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Craig W.
(xnomanx) - F - M
XUL Definitions on 07/15/2011 16:56:01 MDT Print View

As all of this has been jumbled into one long thread, I thought separating this would be good.

From Bradley Attaway:
"First, thoughts on an XUL definition:

While it's tempting to follow the current trend of using the previous base pack weight tier divided by two--i.e., Lightweight is considered to be sub 20 BPW, UL is generally considered to be sub 10 BPW, SUL is considered to be sub 5 BPW, which would logically make XUL a sub 2.5 BPW--once you're hitting this level (really, once you're even at SUL) the clothing you wear and poles you (might, or in my opinion ought to) carry are too substantial a portion of your load to give any measure that doesn't include them salience. It is therefore necessary for XUL to be FSO based.

At these weights, many Sub 5 FSOers won't be "backpackers", as the activity is understood from a traditional perspective (or lightweight, ultralight, or superultralight) but adventure racers or ultramarathoners and the like. Unfortunately, for these (awesome and crazy) pursuits a 5lb FSO may be considered heavy!

XUL then, need specifically refer to the weight for a backpacking loadout, including "the big 3" of sleep, shelter, and cook systems. I feel without these, the pursuit is no longer properly "backpacking", in which case the weights to which XUL is supposedly relative no longer exist, and the definition thus void.

Moreover, the loadout should be effective for 3 season trips of several days on Class 1 and some 2 terrain in a variety of weather conditions; that is, temperatures down to freezing with the possibility of sustained moderate precipitation and considerable winds with several miles between water availability.

As a big guy, I wish I could create a rigorous definition that allowed a higher weight based on height or mass or foot size (even light size 15EEEE shoes weigh perhaps half a lb more than average sized shoes of the same model, so there goes 10% of my total loadout right there!), but I can't think of one that wouldn't be arbitrary, and since 5lb FSO is arbitrary already (like LW UL and SUL are as well) I think it's better to be simple and arbitrary than complicated and arbitrary.

Definitions set, we come to the point:

XUL thus rigorously, if arbitrarily, defined as 5lb FSO, the best goal, in my opinion, of an XUL gearlist (or any gear list for a category where weight is the given) is not to get simply lighter than the defined weight, because the weight is given, but to hit that weight more elegantly: more comfortable, practical, cheaper, etc.

Alan Dixon (Dixon=Adventure?) perfectly demonstrates this idea of elegance in load with his "full comfort UL gear list" ( He's not trying to be lighter than the arbitrary UL definition, he's trying to do UL as elegantly as possible. Likewise, he included a cook system in his XUL Appalachian gearlist(, because he felt it more elegant.

People will say the above definition is arbitrary and ask what purpose it serves in practice. I agree it's arbitrary, as the definitions of LW and UL and SUL are arbitrary, and the purpose this lower weight tier serves is exactly the same as those above it: longer miles, more comfortable hiking, etc. People will then ask, "does XUL make a practical difference over SUL or even UL towards the achievement of these goals?". In fairness, I don't know, I believe it will make SOME difference, but I don't know. What I do know, is that it sounds like a fun exercise to me, and I think it's an exercise that will inspire and push our little pursuit and its supporting industry forwards.

Earlier in this thread, Craig and I agreed to assemble and test XUL loads in the near future. To Craig, I invite your support of the definition I've laid out above by chasing the greatest elegance possible in our XUL loads, rather than making it a challenge of simply going lighter (I think at 5lb FSO that challenge is highly present!). I think this will make for some fun and standardized pseudo-competition, and since "elegance" is so subjective, it will make for some great debate about the various and necessarily creative solutions to the XUL challenge.

Credit where credit is due: Much of the above definition is inspired by Adventure Alan's article at In fact, his loadout will be my starting point in putting together my own XUL list for this challenge. I hope I've contributed something to the logic behind the definition he practiced. was my greatest inspiration when I decided to dabble in UL, and continues to be where I direct all newcomers to the pursuit.

Finally, on a personal note: I've just moved to the SF Bay Area and know no backpackers here of any sort. I'd love to meet and hike with anybody in the area! Having spent my whole life reflecting on and emulating that which I admire, I am as awesome as my talents have allowed me to embody the word as I have defined it. In arrogant summary: I am awesome*, let's meet up."

Craig W.
(xnomanx) - F - M
Re: XUL Definitions on 07/15/2011 17:14:21 MDT Print View

Full Skin Out, not including food and water, of around 5 lbs. seems to be reasonable to me. I'm more concerned with a minimal kit than numbers...but I do want a target to help force me to simplify even more.

