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Steep Roof, Large Ring?

BlossomMerz

New member
Hi, there!

I'm brand new to this forum, having sought it out as a place to learn as fast as I can. You see, I am taking the leap in a big way and building a platform and yurt this spring to serve as my weaving studio and residence.

I've read the books from Laurel Nest, Paul King, and others, so I've got a whole lot of construction ideas, but no practical experience.

For various reasons, which I'll explain if you like, I would like my roof to be very steep, about 45 degrees, and my roof ring to be large. (That one's easy to explain: lots of light.)

I'm thinking of standard 1x2 fir for the rafters and walls. 12' for the rafters and 10' for the walls with holes spaced 9" apart.

Here are my questions...

Is there any engineering reason not to make the roof so steep or the ring so large?

With 72 rafters, is a 12' 1x2 strong enough to hold up the roof, including a wool insulation layer and a fireproof rubberized "truck tarp"? If not, would a 2x2 work?

If I upgrade the rafters, will the walls be strong enough to hold it all up?

Thanks for any help y'all can give.




PS: The rendering was done in Google Sketchup. Don't let the slick appearance fool you. I spent years as a 3D software developer, but have no experience building yurts.
 

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Yurt Math: Proportion

Hi,

The pitch of the yurt roof should be proportionate to the diameter, for strentgh and beauty. Your pitch looks too steep at this point.

here is a link to some yurt math and an online calculater:

SimplyDifferently.org: Yurt / Ger Notes

Should use larger than a 2X2 for a 12' span especially for snow load. But, I have seen more traditional yurts that simply use 2" sticks with the bark skinned off as rafters. That is usually for a shorter span though, closer to 8'.

A healthy dose of patience with a dash of zen should go a long way to help whilst teaching yourself this new skill!
_____

I would also reccomend considering a used yurt. It may actually be cheaper and less time consuming to restore an old yurt rather than building a new one from scratch (think of tools you'll need to buy and all other expenes). In the pac. northwest, you should have many used yurts available on the market.

Cheers!
 
Used yurt? Smart!

Thanks, Steve!

I hadn't really considered that yurts are popular enough that I could find one used. When I started fantasizing about living in one, I could find very little on the market. Recently, I priced the new ones from several companies and they're way more than I can afford, even considering the peace-of-mind and time savings that comes from letting someone more qualified do the engineering and construction.

Especially with the constrained time frame, I think that looking into used yurts is a really smart idea. Thanks for the tip.

In case I do go through with building my own, what do you mean when you say that the pitch should be proportional to the diameter? I know that 45 degrees looks too steep. The only yurt I've physically worked on had a 32 degree pitch, which looks like the norm from the hundreds of photos I've drooled over.

Thanks again for your help!
Blossom
 
I have to agree with Steve. Stay with the industry standards for 'code-compliant' yurts - 30 degree roof pitch and standard ring sizes. This way you can build the frame yourself and purchase a new cover if necessary. If the ring is a standard diameter and back-cut, you will be able to purchase a standard acrylic skylight.

12' span should be at least 2x4 of a known hardness wood (e.g. not SPF). Depending on your location (snow load) you should probably consider 2x6 rafters.

10' Lattice walls are quite a challenge, you might consider 7' walls and put them on top of a small pony wall.

jer
 
Thanks, jer,

I had noticed that most yurts were pitched at about 30 degrees, but I had never heard of it as a standard. I think I need to take a step back and look for information about the standards and traditions before I go too much further out on a limb.

I've only got a budget to build my yurt once, so I'd like to do it right. I'll come back and update as I learn more.

Thanks again!
Blossom
 
Blossom:

I have just completed a traditional Ger for camping. Being for camping, it is small, 4.5 meters in diameter, but built pretty close to the Mongolian time tested design. My outer cover is an acrylic canvas, the felt insulation is layered disaster blankets (they are felted synthetic/wool), and the inner cotton lining is hotel quality sheets (less expensive than yard goods). The wall slats are white oak, whilst the rest is vertical grain Douglas Fir. The steep pitch you envision would collect heat, making the living level cold. In a traditional Ger, the walls taper in at the top, which provides more stability, and strength.
Woody
 
Fyi there is a 30' pacific yurt out near coos bay I think, for sale for $5k obo. A tree fell on it so It needs a new dome and some rafters and fabric repair. I am unclear on the extent of the damage. Haven't talked to the owner because I don't have the need for any more yurts at this time, but might be worth checking into. They've been trying to get rid of it for some time so you could probably get a really good price. Sounds like a good fit for someone in your situation. Just a thought

Ps Ive seen 2 or 3 20-24' pacific yurts on craigslists in oregon in the last few weeks all in the $5k range.
 
Woodyrock, thanks for the info about your yurt. It sounds really nice! I know that the heat will rise. I've got three things in the plans to deal with this: a ceiling fan, a second level, and a quilted drop ceiling. Part of the reason I want it so tall is to put in a loft and have a small second story. My original question had to do with engineering. I wondered if there's any structural reason why the roof can't be so steep. Does it catch wind, cause the ring to wobble, put more strain on the walls, etc. Based on the advice I've gotten, I think that I'll stick to standard dimensions for my first yurt. Maybe down the line I can design and build a tall one like this, but it seems like too much for my first one.

bss, I've been trying to contact the owners of that yurt out in Walton, but had no luck. I've just got a craigslist posting to go by. Do you have better contact info or another source for this listing that might get the message through to them? I've seen the $5,000 24' yurt listings, too, but so far no luck snagging one. I'll keep at it, though. Since many of them include a platform if I do the work do disassemble and move it, this seems like a very economical alternative.

