Mongolian Yurt Style Structures

[BCborn]

Hi folks!

I have just finished a 24' (diameter) Mongolian Yurt, constructed on a deck, built on an acreage in BC Canada. My friend, the landowner, also has one, and has been living in his dwelling for 4 yrs, and has seen winter temperatures down to -30c.

I am interested in discussing these structures with others. In our climate, shelters really need to withstand adverse weather conditions. 80+ mp/h winds and subzero temperatures are not uncommon here. Although many fantastic options are available, price is, and has been, a huge concern for us. I constructed my entire Yurt for less than $800 US.

Breakdown of my setup:

Khanas (wall latices) are comprised of 160 khana sticks, with 5 holes in each

Khanas are bolted together with 5/16 hardware

Rafters (24) are 2x4 construction, 11.6' ft. terminated at a 42" plywood hub, using Hurricane Truss clips, bent, and drilled. Rafter mounted with 1/4" hardware.

Walls were lined with Aluminum Foil Reflectix Bubblewrap and are rated at R 8.3 when used vertically. 6 mil Greenhouse Poly cover the reflectix, followed by used (FREE) decommisioned heavy vinyl Truck Tarps (blue color).

Top was constructed from first Reflectics (R 14.3 horizontal), then a 30x30 (square) polt top, and finally a white weather tarp. This is a cheap method, and we have since switched to using Sileage Tarp, mainly because it is available in 30 ft widths (no tape joints). A 30x100 roll is available for about $160 CDN, and it is 6 mil, black one side, white the other. This is enough material to make three tops, or one top and walls for a Yurt. My landlord went all out and ordered a vinyl 13 guage one piece top, white in color, but it was over $1000. Its main advantage is puncture strength. Give the nature of a Yurt, wind does not affect the structure like ordinary sheds etc., so roof top strength is not a huge issue - more is the method of tying it down. My Yurt top does not leak and we are constantly hammered with rain and recently winds over 100 km/h on occasion. It is however, very noisy inside during these times! I have a window in my top, which offers fantastic ay (and even night) light. If I did again, I would have used clear bubble wrap in the window panel (where the Reflectics is interrupted) instead of poly for better insulation. At the time I thought I wanted the clarity - for more light, but I learned that due to the reflective interior - you dont want "clear" windows of any size, your environment turns more "greenhouse". All of my poly (clear) windows are now covered in white tarps to actually diminish this effect, but still allow light. Clear bubble wrap, (if available in 3' wide) sheets would be ideal, diminished light and insulation.

My Yurt is heated with a small airtight woodstove.

My lighting is mainly achieved by outdoor solar lights, used indoors. They even charge while inside the Yurt, but I often take the out on a rack I made and sit them in the light. On a rainy day they will charge better in my Yurt, under the Skylight than they will outdoors - due to the fact they do not condensate.

Some Pointers:

Do not skip the reflectics. They are essential in any climate both to keep the heat in at night and the heat out during the day. Rememeber reflectics is not insulation - it bounces heat, like a survival blanket. Skipping the reflectics will leave you with a muggy, damp Yurt that may even "rain" inside. An Alternative for Polar climates would be refletics/insulation/reflctics.

My Questions:

My Yurt floor is actually used, free 2x10 planks over the joice work, therefore the ground is under me, no moisture barrier. My skirting is poly to allow light in to control mildew / mold. I have open areas to let air in (but it is VERY important to skirt a Yurt on a deck or the wind will get underneath and inflate your Yurt, believe me its quite the experience, I saw 100 km/h winds inflate my Yurt, and there was nothing actually holding it down! I thought the thing was going to Take OFF! Fortunately it didnt and I got my skirting into place)

Any pointers on further mold control? I am wondering I i shouldnt have removed the forest floor humus (I was rushed and may do that in August when it is nice and dry) I am reluctant to put vapour Barriers under my floor - it will create an environment that connot breathe - right now plants actually live under my Yurt, grow, and stay green. Tree Frogs live under there. This all tells me so far so good - Id ont want to seal and darken the area, I personally beleive moving air and UV are good things.

Anyone want to see pictures?