Yes, it's completely arbitrary. To say that one kit is "simpler" than another just because the shoes are lighter, yet serve the same function, this is stupid. But for whatever reason, the sub5 FSO appeals to me as a target. So I'm gonna knock myself out. It certainly does appeal to me as a distance runner though. Less weight makes life easier.

I personally will count the weight of fuel if I choose to carry any. Within the whole XUL (or even SUL) mindset certainly comes the question of the necessity of a stove or cooking...I could argue that fuel is unnecessary. If I choose to cook at all, I plan on woodfire cooking or Esbit (using rocks as a cookstand). Most of my motivation to cook comes from the desire to still be practicing something that "feels" like backpacking; some hot meals, some comfort food, something to enjoy in camp. No-cook, XUL, long distance trips certainly start to blur the definitions between adventure racing or running and "backpacking".

Generally, I'm not going to get too hung up on numbers and definitions though. I think it's just a fun exercise in minimalism. Nor do I plan on spending my way to SUL/XUL comfort. I want to go entirely with things I already own. I won't be trading my 10 oz. ponch for a 4 oz. cuben one...unless someone wants to sponsor me.

As for us Southern Californians cheating, absolutely. I'm going out in the next couple days into the Angeles National Forest. I could easily find a way to sleep comfortably in running shorts and a t-shirt. The additional 5lbs certainly feel frivolous in weather like this. But hey, it's a start, and I'm having fun packing my bag.

Lightweight backpacking got me thinking about what I need.
Ultralight backpacking got me to question what I really need.
Now it's fun to figure out what I really really need...while maintaining a reasonable standard of comfort/safety.

Reasonable standard...whatever that is.

I'm not quite looking at this from the how low can go perspective, unless you factor in a basic degree of comfort.

Subjective indeed.

Edited by xnomanx on 07/15/2011 17:20:04 MDT.

Bradley Attaway
(AttaboyBrad) - F

Locale: San Francisco Bay Area
Glad this didn't didn't spark, I changed my mind on 07/15/2011 19:49:00 MDT Print View

I'm honored to be quoted in the first post of this new forum. Not so much because it's today's cause celebre, but because its creator Addie is most surely a babe so schmokin' she must plan trips around high fire risk areas.

I was worried I'd come back and find out that SUL/XUL definitions were the third point on the backcountry guns/electronics ninja star of "You don't want to go there".

As I was napping through the latest Harry Potter movie (sad to say, without an attachment to the characters, which I even have, the movie can't well stand on its own) I changed my mind about the whole FSO vs. BPW thing.

I liked FSO because it limited the potential for "cheating" by counting items as worn. I didn't like the definition I proposed because too much variance in the solutions to meeting that arbitrary weight are dictated by the size of the solver--as I pointed out: my shoes are much heavier, my clothes require more cloth, my trekking poles are 30% longer than a small fellow's, etc.

I woke up to the sound of Voldemorte's snake Nagini chomping the bejeezus out of Severus Snape and realized that the vast majority of FSO weight variance between me and somebody a foot shorter is counted in clothing and equipment worn. We probably both have frameless packs, which often don't have sizes the way framed ones do, my sleeping pad may be 6 inches longer, but that's probably less than an oz. of XUL sleeping pad, and my Jacks R Better long quilt is only 2oz more than one of normal length. Everything else that goes in a pack ought to be equivalent.

For these reasons, I'm going back to using the previous tier BPW divided by two as my own definition of XUL, that is 2.5lbs BPW. This keeps with my homage to Adventure Alan's 2.4lb BPW loadout and solves to large extent the problem of comparing the XUL strategies of people of different sizes.

But what, then, of cheating? Well, I guess people are welcome to stuff their sleeping pads in their trousers and call them "worn", but at these low weights I don't think anybody will be bringing much extra in the way of wearable things. Rather those extra things that might questionably be counted as "worn" will instead be left home by making packed things multi use--i.e. rather than bring a raincoat I'll use my poncho tarp, and rather than bring an insulating layer I'll use my wearable quilt, etc.

Anyway, fortunately nobody seems to much care about rigorous XUL definitions, but for anybody wanting to join me on the exercise in the future, I'll be going for the maximum backpacking comfort I can get at the lowest cost at a 2.5lbs BPW, meeting the trail conditions laid out in my original post quoted at top.

Jason G
(JasonG) - F

Locale: iceberg lake
Xul on 07/15/2011 20:06:49 MDT Print View

Brad, sounds like you need to come up with a body height/weight to pack weight equation to further define. I'm a bigger guy too(6'3-210), and my gear weighs more standard but I feel my added mass/strength makes up for it. (I'm not sul/xul btw.8-10lb bpw fwiw)

Bradley Attaway
(AttaboyBrad) - F

Locale: San Francisco Bay Area
Re: Xul on 07/15/2011 20:37:39 MDT Print View

I addressed this somewhat in my original post.

