For the wooden slats, I would love the opportunity to use something local and renewable. But I can't think of anything. We don't have coppiced anything here like they do in Europe. We have Big Leaf Maple and Alder in our woodlot, both fast growing, but no way to mill them. Also, I don't know how they stand up to being yurt walls - are they super-heavy? Do they twist and complain in the weather? I'll keep looking around for something that might work, but nothing really jumps to mind.
Second choice is to use reclaimed materials. There are a lot of old shipping pallets about, but the longest I know is under 6 foot long - not enough. To find enough pallet wood, long enough and in strong enough condition... doubtful. So, perhaps there is some other source of wood that I can reclaim. What I really need is a friend tearing down an old barn, now that would be awesome. I'll keep a lookout, but again, I have my doubts I can find anything.
Then again, that is kind of the point of the blog - to get the word out there that I am looking for something... maybe someone out there has just the thing I need, wasting space in the back of their shed... maybe.
Until I find a source of local renewable wood or wood that I can salvage from imminent destruction, I am going to plan this as if I am using store bought lumber.
The major downsides of using store bought stuff is that it isn't necessarily harvested or processed in a sustainable way. Also, it costs money. But if I can't find a better solution, it will have to do.
A yurt wall (called a Khana) is made of wooden lattice that can be folded up for easy transport, and extended into a round shape, held together with tension band and roof slats. It's really quite clever. But how to make it?
How many slats? How close together are the slats? How long? How many sections? What kind of wood? How to attach the sections together?
From what I can discover is that there are many right answers to these questions. Whenever faced with a challenge like this, I like to consult the local library (even at the risk of the dreaded overdue fine). Here's a few snippets that I found concerning constructing yurt walls.
Yurts; Living in the Round by Becky Kemery
This book is a great inspiration for yurt shaped structures, with a sampling of traditional yurts and methods as well. Though limited practical data on how to build different sized yurts.
- The wooden structure is traditionally made from willow or fir.
- For both Mongolian and Turkish Yurts, "each wall unit is made up of ten to sixteen whole willow rods (or split wooden laths) that run in each direction; shorter rods make up the corners. Holes are drilled in the rods at precise (but nonuniform) spacing with either a hot iron or bow drill. Then wet rawhide strips are knotted, pulled through the hole, knotted again, and cut. As the hide dries, it tightens and draws the slats together."
- Interesting bit about there being a top and bottom to the traditional wall of a yurt. "The crisscrosses at the top of the wall are called 'heads' and at the bottom they are called 'feet'. Usually the foot sections are longer than the head sections to provide greater traction and stability for the yurt and to allow for wear or breakage over time."
- The traditional mongolian yurt has five wall sections, but most yurts have four. Some can have a great deal more depending on status of owner and the yurt's use.
Tipis & Yurts; Authentic Designs for Circular Shelters by Blue Evening Star
At least I think that's the author's name. It is a very beautiful name.
The book includes history, inspiration, as well as construction methods. From what I can tell, the instructions on how to build yurts are a modern interpretation on traditional designs - traditional shape and materials, with a few changes to meet the demands of Western lifestyle (for example, taller walls, steeper roof pitch). Here's what they have to say about building the wall frame:
- The design in this book takes advantage of modern Western materials like metal bolts, brackets, and wire cable.
- Recommends number one kiln dried douglas fir with no twists or knots. 1" by 2" for the wall and the same or 1" by 3" for the roof rafters. Failing douglas fir, any "other comparable lumber (preferably close grained) is acceptable."
- talking with The Captain about this, this kind of wood isn't the most eco-friendly. Douglas fir of this quality usually comes from old growth forests, which is not a renewable resource. I'll use something other than number one douglas fir.
- The wall laths are 6 foot long, and held together with metal bolts.
- Two or more wall sections.
- The holes are drilled - starting 4 inches in from one end, and every 16 inches along from there. 5 holes total.
- Excessive emphasis that all the laths are exactly the same length - 6 feet.
- A chart is included with different yurt diameter size and materials needed. They don't include a 16' yurt, so I looked at what was needed for the next size up - 18 foot.
- 3 wall sections with a total of 120 laths (if I read this correctly)
- 300 joins (300 bolts and knots, 600 washers)
- cable length (circumference) 60 feet
- Hub (roof center) diameter 3 feet
- 18 rafters
- rafter length 7'6"
- I'm having trouble determining if these numbers include the short laths at the end of each wall section. Though perhaps they aren't making a 'finished' wall section. Instead leaving the laths long like fingers that will be bolted together when the yurt is assembled.
- Instructions and pictures on how to assemble the laths into a wall frame.
