tents with a sheltered vent at its highest point and a design that encourage air flow without freezing you to death. The Nallo and WE Arrow series share a similar concept of low to high vents and appear to get favourable comments regarding condensation.

The Akto is an interesting design study. Hilleberg redesigned the ventilation system and uses air permeable ends so you can stop spin drift and still get some ventilation. The first versions were rather known as being prone to condensation while newer ones are very good for a smallish one person tent but still get it.

Tent weight is a mystery to me. One person I know brought a few of the same tents and the weight difference was significant so while easy to criticise a manufacturer for stating the wrong weight it appears even exalted brands like MSR have significant tent to tent variations in mass. Good companies quote groundsheet weights separately. A brand like Hilleberg is less likely to need a ground sheet for protection while another brand this is almost mandatory. I use a ground sheet on every Hilleberg I have as it covers the vestibule thus making a clean storage area and have no great issue with condensation. Also I appreciate that the ground sheet can be attached to the tent thus adding nothing to the setup and removal times. Also handy in a blowing gale.

I suppose the best way of heading off condensation is having a tent big enough that the outer and inner are not pushed into contact. No small feat for people that do not conform to average population dimensions. It is one of the weird but true facts is that you can buy different size clothes, sleeping bags, mats, etc but not one manufacturer makes a design in say a long ans a short fitting Of the hundreds of models that crowd the marketplace not one. Makes you think lack of imagination exists in the tent design world. Sleeping bags for many years appear to be afflicted with that curse but now you can go from five to seven foot ones without too much trouble.

Cheers

[Stuntman]

..... It is one of the weird but true facts is that you can buy different size clothes, sleeping bags, mats, etc but not one manufacturer makes a design in say a long ans a short fitting Of the hundreds of models that crowd the marketplace not one.....

With the exception of the REI quarter and half domes. Three seasons jobbies that come in standard and "plus" sizes.

[Franco]

There are/were others, for example the Bibler i/Eldorado and the Pinon/Juniper, some Terra Nova models (XL or Space variant) and even cottage manufacturers like LHG with the Solo/So Long.
However not all designs can be elongated or enlarged. Fabric width and pole section length (section and total ) do put some design restrictions.
For instance , the poles in the Juniper were really too long and tended to form a permanent bend.
In the case of the Akto, I would venture to say that a longer version will sag even more under snow, so it would need extra end support or a different design altogether.
Anyway , this has nothing to do with condensation...
Franco

[Ent]

Hi Franco

I has been my experience that a sleeping bag touching a side wall acting as a wick to condenstation is a bad thing compared to a sleeping bag with pleanty of space around it. So size does matter regarding condensation, at least in my experience. Plus I have noticed that small tents seem to be more prone to condensation compared to bigger ones but that could be design issues. Also, as interesting it is to see consdensation build up under a fly is, an effective DWR inner means no great ill effect compared to a design or material that causes the condensation to drip on an occupant.

And thanks for the names of the different size tents. I will check them out. There is a significant percentage of the population that one size fit alls is not ideal.

Cheers

[Franco]

Ent
In that sense , yes size does matter..
(my comment had more to do with the condensation absorbing inner the OP described than condensation in general)

You already had listed a major culprit and that is a large vestibule.
One of the reasons for example that folk get less condensation inside the Unna than they do in the Akto.
(to comment on tents you like...)
Cover the vestibule part of the Akto and the difference will be a lot less . (ground evaporation)
(true to the many versions of this design (going back to one of the earliest (pre dating the Akto) , the Spacepacker by Robert Saunders, except that most ,like the original Akto, don't have any vents...)

Another is mouth to wall distance. This is again particularly noticeable in solo hoop shelters (low ends) , for example the Moment (to quote a tent I like...)
At 5'8" not a problem for me (and apparently not for a certain 6'3' guy , I wonder where he hikes) but it can be for guys over 6' .
A DWR fabric inner (the one in the Scarp...) does work to keep those condensation drips outside but if the internal volume is small enough it can also promote internal condensation possibly causing your down bag to collapse (after a few days like that) and or making you feel colder in winter and hotter in summer.
The zippable "window" (exposing a mesh area) in the Hillebergs is a good idea but many don't want the extra weight and volume.
As usual one needs to pick his poison.
BTW, the TT StratoSpire 1 is the large version of the Notch,the Moment is a smaller version of the Rainbow, the SS2 has more usable space than most "duo mids" and the Scarp 1 is a larger version of one of the tents mentioned above .
So there are bigger tents but not necessarily made in the shape/version you like.
For the record , I never have condensation puddles on the floor of my tents, however a mate of mine that sweats a lot does get a wet area under his Exped 7 ,on snow, on the floor of his Moment.
Franco

[Ent]

Hi Franco

Yes I agree that the low ends is an issue especially if you like thick mats such as Exped and Neoair and more so if you have a full head of hair as the wicking in extreme cold means a very wet head. This is the main reason why I brought the Nallo to use rather than the Akto was the height above the head. But the single hope over design as the Akto uses appears to be the current winner in weight to size calculations. The Nallo or similar designs are much more pleasent places to be for me. My love of a covered vestible area looks to be a major issue why I am rarely troubled by condensation except for days where my clothes and pack are soaked. With the double ended Kaitum it is then end that very wet packs are stored in that gets the most condensation.

Cheers