I'm sure equations could be made, but they would be arbitrary and unnecessarily complicate the definition. Any weight definition is already arbitrary (though at least XUL=SUL/2 is based on an accepted pattern of arbitrariness). I believe simple and arbitrary is better than complicated and arbitrary.

2.5lb BPW as a definition of XUL should get rid of most of the variance caused by people being different sizes, and still include the vast majority of gear, as explained in my second post. Worn items can then be evaluated separately, while allowing an inclusive and comparable-between-persons category of XUL.

I think going over 7lbs FSO is probably not a serious attempt at XUL, but my old New Balance 991 sneakers in 15EEEE weighed more than a pound and a quarter each, and I wouldn't want to exclude Bigfoot from tackling XUL simply because they like a comfortable trail runner. For that matter, I wouldn't want to exclude people tackling such technical terrain that even boots are required, and my Lowa Ranger GTXs (at size 15, my options are EXTREMELY limited for mountaineering boots) weigh nearly 5 lbs for the pair. Why should somebody tackling terrain requiring boots compatible with full crampons be excluded from the XUL discussion?

I feel ya on the "I'm a big guy, who cares if my stuff weighs more" logic, but at the same time, that's the sort of thinking that used to put 70lbs on my back ;-) I'm going after this XUL challenge Craig has laid out and I have defined with excessive rigor. If I can hit these weights, I think it's possible for somebody of nearly any size.

Edited by AttaboyBrad on 07/15/2011 20:43:32 MDT.

Jace Mullen
(climberslacker) - F

Locale: Your guess is as good as mine.
Re: More Confusing Arbitraryness on 07/15/2011 21:21:19 MDT Print View

I think another way of dealing with this, in another arbitrary way is to, after SUL have a new catagory by the pound. Thus:

Under five pounds would be SUL
Under four pounds would be ÜL (uberlight)
Under three would be XUL
Under two could be XÜL
Under one could be SXÜL

Joking aside, I do like the idea of having an Uber light (I like the sound of it, and plus, I feel cool saying it). I move for packs weighin between 2.5lbs and 5lbs be known as Überlight. I also agree with the idea of XUL being a 2.5 lb baseweight for three seasons with weather. It is all to easy for us SoCalers to cary practically nothing and still be comfy in the summer.

tommy d
(vinovampire) - F
location location location on 07/15/2011 21:26:05 MDT Print View

Based on the first day of activity on this forum, XUL backpacking may have to be defined as a type of backpacking that occurs during the summer months in the San Francisco Bay Area of California.


In all seriousness, in my mind, the major points of that must be made are the following:

SUL Backpacking should be defined as hiking and camping, while carrying your own gear, which has a total base weight of no more than 5.0 lbs. In addition, no porters, pack animals, or motorized assistance should be used. Trips should be self-supported, without (a) aid stations supplied with wet sponges and little cups of water (sorry runners), (b) stationary, man-made shelters such as cabins or huts, and/or (c) caches of gear (with the exception of consumable items cached for resupply).

Base weight MUST include, but not be limited to the following: map, compass, signaling device, and first aid kit. And honestly, if you take pictures on your trip, you should really include the weight of the camera or camera phone.

In areas where a bear canister is required by law, the weight of the canister will not be counted towards the 5.0 lbs limit, but instead an asterisk * should be used next to the weight and a sincere written apology for being responsible and law abiding.

In areas where there are Class 1 or greater Hurricane strength winds, a 4oz wind shirt will be allowed to be added to the 5.0 lb base weight upon approval by a SUL Guru and with an asterisk as described above.

Finally, there will be NO base weight standard set in (a) areas outside of the Bay area and (b) during the winter months. During these months, all SUL backpackers must be at home working on spreadsheets and overseeing their mom's sewing them new tarps.


Jason G
(JasonG) - F

Locale: iceberg lake
Jul on 07/15/2011 21:41:11 MDT Print View

"Under five pounds would be SUL
Under four pounds would be ÜL (uberlight)
Under three would be XUL
Under two could be XÜL
Under one could be SXÜL "

Why stop there?? If I'm feeling frisky, ill take out my sul; XÜL;ul kit. Aka THE FORCE! weighing in at a whopping 4.3398 nanograms i can go can out for 16.3 days with each piece of lambic bread. Trust me though..this isn't for the faint jedi.. Took yeeeaarss of training

Bradley Attaway
(AttaboyBrad) - F

Locale: San Francisco Bay Area
I tried SXUL on 07/15/2011 22:02:19 MDT Print View

As a joke I actually tried to put together an SXUL list (1.25lb BPW) meeting the conditions criteria laid out, and failed miserable as soon as I added any sort of quilt. Even my 900fp down JRB Stealth is a full pound and only good down to 40 degrees. Can hardly find a 30+ liter pack for under 4 oz, so that plan went bust right quick.