[bob golding]

yes please, i am in the process of building a 16 foot yurt myself. got all the wood, it is green oak and is seasoning at the moment. i thought of using that foil backed bubble wrap as well. i have a few bits over the windows in my coach,read greenhouse without insulation. for my sleeping area i have 3 sheets of 25 mm  flooring grade "blue board" i think it is called your side of the  pond. high density polyueathane. i am particulary interested in how you did the ring at the top. still thinking about that one. have given up on trying to get canvas at a decent price. its around 4 ukpounds a  sq metre. i can get 100 foot of 3 foot wide foil backed bubble wrap for around 100 uk pounds whick will be plenty for the walls. i dont have to many problems with the cold never gets below about - 5 centigrade. we do get 100 mph winds though, but were i intend to put it there is a sheltering wall and hedge which  should help.

cheers

bob golding uk

[whatsnext]

I'm very curious about something. How long should one last? Five years, twenty? Or is it more like a semi permanent camp? I love one room living so these would be nice if you weren't rebuilding them all the time.

Thanks, John.....

[hvirtane]

Hello,

your story about your Mongolian jurt

is very interesting.

Could you, please post some pictures

here, inside and outside.  

I wanted to ask many questions,

but maybe some pictures would

answer to some of my questions.

- Hannu

[bob golding]

hi john,

 from what have read if you make the  frame out of oak it should last about 60 years. if you use canvas for the cover this will need replacing every 5 years. no figures on  other materials. these figures are for mongolian gers, the correct name for them. think yurt is a russian name for home. they move theirs about 4 times a year so if you dont move much they will last longer.

bob golding

 

[whatsnext]

Bob, So is portability part of the appeal? And, if you were not planning on adopting the nomatic lifestle would you be better off with regular construction. A friend of mine had planned on a geodesic dome but is now looking at copying the RAL system.

John........

[ghurd]

I stayed in one at a state campground.

A couple photos on their site,

http://www.ohiodnr.com/parks/parks/pymatuning.htm

G-

[bob golding]

hi john,

 i think the main appeal is  the design. the mongolians have had around 2000 years to perfect it. although  they  designed it for  thier nomadic lifestyle there is no disadvantage in not  moving it. i have  worked with various domes from  10 feet to 60 foot, and  i dont see any great advantage ,but a lot of problems you dont get with a ger. these are mainly to do with the basic conscruction of the frame. lots of joints to  break or wear out, and thats after you have worked out the angles and made them in the first place.dont get me wrong i like domes but for the work involved i thing a ger is a better bet. smaller footprint as well,thanks to the vertical walls which also means its lowe, which  improves the wind resistance.

bob golding

[BCborn]

Sure -

I will work on that. I used to have a digi-cam but someone stole it from my car - so it may take a little while. You may also like to see: www.yurts.com. Commercial prices for a 24' Yurt, range from $3000 - $12,500 from what I've seen, but that was way out of my budget - in fact, for under $3000 I will have built, plumbed, furnished, and heated my Yurt. As far as I know, many commercial models don't include reflectics, either, for that price! I can't imagine living in a Yurt without reflectics - however I live in the Canadian Rockies - an extreme area to be tenting 24/7 hehe. I will mention however, this is and always be a learning experience. To keep things in perspective our requirements were:

1. Structure had to have enough living space to be comfortable, so 24' (450+ sq ft.) was our minimum size, unless your talking a bedroom addon Yurt.
   
2. Structure should cost less than $1500 to build.
   
3. Structure should withstand highwinds (100 mph +) and cold temperature (-30 c)
   
4. Structure should be portable, and be able to build in about a week.
   
   

My Yurt meets these criteria - although I may end up paying for a few mistakes - we will see. An interesting thing about Yurts is, whenever you step away from the original Mogolian design - there are Pro's and Cons - Always - if only expense.

We have actually built a 16 ft Yurt from scratch for less than $100. It is however, more of shed than anything - but, it has followed the traditional Mongolian Design - using tree branches, and inexpensive canvass. The simpler the Yurt, the more portable - another consideration.

Thats it for now!

[BCborn]

The Hub.

