About the H13

[Julie Danger]

Yes, tricky design.  I talked with my nearest engineer and he's unsure of its stability, he recommends the 10' hexayurt over it which surprised me.  If you make one, get really smart about the way that you lash it down-- maybe two rope halos, for each peak?

I do recommend 4 separate roof sections because they minimize and stabilize shipping space. Another flat piece of tape on-playa isn't that difficult.
There are two ways to bisect the roof, but one side looks like a standard hexayurt, the other looks like...something else, and has the "high flat face" where a door would logically go. If we're talking about the 'traditional looking' half, yes: you can join 3 triangular panels with 3 tight hinges--but be mindful which ones you pick! I prefer the 0.5x loose hinges on that side, partially because I'm used to it, and partially because tight hinges joining the "kite" will create funnels for water in the instance of rain. Perhaps not disastrous, but the loose hinge is ironically more stable.
For the "different" half of the roof, with the door face on it: DO a tight hinge from the inside on those kites.  My initial instructions were plain wrong: the math worked but it was very unstable.  This will also create a funnel for rain-- you can always add some 3" tape from the outside after the hexayurt is constructed

One of the recent builders said it seemed unstable when assemble just using tape patches: the tape ring that joins the roof to the walls is a critical element of stability, as is the way you guy down the yurt (again, a rope halo might be best on an H13, perhaps in combination w/ tape anchors). So, stability should improve. However, I realize: a nice tall door will cut into the tape tension ring! This, plus the instability that asymmetrical structures have, makes me advise you to overbuild it!

Any H13 builders, please consider shooting some video, even if it's crappy video!  You don't even have to talk-- in fact, no language is preferred for the international community.  I'll happily edit it into something useful.

Thanks!
J

[Vinay Gupta (Hexayurt Shelter Project)]

Very interesting, Julie. I'm definitely of the opinion that the H13
*geometry* is absolutely amazing - the one we built out here feels
great - but it handles forces quite differently from the standard
hexayurt and that's going to affect the way it's constructed. Lot of
big, flat surfaces - the 8' vertical area at the front, and the
parallelogram roof

It's going to be interesting to see how they hold up the first year
they are on the playa, and it's an important time in terms of learning
what works and what doesn't Scott and Dylan's new design. If anybody
just nails it ("this is exactly how you do it in polyiso for the
playa, it's dead easy and rock solid!") it's really important we
capture that.

With the regular H12, I'd four or five years of doing them at Burning
Man before it went big. I'd made a fair number of mistakes, none of
which resulted in a failed hexayurt, but all of which were learned
from before we documented what's become the H12-Classic-Polyiso
design. I've seen one H13 built of polyiso by Herman's crew for the
Changing Tents event in Brussels but, frankly, there wasn't much wind,
it was anchored (classic tape anchors) to seven half-ton concrete
blocks, and they had it built before I got much of a chance to suss
out how it worked!

So, yeah, overbuild and caution. It's the H13's first year on the
playa, and those building them need to be aware that we don't know how
they'll compare in practice. I will say that, as far as I know, there
hasn't been an H12 failure at Burning Man, which probably means that
the H12 is substantially *over*-specified, or we'd have seen
occasional failures when dodgy construction met an unusual wind, so
there's probably a bit of "engineering margin". But it's a nice
feeling to be doing what you know works and has worked before,
although it's a lot cooler and more exciting to be expanding the state
of the art!

Good luck, H13 Burning Man Test Crew :-)

Vinay

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[dou]

Another way to bisect the roof is as shown in the picture of the model attached, and to use all tight hinges (some from the inside, some from the outside). It does pack just as well as the four-piece roof + two-piece walls, and I'm still thinking that it will improve stability to have a roof with all-tight-hinges. Some minimal taping (or pieces of plastic) at the end of the inside hinges should be able to direct water outside from the funnels of water.

We were hoping to get this built and documented by now, but due to a number of setbacks, we only managed to build half of it. We'll have to finish when I come back to the states just before burning man, so unfortunately I won't be able to comment further until then.