And, just putting it out there... I'm willing to pay around $5,000 (and a little more if need be) for a used 24' or 30' yurt and platform, preferably from a reputable manufacturer and do all of the work to disassemble and move it from anywhere in Oregon, southern Washington, or northern California. I can show up with a moving truck, crew and tools in early March.

Thanks everyone for all of your help.

Blossom
 
I think you are going the right route Blossom. I would love to see your tall yurt if you ever decide to do it. I just think a standard design is better for your FIRST yurt. :) It would be great if your design worked. I love different designs. :)
 
Just a note - I am not sure if this is an 'official' standard. It is more of an ad-hoc standard that has grown up based on a choice made forty years ago by the first builders of 'North American' yurts.

Several times a year, I will get people calling our company with a story like ' I built my own frame now I would like to buy a cover. OR can I buy a acrylic skylight for ring ' The first questions are what is the pitch of your roof and the outer diameter of your ring? Many people copy the Mongolian design and use a 22.5 degree pitch. Unfortunately I can't supplied parts that will work on those Yurts.

If you want to build your own Yurt - Go for it. It is fun and rewarding and you will learn a bunch.

Good Luck

jerry
 
24' Yurt Measurements?

Thanks, everyone, for the encouragement. I did restore a damaged 16' yurt a few years ago, so I'm not a complete newbie to this. I've just never designed and built one myself.

On the topic of standards, though, I now want to design mine to use an off-the-shelf acrylic dome and roof cover from Pacific Yurts. Can anyone point me to documentation of the sizes I should shoot for to make this possible? Should I just buy those parts first and design the whole thing around direct measurements?

Specifically, I would like these measurements from a 24' Pacific Yurt:
- Dome diameter. Folks have said 48". Is this the true diameter of the bottom of that dome? I'll size the roof ring to this.
- Roof pitch in degrees. (Top of the rafter at the outer wall and the ring are good enough. I can calculate the pitch from that if I need to.)
- Roof pole size. What's the cross-section shape and size? 2x2? 2x4? What length?

I'm close enough to them that I might just take a trip up there. I have to wonder, though, if they would be pleased to have a "tire kicker" show up and take measurements in order to duplicate their design. Even if I'm going to buy a bunch of parts from them, it seems like they might get a little miffed that I can't afford to just buy a whole yurt.

Thanks again for any help y'all can give.
 
Oh, hey!

I finally found the page of PDF documents on the Pacific Yurt website. Pacific Yurts-Downloads

It gives me most of the measurements that I need, I think. But then there's a statement in one of the files... "NOTE: Pacific Yurts does not provide parts for structures that we did not manufacture." This is from the Top Cover Order Form on the downloads page.

Has anyone actually bought domes or covers for homemade yurts directly from them?

Blossom
 
Blossom:

You might just as well sew, or seam weld your own cover. Since you have the skills to build the frame, the cover should not be that much of a task for you. Whilst, I have not sewn a large cover, I have however sewn boat sails that were much larger. Once the fabric is rolled, each new panel fits under the machine arm, and if you have a good table set up the whole thing will slide right through. I used seam sailmakers tape on all my seams, which serves a twofold purpose. First, it holds the seam together whilst sewing, and secondly, it waterproofs the seam. It is advisable to use a thread oiler to lessen the needle gumming.. Oil the bobbins too. That said, some cover material can be glued, and does not requires sewing.
Woody
 
I agree with Woody, but if you absolutely do not want to do that, I believe Colorado Yurts sells parts. I have also heard that Yurts of America plan on opening a parts department any day now. :)
 
You're both right, of course. I have the equipment to build the roof and wall covers myself. Production sewing is part of my business as a weaver, after all.

I was just continuing with an earlier idea that I should go with "standard" measurements so that I can buy parts off the shelf. I guess it's just the dome that I'll need, then, unless I stitch something out of vinyl. I'll modify my design to include a 48" diameter ring and a 30 degree pitch. I'll worry about the dome later on.

I really do like the aesthetics of Paul King's detailed hardwood crown and his tapered and chamfered roof rods. As long as I'm building this thing myself, I think I'll do some extra leg work to make it that kind of beautiful.

These plans could all change if a used one shows up, but I'm going to plan as if it won't.

Thanks for all your feedback.
 
And, the idea of "standard" went out the window for me when I found that Colorado Yurts domes are 5' wide instead of the 4' that I believe to come from Pacific Yurts. I'm going to design around the 5' ring because I want as much light as I can get.

Living and learning!

Blossom
 
I know this is an old thread. I wanted to add my .02. A traditional Mongolian yurt pitch is quite shallow. 22.5 degrees is what I consider to be perfect for a 5' 4" wall height, from a visual standpoint. The pitch on my yurt is about 24.5 degrees, and very slightly too steep. When I laid out the pitch, I wanted a bit more clearance to the bottom of the roof ring. In hind sight, 22.5 would have been best. There would be a bit less area to heat, and as it turns out, headroom isn't an issue at all. This is all visuals. I like the trad Mongolian yurt look.
 
I would guestimate that the majority of the yurts put up in North America are in the 20-30 degree pitch, in Mongolia few are over 24 degrees, and they big ones.

The yurt calculator posted earlier here is excellent. Jafo and Bob also posted on other threads about using the Simpson fasteners for attaching rafters to the tono and the walls. For a 24' yurt in OR I for sure would want 2 X 4s at least for rafters. And at least four, or more posts in the wall, besides the cable around the khana. If you put in a modern window its frame is also an excellent way to include solid posts.

There is a huge amount of information here, free for the reading. You can put two good posts in the khana from the door frame, 4 or more from a couple windows. That way in a 24' dia yurt you have a good anchor to brace against wind and downward forces.

Happy researching !
 
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