Within the conditions laid out above, I think XUL (2.5lb BPW) is nearly the lightest one can conceivably go, regardless of expense.

Jason G
(JasonG) - F

Locale: iceberg lake
Hmm on 07/15/2011 22:30:15 MDT Print View

So brad.. I checked your profile and saw you went on your 1st "UL" trip a few weeks back.. (with a 4lb quaterdome no less)??? Don't your think you should acquire some real ul or sul gear and actually go on a sul trip before you go defining terms (as lame as that is by itself) that you have no experience with?

Christopher Davis
(CDavisJK) - F
no pack on 07/15/2011 22:32:15 MDT Print View

You don't need a pack at this weight. Just roll your quilt into a bedroll with your stuff inside it and tie the ends off, then tie them together and sling it over your shoulder.

Craig Price
(skeets) - MLife

Locale: Melbourne, Australia
XUL forum? on 07/16/2011 02:39:08 MDT Print View

After reading the companion thread on this forum, I'm now waiting to see someone try to convince the adminstrators to create an XUL forum as well.....just joking! ;)

Bradley Attaway
(AttaboyBrad) - F

Locale: San Francisco Bay Area
Re: Hmm on 07/16/2011 02:39:59 MDT Print View

Lack of experience in XUL I more than make up for with experience in defining terms. How else would we know what we're talking about? XUL has no agreed upon definition. For that matter, how could anybody have experience in something that hasn't been defined?

With that tent, my BPW was 12 ish lbs, it was my only two man tent at the time. Rocking a Hexamid later this week.

I put in over a hundred miles in the two weeks following that with 8 lbs, applying the research I did following that experience.

Since then I've covered some hundred plus miles with a BPW of 6 lbs. The perks of the NorCal freelancer with too much time.

I have, at several points, admitted I am new at this. If you've looked over my profile, you've seen how I've invested in this community in the short time since I arrived.

If you've read this thread then you've also seen I intend to do some XUL trips. With whose gear do you expect I'll do that? Does cuben fiber swaddling show wisdom in this area by itself?

An "XUL" challenge was issued, the inspiration of this thread you've hijacked to call me a noob, and I figured if people were going to participate in that challenge, perhaps a shared definition to work off of would be helpful since I've seen none established. I have a propensity to get overly thinky when I have too much time.

Read my posts, evaluate the quality of my arguments, advice, or even prose, then either engage in constructive debate or point out where I've gone wrong. You can keep the glib superiority and name calling. I'm enthusiastic and educating myself about this pursuit, warmed by the inclusiveness these forums have shown me and other newcomers, and will continue to contribute my sometimes academic knowledge where applicable until the miles passed have turned the academic wholly practical.

If I've mistaken your tone or missed intended sarcasm, I apologize.

Edited by AttaboyBrad on 07/16/2011 11:17:09 MDT.

Sean Staplin
(mtnrat) - MLife

Locale: Southern Cdn Rockies
Good reply on 07/16/2011 08:48:35 MDT Print View

Good reply Brad. My experience going lighter over the years may be different from others. I was always a minimalist, even when each item of my gear was heavy. I started using just a bivy 30 years ago. I still have it and it weighs 23 oz. Pack an old Millet reinhold messner at 57 oz, bag a MEC swan mummy at 48 oz, stove the original MSR blast furnace, when I took a stove, lol. The thing is my techniques have not changed much in 30 years, (just the distances covered), and my base is 6 lbs for longer trips and less than 5 for long weekends and I haven't weighed what I take for quick overnighters,( I can get to the place in my avatar in 3 hours walking from my house).
I have also been on these forums for a short time and have picked up many great tips. The gist is I now use the same amount of equipment, just lighter, and in many cases superior to what I used in the past. Being a noob is not a drawback. Backpacking is a pretty easy thing to do and becoming competent can be achieved in a short period of time.
I like reading your definitions and in reality it doesn't matter much what we call it, but it is fun. Maybe in the vein of Carolus Linnaeus we could really have at er.

Edited by mtnrat on 07/16/2011 08:53:14 MDT.

