There are two components to the roof on a yurt. You have a roof ring and rafters. Like all yurts, there are many ways to build one, and most of them work fairly well. You can go for a large diameter ring or a smaller diameter one. The diameter of the yurt and the length of the rafters both factor in to the ring size. Another thing to consider is that the larger the ring diameter, the more rafters you will end up with.
When choosing your design, roof pitch is very important. The steeper the roof is, the faster the water will run off of it, giving it less time to soak through. All canvas will leak if it stays wet enough for long enough, so you don’t want your roof to be too flat.
When I set up a yurt, I usually shoot for at least a 3 foot rise on a 16 foot diameter. Anything flatter, and you are asking for leaks.
You can make the ring small, about 30 inches across, or larger, I made mine 42 inches. There’s no right or wrong answer here. Roof pitch and rafter length factor in as well. I try to keep the overall rafter length to 8 feet or less, since 8 foot lumber is easy to come by.
One of the biggest mistakes that I have seen in yurt design is not setting the rafters deep enough into the ring. If the rafters are too shallow, they can fall out, especially in a storm, causing the whole roof to collapse. I have even heard of the ring spiraling around and falling in.
To figure out the roof ring size we will need, I will go with 8 foot rafters for the 16 foot yurt. Subtract 4 inches to allow for inserting one end in the ring, and the other end hooking on the walls.
96 – 4 = 92 inches
We will go for a 3 foot rise (36″) or higher in the ring from the top of the walls.
First we need to calculate the difference between the diameter of the yurt and the ring.
Let’s start with a 36″ diameter ring and see how much of a rise we will end up with.
The diameter is: 16 x 12 = 192″
192 – 36 = 156
156 / 2 = 78
= 48.78 inches rise
This is a nice steep roof that shouldn’t leak too easily.
There are probably as many door designs as there are people who have built a yurt. Everyone has their own unique variation, and no two are alike. The most important thing is that the door frame has to join the ends of the khana and complete the circle.
Some door frames are rigid, some can be disassembled for transport, and some are flexible. The one thing that they all have in common is that the uprights are angled to match the curve of the khana. Most are held at a fixed angle, while my design allows them to pivot, so they are always at the proper angle.
You will need 4 2x4s as tall as your khana walls will be. In our case, that is 6′. You will also need 2 pieces of 1×4 cut 6″ wider than the door frame will be. Our door will be 30″, so cut 2 pieces at 36″. The last item will be a 5/8″ oak dowel cut into 4 6″ pieces.
You will need to cut 2 notches down the length of the 2x4s 1 1/2 inches deep by 3/4″ wide. This will make a groove for the khana to rest in when assembled.
Glue and screw the pieces together so that they look like the picture above.
Drill a 5/8″ hole about 3″ deep in either end, put some wood glue in the hole and tap in a dowel.
Next, measure 3″ from either end of each 1×4 and drill a 5/8″ hole centered. This is what the door frame looks like when assembled. You can drill a small hole in the end of the dowel and insert a clip to keep it from coming apart.
So by this point you have cut and drilled your khana slats.
First you should stress test them. Khana slats bend a bit, and it’s better to weed out the weak ones now. You will need 2 blocks about 12″ tall. Place them about 7 feet apart. Put a khana slat between them and press down until the center touches the floor. If you hear a crack or it breaks, set it aside. You can use those for the short ones on the ends.
Now it’s time to put it together. But before you do, paint or stain them to your liking.
Now let’s lay out the slats. Take your original count and divide by 3.
86 / 3 = 28.66, so we go with 28. Add 2 extra to one pile. You will be Assembling 2 sections with 14 diamonds wide (half the number of slats), and one with 15. The important part is that you will end up with 3 sections roughly the same size. It’s not all that important that they be the same length, as long as you have a total of 43 diamonds wide.
The end slats will need to be cut to make a straight edge. The cut off ends you will use on the opposite side. It takes a little playing with to get it, but it should make sense when you get there. The ends will be cut to 2, 4, 6, 8 holes, and 3, 5, 7, 9. You need 2 of each per khana section, so 6 of each. See the photo above for a visual.
One of the most time consuming parts of the project is making the khana (wall). The khana is basically a huge baby gate. It collapses down for storage.