The House that Jack Built; Circle Houses; Yurts, Tipis and Benders by David Pearson
Another inspiration book with stories and photos of modern and traditional designs including a nice series of photos on traditional felt making. Tiny section in the back on how to build these portable structures.
It's a really short paragraph on how to make the walls, so I'll just quote it here:
WALLS To make the lattice wall sections (khana) use wooden rods, whole or split in half as slats. Traditionally these are cut in winter (coppiced) from willow trees or hazel bushes [it's a UK book], but any sustainable straight-growing or recycled wood is good. Drill equally-spaced holes along each slat and connect all slats tightly together using string or small bolts. For ease of transport, the completed khanas can be folded. Once the khana is erected in a circle, a canvas, rope, or wire 'tension band' must be tied around the top to contain the outward thrust of the roof.
It gives no length or specific measurements. Just general requirements. The whole how-to section is sparse like this. But actually, it's the most inspirational instructions of them all. Sure my brain craves precision and a paint by numbers approach to making a structure, but I can often do better with a simplified set of necessary and sufficient conditions that need to be met.
Build Your Own Yurt; A complete guild to making a Mongolian Ger by P. R. King
A pdf booklet I found at this link here. And a very good one at that. Obviously written for the UK market. Besides the prices being in pounds, it also makes reference to sustainable materials that we don't have on this side of the pond.
Here's what King has to say about making the wall frames:
- For a 16 foot yurt, the walls are 5 foot high, the total hight of the yurt 8 feet, wall polls 6'6", and the roof poles 6'. The crown 3 feet across.
- Willow or Hazel rods about an inch in diameter (so round ones like what grows naturally in a coppiced forest) cut from Oct to March. Bark removed or not.
- Green oak batons 1/2x1 and 1/2 inch also work.
- Hole spacing: starting 4 inches in at one end, space the holes 9 inches apart from there. The final hole being 2 inches shy of the end.
- Uses a string to tightly tie the laths together.
That's about it. There are a few other references online, but not as much detail as the above.
The questions I need to ask myself are:
- How many rods do I need for the walls?
- How close together am I going to put the rods/slats/laths?
- How tall a wall do I want?
- How long are the slats?
- What angle do I want the laths in the wall to stand when set up?
- What am I going to fasten them together with?
- What material am I going to use for making the walls?
- How much is it going to cost me?
For the first one, I have no idea. I'm going to guess more than 100, probably closer to 150 separate pieces. Need more information before I decide exactly how many.
Second - good question. I've seen photos of yurt shaped structures where the rods are at least 2 feet apart. Though most seem to be less than 10 inches apart. I guess the local environment has some say in this. We get wind, but not the huge storms. We get snow, but not every year. When the snow comes, it comes heavy, sometimes we get three feet or more! But like I said, not every year. I guess what materials I use will determine how close the slats are, but assuming I'm buying strong aged lumber, about 1 foot apart would be sufficient.
How tall at the wall? At least 5 feet, 6 is better.
How long are the slats? Probably 6 foot-ish?
What angle? No idea.
Something to fasten them with - actually I like the idea of raw hide ties. This is something I can make on the farm with the hides of animals, a part that would otherwise be wasted.
Materials for making the wall? Preference would be renewable resource, but since we don't have coppiced wood here, my second choice is reclaimed wood. Where to find reclaimed wood that is straight, strong, the right size and/or is soft enough to be worked with tools and doesn't have chemicals that will aggravate my health issues.
Failing that I'll need to buy it. Maybe some 2x4s and rip them on the tablesaw. Assume one 2x4 gives 3 slats, times 150 slats needed = 50 2x4s at whatever price they go for. Local DIY shop sells them for $3.05 per regular old construction grade 2x4, plus 14% tax. I'm overestimating the number of slats needed because there is bound to be things break when I learn these skills.
So how much does that cost?
50 x 3.05 = 152.50
Plus saw blade for ripping the wood down to size about fifty dollars = about $200
plus 14% tax = $228
And because things are never as low as one estimates, let's round it up to $250 to cover travel expenses, &c. It would probably cost more for more suitable wood, hopefully less for reclaimed wood... but here's a good starting point.
Assume I'll make the rawhide this winter from some sheep skin for tieing the slats together - $0 dollars.
That gives us an estimate of $250 for the wooden wall construction.
Skills needed to make the wall
- choosing the right wood for the job
- ripping and/or planing it down to size
- reclaiming or refinishing old wood (if I can find something suitable)
- drilling holes
- making rawhide
- tieing knots
- counting and measuring
When you look at it like that, it doesn't seem so daunting anymore.
Update: on the cost estimate here - now $150 ish.
Update: On further consideration and after looking at a few shops that sell wood, I'm going to up the budget back to $250.
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