Aaron Sorensen
(awsorensen) - MLife

Locale: South of Forester Pass
Re: XUL Definitions on 07/16/2011 20:56:48 MDT Print View

Good deffinitions

I do believe that we need some type of conformity with the term SUL and beyond.
If you look at other backpacking web sites, (which I hardly ever do) there are other terms used for going beyond UL.
So before there is conformity there first needs to be a unity.

On the other hand, I rarely post, or like to post a base weight or even a FSO weight. There are only two weights I use.

The first is to put everything in my pack that I will not be wearing at all times, or at least at the start considering changes of clothes. I also add or put all my food in my pack and weigh it.

I consider this my "Base Weight"

Since I will be carrying all my food in the beginning I consider it a base.

I then figure out the average water I will be carrying and half of the food weight and call this my "Average Carried Weight"

It's not that I even like these terms for backpacking, it just works best for me.

Glen Van Peski
(gvanpeski) - F - M

Locale: San Diego
Re: XUL Definitions on 07/19/2011 21:24:42 MDT Print View

Good luck on getting 'correction factors' agreed on for those of us with above-average mass or height! I've had spirited discussions with Ryan Jordan about just such matters on trips. I think I finally pestered him into spotting me a half ounce once...

Jace Mullen
(climberslacker) - F

Locale: Your guess is as good as mine.
XUL Definitions on 07/20/2011 00:13:02 MDT Print View

Glen, I would argue that even though you are a giant, you are like a toothpick. So it makes up for it. I'll give you 3/4 oz



P.S. I have officially decided that Überlight is less then 2.5lbs BASEWEIGHT

XUL can remain 5lbs FSO

John Abela
(JohnAbela) - MLife

Re: XUL Definitions on 10/30/2011 23:47:54 MDT Print View

Hello All,

Felt I would jump in on this issue. As so many others have said a base standard classification is just so hard to do these days. So many different variables to take into account.

I will fully admit that my own classifications are not “standard classifications” – and that is because it seems nobody out there has been able to really standardize hiking classifications. There are those who claim they have, and you have sites like wikipedia that people keep changing back and forth, but the fact is pretty simple: thus far there has been no true world-wide standardization of hiking weight classifications. I really do not care to argue about these numbers, as I pretty much think none of us do, so the below is just what they are, ‘how I define them’.

I define them the way I do based upon how much skill a person should have, and how much a person has probably learned in order to reach each of the four levels. Yes, a person can go out and buy their way into a SUL or XUL setup, but time will quickly show to other hikers that they bought their way into said weight level and have not done it the right way – by learning and gaining experience as you go lighter and lighter.

All weights below are “base pack weights” (BPW) – which I consider your backpack weight before perishables and consumables.

HH – Heavy Haulers = Anybody with a BPW of over 15 pounds

UL – Ultra Light = Anybody with a BPW of between 8 and 15 pounds

SUL – Super Ultra Light = Anybody with a BPW of between 3 and 8 pounds.

XUL – eXtreme Ultra Light = Anybody with a BPW of under 3 pounds.

To me, classifications are more about experience and wisdom gained from being on the trail and spending a lot of nights outside; not about how big your pocket book might be and what you can buy your way into.

For the record, as of the time I am writing this, I have three different setups. A winter setup that is in the 5 pound range, a shoulder season setup that is in the 3 pound range, and a summer time setup that is sub two pounds. You can see my gear if you would like, but again, I feel that standard classifications should focus more on the knowledge that we learn along the way than about the final gram count. If I can learn one key aspect of hiking for every 100 grams I remove from my pack, I feel good about myself!

Nick Gatel
(ngatel) - MLife

Locale: Southern California
Re: Re: XUL Definitions on 10/31/2011 00:02:17 MDT Print View

I think any kit should be able to handle a trip longer than a weekend, at least a week. This way the only variable is the weight of food. The kit should be able to handle rain, wind, maybe a light snow, and temps down to at least 32F. It should also include a stove. It requires shelter, rain gear, wind gear, and puffy insulation. This kit should handle most 3 season trips. Plus summer in the mountains can mean sub-freezing temperatures.

I don't think anyone can put together a base weight of 2.5lbs or less and be safe and comfortable for the above mentioned criteria. I do think a FSO of 5 lbs is doable, but not easy. The one thing I don't like about Alan Dixon's kit is his use of a quilt as his insulation layer. I don't want to risk my sleep system as insulation too.

John S.
(jshann) - F
Re: Re: XUL Definitions on 10/31/2011 05:48:16 MDT Print View

UL - Packed base weight under 10 lbs (originally 12 lbs, IIRC)

SUL - Packed base weight under 5 lbs

XUL- Packed base weight under 4 lbs (original); others define as total base weight (packed plus worn) under 4 lbs