Good luck,

-dou

[Lorin Basche]

I'm currently constructing my H13, and I've got a few questions. First
of all, regarding the walls, is there a reason that the base can't be
assembled as one piece instead of 2? I'm trying to limit the amount of
taping that will be required on the playa, and figured it would be
easier to simply add another tight hinge to connect the panels
together. I know that having them separate allows you to sandwich the
roof pieces in between them for transport, but that's not that
important for me with how we're packing. Also, regarding dou's semi-
folding roof design, what are your thoughts Vinay? I know structural
integrity comes from how everything is taped together, and I don't
know if having the roof triangles with tight hinges folding inwards
instead of outwards on the flat surfaces would cause any loss of
strength, and if it did, if that could be easily solved by simply
taping the inside of the seem as well during setup. And then my last
question, which seems to get very little attention (or maybe I just
failed to look hard enough x]) is what is the best way in which to
build a door for an h13? I'm at a cross between wanting to use the 8
foot side of the yurt for a full sized door, or for just more headroom
while inside. If I put the door on one of the 4 foot sides, I know I
would gain more structural integrity since I would be able to stretch
a single piece of tape all the way around the yurt where the roof
meets the walls, and would actually have more usable headroom inside
since the side with the headroom could actually have things positioned
next to it instead of having to leave it clear for the doorway. But
either way, I don't know the best way to build the door. Do I cut out
the full door then tape it back on with a tight hinge? Do I need a
sill at the bottom and if so, what should I make it out of? What do
you use as a clasp to keep the door shut? and is an inward or outward
swinging door better? I'm installing a swamp cooler as well, so I'll
have outward pressure. Any advice would be much appreciated! Thanks!

[andreas]

I just constructed a full-scale H13 using dou's rearranged hinge
method today to bring to the playa this year.

It works great!
The two-piece design made it nice and easy to put together the roof on
the ground with 3 people (since we may have to), then grabbed 2 more
to lift it onto the walls.

Great mod, dou!

>  Four_H13_pieces.jpg
> 80KViewDownload

[andreas]

Lorin:
I can't speak for the reason for two wall sections... but perhaps someone can?

We ended up doing our door on one of the 8 foot sides, hinged inwards, for the following reasons:
- Two of us are over 6 feet tall, and part of the reason for doing the H13 was so we wouldn't have to crawl to get in and out. The other was so we'd have more usable space.
- We cut out the full door and then hinged with a tight hinge. 
- We did NOT do a sill at the bottom, because though it would be far better for rigidity, we knew that it would get stepped on/kicked and broken in the first day of use.
- The door hinged inwards means that the wind can't grab it and snap it off, plus any positive pressure (also doing a swamp cooler) will tend to push the door closed rather than open.
- Still working on the clasp, but I'm thinking a piece of wood on each side, sandwiching the door, that then can flop over onto a rest sandwiching the wall as well to keep it closed. (if that makes sense). 

Getting very psyched. :)

[Steve Upstill]

Is there a definitive recipe for this? I'm just gearing up for a regular, default H12 (built one before), but if there's a recipe where I don't have to spend hours scratching my head I might switch.

Thanks,
Steve
--
They laughed at Copernicus. They laughed at the Wright brothers. Yes, well, they laughed at the Marx brothers, too. Being laughed at does not mean you are right.
-- Michael Shermer

[andreas]

Steve,

I'm not sure if there's any step-by-step done yet...
I used a combo of the info here:  http://www.appropedia.org/Hexayurt_H13 
and Dou's picture.

Since (as I understand it) the H13 is not yet playa tested, I'd guess there will be a lot of changes.
I figured I'd be a guinea pig.

[Lorin Basche]

Awesome! thank you Andreas! Yea this is my first year building a yurt,
and I'm also 6'3" so the h13 definitely interested me. I think I will
end up putting the door on the large side and just wrap the horizontal
piece of tape used to secure the roof to the walls around the walls of
the door frame and inside to ensure strength. I'm stoked someone built
the 2 piece folding roof design first to ensure it worked. We're also
going to help with the wind by parking our car with the uhaul trailer
attached about 5-8 feet in front of our door to break the wind, and
also provide an easy way to setup a sort of awning between the uhaul
and the yurt. Gah, so excited!!

[Lucas González]

Added to the appropedia page  http://www.appropedia.org/Hexayurt_H13 

2011 will be the first year the H13 is used at Burning Man, so we can't say it's been "playa tested". It's been suggested that you slightly overengineer for wind and circular strength, consider building foldable at home to test and refine, and maybe ask for help and comments at http://groups.google.com/group/hexayurt

Is that ok as a warning? Any more specifics or different wording?