The hub is in an integral part of the Yurt for sure. Our initial design is what I have in my Yurt. It is very simple. In my Yurt, the walls were made from 7' khana sticks, so my wall height is approximately 6'10. This is a bit high for a Yurt, but I'm a tall guy, so it was a compromise. I read somewhere that the wall heaight effects the ability to resist wind, and the lower, the better. While this primarily true, keep in mind even the walls have curvature. Having experienced very high winds I can tell you the walls were my least concern. What is of great concern is that wind does not get under your tarping, roofing, and in my case under your deck. My worst nightmare happened, as I was constructing the Yurt we receive tree-downing 90 mph winds and I didnt have any skirting around the deck! I didnt even have the Yurt "bra" (ropes that hold the top down, and the yurt to the deck itself). I thought the whole sucker was going to lift off and end up in alberta - it was really something to see! The top "mushroomed" there was so much air movement into the structure from winds getting underneath. The walls didnt budge not even an inch.

Nothing was actually holding down the Yurt to the deck, at all! It survived because of two reasons. 1. My reflectics are realitively heavy, and the second layer is poly, the third is white tarping. The wind would have had to rip the reflectics up ward, and literally pull the entire top up, and underneath the only rope I had holding down the top (imagine the roof overlapping the walls 16", with a rope wrapped all the way around the Yurt just below where the rafters meet the top of wall - on the outside). I had the rope just snugged enough that its actually diameter was less than the rooftop edge, and this was a good thing - nearly impossible for the wind to do damage. I have, of course, since added a top "bra, or second ring, which is fastened down, not only holding the top in place, but holds the Yurt to the deck. Another important part is don't make your deck any larger than the diameter - you'll have water running into your yurt.

[BCborn]

somehow the hub data got lost:

It is made circular of 3/4" plywood, 42" in diameter with hurricane clips encircling it. (metal brackets used to secure trusswork to topplates on conventional wood framed walls). They are not for this purpose - but keep in mind, this sctructure is nonconventional, non-conforming. In Canada you need not apply for permits for a Yurt, and I build my whole house for less than 1/3 of the cost of building permits on a woodframe home for my area. The difference is enormous and was essential, for example a normal home might cost $125 per sq ft to build - mine cost less than $2.

[BCborn]

In my case I am looking at a 5 yr plan. The khanas, hub, rafters, and deck will indoubetdly last much longer. Larry's Yurt "top" is made of expensive vinyl used in semi-truck tarping, and is warranteed for 15 yrs. My rooftop is highly experimental, and cheap. It will be beat by next spring. However, it only takes an afternoon to change the top, and its inexpensive. I think, Yurts, unless you are a durable type, are mostly a temporary housing solution:

HOWEVER

if you wanna things further, build a Wood Frame Yurt. I highly recommend these over geodesic domes, they are cheapier and better in wind. It follows a similiar design concept but is usually an octogan shape of wood walls.

[BCborn]

I won't pretend to whitewash my reasons or reason for appeal. My appeal to this house design is that its is DIRT CHEAP, + it's effective. Not too mention it requires no building permits (non-conforming considered portable - no different than setting up a tent in your back yard).

There are lot of "hippy" appeals that apply more to Larry and Vicky my landlords who got me into this. To some they are very real, to others they are silly - to me they are interesting, but not essential. For example - when you live in a conventional home, you are segregating yourself from the earth - what I mean by that is, you are putting concrete slabs and such between you and the earth below. Many, many people, especially native respect Earth's energies. Modern homes, simply do not - they fight the earth and energies and block them. Not being a hippy myself, it really doesnt matter a whole bunch to me - but I will honestly say, I do get a damn get sleep in my Yurt, and have lived in long enough to honestly say there is at least something to it. It is about vibrational energies, both yours a human, and the earths. I'm not going to go into it deeper than that.

The tradeoff is working with shifting levels of humidity and temperature. Keep in mind my Yurt is actually not insulated, yet it functions in -30c! That is pretty bizarre, but it's possible due to radiant heat energy. That isn't to say when I come home the Yurt is stone cold, cause I dont have the heat on. My sun roof panels actually let in heat, the walls bounce it around and it is trapped. It takes about -10 to -15 before my Yurt is below freezing, with NO HEAT. Upon firing my small airtight stove it heats up very fast. Here in the property there folks that have actually snuck over from their conventional 2x6 insulated wood frame cabins, in -30 to sleep in the Yurts, cause they are warmer! That isnt to say we don't burn a lot of wood, but we live in the forest. Much can be done to amplifify a Yurts solar heating capabilites as well. Think of it this way, you stand inside the thing and its basically an inverted solar cook oven. Containing trapped heated via black water barrels filled with antifreeze, is one method I plan on employing so my Yurt is self heating in the winter, while Im NOT there to burn wood. There are many methods. I once saw a guy with a Yurt, and the whole based was skirted in panels, filled with old decommisioned flourescent tubes, painted black in and out, creating a passive heat exchanger! His calculations were that he had 4ft x 35ft of the south side in this system, and on a sunny day his heat exchanges captured over 12,000 BTU hour. He'd get home in the winter and open up a hatch, voila, tons of heat escaping into his living space. He'd then cover the tubes for night time.

