Steep Roof, Large Ring?

[BlossomMerz]

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.

[Surely Yurts - Steve]

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!

[BlossomMerz]

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

[jeritchie]

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

[BlossomMerz]

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

[jeritchie]

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

[BlossomMerz]

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.

[BlossomMerz]

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

[Woodyrock]

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

[bss]

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.