Lucas

2011/7/18 andreas <andre...@gmail.com>

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[dou]

This is great! I'm very excited that someone built the two-roof-piece model. Thanks, Andreas, for giving it a try and letting us know. Also, Lorin, I never thought of combining the two wall pieces together since that part comes from the standard and well-tested H12. But you're completely right: Since the roof pieces can be sandwiched between the rectangular roof-panels anyway in an H13, you could combine all the walls together. I do agree with Julie, however, that this might lead to a very bulky block.

Steve, I have just prepared a google docs document with step-by-step instructions of how to build a semi-folding H13: https://docs.google.com/document/d/1CIqUJf76ZNPmZtZ4Xk_2t7aAkJypT9yKXsdzlNor0z4/edit?hl=en_US. As people have said (as well as disclaimers in the document), this is not a well-tested design yet. But it makes sense, we have at least one person who built it, and I will also be trying it this year.

-dou

[Vinay Gupta (Hexayurt Shelter Project)]

I'm not at all sure on the semi-folding roof design yet. I don't have quite enough of a feel for the H13 structurally - I've only built two, one using pretty much the traditional up-and-over strap tape anchor design, and the plywood one here. I'm generally somewhat uncomfortable with hexayurts which *don't* have the up-and-over strap and tape anchor design, although experience seems to be showing that a rope web is just as good on the Playa - at least they're not failing! I'm basically waiting-and-seeing on the H13 at Burning Man. Should be fine, but H13 increases the strain because of the large flat surfaces (front walls and the roof parallelograms) and the folding designs also strip one of the key structural features. The fact we've had practically zero (zero?) hexayurt failures at Burning Man probably shows that the Classic H12 is overdesigned, however.

The critical bit to remember is that the Classic H12 doesn't rely on the adhesive strength of the tape to hold it together. The adhesive strength of the tape keeps the tape on the surface, but *all* of the structural load is taken by the *tensile* strength of the tape. For the Classic H12 the hexayurt will stay firmly on the ground right up to the point where a piece of tape snaps. Some of the designs I'm seeing seem to rely on the adhesive strength of the tape, where the tape can tear off the surface resulting in a structural failure. The tensile strength of the tape is something like 400kg / 900lbs. The adhesive strength is much, much lower. So that's worth bearing in mind - are you relying on the tensile or the adhesive strength? On the other hand, a rope web is a pretty substantial tensile structure in-and-of-itself so it may be fine.

That's my thinking on this so far - I don't fully trust the folding designs yet because they're generally working on the adhesive rather than the tensile strength, and the rope web looks Pretty Good - so I'm basically cautiously optimistic about field performance, but

1> overbuild. Consider putting large (6' long) straps of tapes perpendicular to hinges so there's a long spread of force accross the panel, not just at the edge

2> at the first signs of problems on the Playa, hit it with actual up-and-over tape straps. It might mess up the hinges, but it'll *stay* in all probability

Also don't neglect the tension ring! It matters, hinges or not!

Document, document, document. The only way we're going to learn is by seeing lots of examples (flickr is your friend) and comparing results. This is all experimental science.

Good question,

Vinay

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[Steve Upstill]

...which reminds me: should we pass around probably locations so we can drop in on fellow Vinay fans? I don't have a fixed camp location, but I tend to gravitate near 8:00 and J, which is where a bunch of Iowans set up coffee camp. My camp has a big, spherical shade structure made out of curved electrical conduit and silver tarp (Anxd it's called, though we often do without signage. Will list the location at Center Camp.)

Cheers,

Steve

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[andreas]

Vinay's post brings up a question for me... I *had* been planning to do up-and-over tape anchors with the folding H13.  
How would you do it otherwise?  Just a rope halo?  Because I'm not sure how that would work on the H13 design.