Traditionally, the khana is about 4 feet tall, but that is not very practical when you are closer to 6 feet tall. You can make yours any height you wish to, but I will assume that you will be going for a 6 foot khana.
The first thing that you will need to do is figure out how long the slats need to be. The math for this uses the pythagorean theorem. I won’t bore you with the details, so here is the math involved. You start with the height of 6 feet.
(6 x 6) + (6 x 6) = 72
Take the square root of 72 (use your phone calculator) to get the length of your khana pieces.
Square root of 72 = 8.48 feet
Next, we need to figure out how many diamonds there will be. I recommend 10 inches on center for our project.
If your walls are a different height, subtract 4″ from the slat length and divide by 9. You might need to play with this number. Any size from 10-12 inches on center will work just fine. Find the best number for your project that gets you a size in the 10-12 inch range. Ex: 6.5 foot slats would work best with 7 at 10.5 inches.
For diamonds 10 inches on center, the width from tip to tip is: (10 x 10) + (10 x 10) = 200. Get the square root of 200 = 14.14. I’ll round to 14 inches.
From part 1, we know that the khana will be 47.75 feet, or 573 inches. Divide this by 14 to get the number of diamonds.
573 /14 = 40.92. Round up to 41.
Now, you will want to break the khana up into sections to make it easier to carry and set up. I recommend 3 sections. In order to assemble the khana, you will need to overlap at least one diamond per section, so we’ll add 2 diamonds to our count to end up with 43 diamonds total.
Multiply the number of diamonds by 2, and add 2, this is the number of full slats that you will need.
43 x 2 = 86 +2 = 88
Now, let’s talk about materials. You will need to buy lumber and rip it into slats. Don’t buy pine, you want a harder wood like poplar, which is fairly easy to come by. 2×4, 2×6, etc. lumber is easiest to get. I’ll assume you can get 2x6x8 poplar. Yes, we calculated 8.5 feet, but getting 10 foot poplar is not easy. It’ll just shorten your walls by a few inches, not a big deal really.
A 2×6 is actually 5 1/2 inches wide. You will be ripping 5/8″ slats, and the table saw blade will eat 1/8″ each cut, so you need 6/8″ (3/4″) per slat.
5.5 / .75 = 7.33 slats per board. Round down to 7.
Divide the total number of slats by 7 to get the number of boards you need to buy.
88 / 7 = 12.57 round up to 13.
Now, there will be knots in the lumber. You want to pick the boards with the least amount of knots as possible. Knots are weak spots, the slats will break at the knots. Also, there will be natural weak spots in the lumber, so I recommend cutting 25% more slats than you need. I’d buy at least 17 boards.
On the last yurt I built, we cut about 120 slats, and about 25 broke when we stress tested them prior to assembly. This left us with about 10 good spares for future repairs.
To cut your slats, set your table saw at 5/8″. I recommend a friend to help feed the saw. The finished slats will be 5/8″ x 1.5 x 8 feet. If you need shorter slats, shorten the boards before you rip the slats.
Measure 2″ from one end to mark your first hole, then every 10 inches make another mark. If you did this properly, your last mark should be 2″ from the other end. Now is your chance to fix the size of the diamond if you need to. Write down your final measurement. You’ll need this later when you drill the holes.
There are several ways to put the khana together :
There are pros and cons to each of these systems.
Rivets are fairly easy to use, and are very secure. They won’t loosen up over time. The downside is when you break a slat, you need to drill out the rivets on the broken slat. 1/4″ rivets should work. There is no forgiveness for sloppy hole spacing.
Bolts are the simplest to install, but the nuts tend to come loose, so you will need to keep some spares handy. They also don’t look as nice when it is set up. You can get by with 3/16″ bolts. There is no forgiveness for sloppy hole spacing.
Lacing looks really neat, and can be unlaced to replace a slat. The downside is that the rope tends to stretch over time, so you will need to retighten them every once in a while. I use 3/16″ woven nylon rope when I do this. There is plenty of forgiveness for sloppy hole spacing. This is my preferred method.
Now you are ready to drill holes in the slats for assembly. Mark the holes using the spacing that you measured earlier. Be as precise as you can be. A drill press makes this job much easier.