[BCborn]

5 years is a very realistic expection. Yurts are not forever - but what $1000 structure is. Your khanas will last much longer, if not moved all the time. Kepp in mind, the heavier you make your khanas - the more stress is placed on making them conform to a circle - and therefore more stress is being placed ont he wood they are made of. Larry used 2x2 sticks for khanas and after 5 yrs they are still in good shape. He has little in the way of UV enetering his Yurt. My khanas are made from 1.5"x5/8" material. Larry after having built his in 2x2 recommended this for several reason. Most importantly, when you cut khanas from B grade lumber its easier to get a nice piece or 5/8"x1.5". This size conforms to a 24" diameter without stress, and is easy to work with. They fold up beautiful, and I could easier put my entire Yurt into a utility trailer and tow it with my car. That is not say I would use this size for camping! It's too much work for that unless you plan on camping in that place for at least a month or two. Make a smaller Yurt for camping! There are issues with larger Yurts that dont occure in smaller Yurts when erecting the structure - for example the rafters. Here in the north, Canadian Rockies we get a lof snow. My Yurt is 24' diameter, my rafter length is 11.6. This produces a Yurt with about a 4-12 pitch. At this pitch the heat loss of the Yurt literally makes the snow slide right off. Mongolians use a much slower pitch but I think theyd get less snow than us. It's not like 3 ft of snow is uncommon here, over night. Larry has a much greater pitch, very steep like a Cape Code Home. (8-12?)

His rafter length is 14'. We both use 2x4 for weight load strength. Larryleft for Thailand one year and returned with 4.5 ft of snow on his yurt - however his roofpitch was such that only at the very top did the snow remain - without any heat in his yurt. Mine, on the other hand will handle perhaps less snow, and require occasional cleaning - if no heat is being created inside. Keep in mind, theres no worry of the snow actually collapsing your Yurt, its the fact that between your rafter the weight will create saggage. If you have a steep pitch, 2x4 rafters or pole rafters, 24 rafters per 24' yurt, and a heavy tarp (13 ga. vinyl) you really have nothing to worry about at all. HOWEVER, as I said before there is ALWAYS a trade off for each design consideration. In this case, Larrys Yurt takes longer to heat, heat is lost to the top. In mine, I can increase the temperature of my Yurt over 30 degrees in under 30 minutes, its almost instant on as soon as I light the fire. My stove is glass faced and I keep it clean - this helps the radient heat echange, or at least i think it might - it seems to.

So in summary - think of your yurt as a 3, 5, or 15 year building, depending on your choices in materials, budget.

Having said that, the guy we learned this from has been living in his Yurt for 12 years now and its a cheapie. He throws and afternoon or three of his time and a few hundred bucks at it, per year and has never changed his khanas or rafters, or hub. Only his wall and roof coverings have been replaced and he started with used materials to begin with! (As did I)

[BCborn]

If you have gone to the trouble of buying oak for khanas (possibly for strength and visual appeal?) i would say go with a conventional rafter POLE (not 2x4) and make either a circular solid frame hub with angled entry holes, or a multisided 4x6 octogan with 3 poles per side. Imagine a wooden donut with 24 holes all around the ring, or an octoganal 4x6 ring. Use only glue and dowels, and avoid nails and screws completely. This can be done best by lamination of wood then drilling it. This is closest to the original Mongolian Ger/Yurt. It is a very strong dsign and beautiful too! Our design is a really a quick and dirt, however due to the nature of the hurricane clips allowing the rafters to pivot, it actually works very well in wind. It looks crappy though. Keep in mingd my Yurt was CHEAP CHEAP, I'm not a wealthy guy, i live VERY meager compared to most.