I'd been planning to do an "x", basically,  with tape anchors and then do another "strap" over the peak of the gable.
Happy to hear other input though, as I just kinda made that up.  :)

Also, re: the instructions dou wrote up.... on assembly, rather than flip it over, we assembled it with the outside out.  Just tape-patched the short side of the two full panels to each other, then pushed them inward to make an a frame, then had one person crawl inside and do a few other strategic tape patches and that made the whole thing solid for us to lift onto the base.
I figured when we do it "for real"... before lifting onto the base we'd run the 6" over to do a full seam down the middle, and also do an X to make the tape anchors.

Thoughts?

[Lucas González]

Documaniac mode = "on"

Dou, can I put your instructions on the wiki at appropedia?

It would be easier to refer to it, add further details and improvements (Andrea's), and maybe someone will add video (hint, hint).

If allowed, I'd have to find the instructions themselves, but that's another matter.

And of course I don't know when exactly I'd be able to do the "wikification" - hopefully soonish.

Lucas

2011/7/19 andreas <andre...@gmail.com>

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[Lorin Basche]

So I'm almost done with construction. I chose to connect all the wall
panels together, and yea the block is a bit large, but nothing
unmanageable. I can still carry it by myself which is all that matters
for me =P I finished one of the roof pieces last night by myself in a
matter of 2 hours in my living room, with really only enough floor
space for one 4x8 attached to one triangle piece at a time and just
folded it on itself every time I finished a hinge. Worked like a
charm. I'm finishing the prefab today and I'll take some pictures when
I move it outside to see how everything fits, and I'll take more when
I have my camp mates come over for our test build before the Burn. I
definitely second andrea's question about tape anchors though. What is
the best pattern to drape the tape anchors over the yurt in
combination with a rope halo?

On Jul 18, 11:55 pm, Lucas González <lucas.gonzalez...@gmail.com>
wrote:

> Documaniac mode = "on"
>
> Dou, can I put your instructions on the wiki at appropedia?
> It would be easier to refer to it, add further details and improvements
> (Andrea's), and maybe someone will add video (hint, hint).
>
> If allowed, I'd have to find the instructions themselves, but that's another
> matter.
> And of course I don't know when exactly I'd be able to do the "wikification"
> - hopefully soonish.
>
> Lucas
>

> 2011/7/19 andreas <andreas...@gmail.com>

[dou]

Great news, Lorin! Let us know how it goes. You must be more skilled than I am, it took me several hours to bisect, tape, and hinge up half of a hexayurt by myself.

Lucas, I had already added the link to the instructions from the H13 page, but you're right, it's better to inline them at the wiki page. I took a stab at doing that. Everyone should feel free to contribute to the H13 instructions I added to http://www.appropedia.org/Hexayurt_H13#Alternate_design. 

-dou

[Lucas González]

Great Dou! (I love wikis.)

I'm just building a few models (from 14cm x 28 cm panels, 3 mm thick, and all shiny) for a computer party here in Tenerife.
Let me see if I can stay awake long enough to build all I want to build.

Lucas

2011/7/19 dou <ble...@gmail.com>

[Lucas González]

On the subject of tension rings - can a chain be used, taken off when crossing the door, then placed back in place after?
If the door opens towards the inside and it's very windy at that moment, you can still bend your back and go below the chain.

These yurts start to look like they have a watch-with-chain, like those you keep in the pocket of your waistcoat (or vest).

Lucas

[andreas]

My plan had been JUST tape anchors... not sure how you'd do the rope halo on an H13... but.. I'm open to suggestions! 

I may have some pictures of the initial build process.  We did have someone taking iphone pics, but I'm not sure yet if any will be helpful.
If they are, I'll put them up.

-andreas

[andreas]

Here are a few cell phone pics... they might be helpful...

http://s11.photobucket.com/albums/a180/andreas970/H13%20Build/

-andreas

[Lorin Basche]

So I finished prefab 5 minutes ago, and I hit a stump that has me
wondering what I did. I was under the assumption that when
construction was complete on an H13 that there would be 2 panels with
the logos on the outside, and I finished with only 1. I sat there for
a while comparing my two roof pieces making sure that I had all of my
pieces on correct and I did. Was this simply a misunderstanding on my
part expecting to see 2 panels facing out but really only having one,
or did I in fact do something weird? Oh and dou, my panels were
already bisected and had their edges sealed, I was simply doing tape
hinges, thats how I managed to do it so fast. =]

[Lucas González]

I think it's only one. See http://www.appropedia.org/Hexayurt_H13 Figure with "Step 4". Only one "Foil".

It's been suggested that H13's should be built in pairs. ;-)

Lucas

2011/7/20 Lorin Basche <lorin...@gmail.com>

[and 970]

You did it right!  It's only one logo-out.

-andreas

[Alejandro]

Just finished our H13 model and it came together pretty well. We're
building the real thing tomorrow in my driveway, driving up Sunday.
I'll be at 7:30 and E, with "Camp New Year's Eve".

Burnin!

-Alejandro

On Jul 20, 5:06 am, and 970 <andreas...@gmail.com> wrote:
> You did it right!  It's only one logo-out.
>
> -andreas

[Jean-Marc Arsan]

We build our semi-folding H13 (using Julie's instructions) today (it
took us around 6h to build it, 45 min to assemble it and 2h to wrap it
and strap it to our car's roof).
We will be using a rope halo but I'm not really sure as to how many
cords we should use and where we should put them. if you're interested
and want to help us put it together ( :) ) we will probably arrive
around 4-6AM, our camp is at 4-B.
Vinay/Julie , thanks again, I'm a big fan!

Regards,
Jean-Marc

PS: I can send you some pictures of our hexayurt if you are
interested.

[Alejandro]

Hello H13'ers, just making an addendum to the subject title here.

So we relatively successfully built and broke down an H13 at BM and got back home Sunday.  Alas, the winds were so mild there this year (along with temperatures), that I would say this was not a fair year in which to truly wind-test the H13.  So imo the jury is still out on that, unless someone ends up testing the H13 in a high-wind situation elsewhere.  We took a risk and only used tape-downs to pvc piping, then tied those with rope down to rebar.  We did not make a rope halo, so perhaps we got lucky.

(@Julie Danger it was SO nice to meet you at the hexayurt happy hour, you're even more beautiful in person!  Jake and Mars the H13'ers from Seattle, sorry I missed your wine-tasting, I was exhausted and fell asleep back at my yurt and didn't wake up till 9pm).

We built a 2-section roof, as we did with the base.  However we must have done something wrong during the tape-hinging, as we couldn't get the 3rd panel from one of the base sections to fold over onto the other 2, so we just cut the tape in order to stack them all tightly and wrap them in a tarp because at 10pm in the dark and exhausted, we still had to tarp-wrap them, sandwich between two 4x8 plywood boards, then tie everything down properly to the roof rack.  Tip:  If you have/can rent a big enough vehicle/trailer so as to not have to make the tarp/plywood sandwich and then figure out all the knots so as to tie that mf down (and down TIGHT), I would highly recommend that, as it's a lot of work otherwise, and if you're not that great at knots and rope, you could knock off an easy 2 hours of set-up, and another 2 at break-down.  From all that pulling rope knots tightly, if you're not used to that sort of thing (and you aren't in your early/mid 20's anymore like me), you will be sore the next day, I can guarantee that.  

The H13 was a great refuge against (the mild) wind, dust and sun, as well as the cold at night. In fact it was really warm at night, too warm the first few nights. It also got warm during the day too, warmer than I'd expected.  I was told that because of the accumulated heat in the ground (prior to placing the yurt there), the heat has to slowly rise out of the ground, thus additionally warming the yurt the first few days until the ground reaches a cool temperature again, and that heat will rise into the yurt obviously.  It seemed to make sense as by the 3rd or 4th night, I finally started to need to use my sleeping bag, though it was still too much to be inside of it.  I simply laid it over me like a blanket and that was suffiicient warmth for me.  There were 2 other people that shared the yurt with me just fyi. 

By the 2nd day we realized that a window was definitely going to be necessary.  The tape hinges let in enough light to see during the day, but the window's more important purpose was to allow for cross-breeze or flow through the yurt.  Luckily I'd brought 2 furnace microfilters with us.  We simply cut out a hole the shape of one, then taped it in with the foil tape on both sides.  It seemed to be a high quality filter since it allowed breeze to flow through, but very little dust.  The dust will start to clog the filter eventually so you can either blow, brush or sweep the dust away from the window/filter from the outside. 

Opening the door will let the cross-breeze flow through nicely.  Up till then, the wind would blow the door back and forth, almost shut at times.  But once the window was installed, the door would blow around a bit but would mostly stay wide open.  Thus, with only one window, you really need to have your door open for cross-breeze.  Installing a 2nd window would allow you to have cross-breeze while also keeping your door closed.  Not as much cross-breeze as having the door open, but some nonetheless.  We never installed a 2nd window though, as it was a hassle dealing with moop from cutting out the window in the polyiso foam panel, so I left it with just 1 window.  In that heat though, I would recommend you install 2 windows, and install them at home where it's easy to deal with moop.  Though one interesting adaptation I did see at BM this year was that some yurts had some of those heat vent stacks installed into the ceiling, one even had one of those spinning heat turbine things on theirs, which makes lots of sense actually.  That could avoid the need for a 2nd window.  Structurally, it could be argued that windows to a certain degree, do weaken the panel's and therefore yurt's structural integrity. Then again so could a vent stack, but a vent stack is a much smaller hole than a window would be for a furnace panel, though the furnace panel would be installed in a side panel, not a roof panel.  And a hole in a roof panel would have to be taped well in case it rains.  

As for our door and structural integrity, we did not do a tall door as unlike ^Lorin^, the 3 of us are somewhat vertically challenged (short), so we didn't need a tall door, but we wanted the extra room overhead all the way around inside the yurt, and the extra headspace means extra cooling space for heat to rise.  Security was minimal, as all we did was poke a round hole through the door, threaded a piece of rope through it and tied a knot on either side, that became the door handle.  Like many of you, we simply trusted nothing would get stolen (and nothing was stolen I'm happy to say). And it was tape-hinged along one side vertically so as to swing open and closed just like a regular door, i.e. we did not do the "cat-flap" style door.  So if you don't mind keeping the door to under 4', then you don't completely cut through one of the base panels, nor do you cut into the 2nd panel above the base panel in order to achieve the "tall" door, thus retaining a greater degree of its original structural integrity.    

As for the floor, we taped a 16' x 20' tarp to the outside of the yurt.  So kind of cupcake-style, but my friend used the nice expensive bifilament tape instead of nice cheap gorilla tape.  Oh well, water under the bridge.  The one mistake we made with taping the tarp floor up was we taped over where the window eventually needed to go.  So I had to cut, pull and "throw away" (i.e. carry back home with me) perfectly good tape, expensive tape, which also pulled away the foil wrap from the panel, and that sucked.  So I had to use foil tape where the panel foil had ripped away, then re-taped the tarp onto that outer wall but obviously below the new window.  So again, this speaks to doing the window at home beforehand, and maybe roughly plan out how you're going to lay your tarp out at home before getting to the playa and trying to find the best position amid the heat, dust and wind (and hopefully not at nighttime).

Things I would change:  I can't really speak to the rope halo/tie-down dilemma because the wind didn't cooperate (though I'm not complaining).  I would install at least 1 window at home and not on the playa, maybe even 2, and definitely before taping the tarp floor up.  I might try out that heat turbine vent thing next time.  I hate tying down that huge sandwich on top of my car.  It also makes for really shitty mileage because of that 14 inch high 4'x8' brick you have strapped to your roof, completely ruining all aerodynamics.  I normally get around 24 mpg in my volvo wagon, instead I got about 18-19 mpg. Granted the car was also fully loaded on the inside as well as carrying one other passenger (3rd yurt member arrived and departed separately), regardless though it was a buttload of gas.  Honestly though I can't say which contributed more to the decrease in mpg, either the weight on the inside, or the oversized brick on the roof, since the yurt doesn't really weigh much at all. But at 65-70 mph, it's hard to know how much extra gas the tarped foam brick plywood sandwich on the roof is consuming wind-resistance-wise.  Oh, and don't share your yurt with someone you don't really know that well.  And absolutely make a basic ground rule - SHOES OFF BEFORE ENTERING THE YURT, no matter how short a time period you're coming inside for.  Make sign and stick it outside if you have to.  Because some people, even smart, educated, intelligent people, can be really fucking clueless sometimes.

Thank you to all here for your sharing, tips, concerns etc.  They were all of great value.

@Julie Danger, I have video and pics.  How do I send them to you ?  By the way I forgot to sign the board at the hexayurt happy hour  :-(  

-Alejandro