Green roof on a yurt?

[alirobs]

Hello yurt community! I am new to this forum and think it's great that everyone can help each other out on this site with there yurt building adventures! My boyfriend and I are going to start building our yurt in the next two months and are currently planning away, we are building are whole yurt from scratch!

We've looked at ordering a custom yurt cover from various companies as well as making our own, but we are stuck on the idea of having a green roof on our yurt!!

We saw a youtube video of a project house that was built with a fabric material as the roof and then sod was laid overtop as a green roof (great insulator!) and we thought we could do the same with our yurt!

Just wondering if anyone has any experience or knowledge about this idea since I cant find any examples of a green roof on a traditional yurt, only solid wall structured yurts. I know that a sod roof is heavy so I THINK it will be able to handle it but I'm not positive how strong a traditional Mongolian yurt roof really is, as we also live in Canada and will have snow over the winter. We are putting the "baghana" (roof wheel supports) in as well.

Our plan is to have a layer of canvas, then a waterproof layer, than a drainage fabric layer and then the sod. PLEASE help if you can as we really want to do this but am worried to take the risk of the load of the roof without more info on it.

THANKS GUYS!!

[alirobs]

We are also using round poles for our lattice instead of thin slats! Which from what I've read adds a lot of strength to the wall structure

[hierony]

Interesting idea. Personally I wouldn't put a green roof on a yurt, though I have been tempted to make an underground yurt. I'm guessing this will be a semi-permanent yurt--maybe make straw bale walls with yurt roof?

Wet dirt gets heavy, especially if you accumulate snow on top and get rain (ie, springtime). Yeah, the lattice is what I'd be worried about--I'm not sure it would be appropriate in this instance. The roof poles would probably need to be pretty sturdy of course, and maybe have a lot more of them than normal. Special attention to your junctions/connections will be important--don't want to overload any of the materials & get junction failure.

[alirobs]

Ya I actually started looking into the hay bail walls last night! Not sure if we want to go that route as it will be our home for the next little while, but then plan on moving it to our own property in a few years.

The traditional Mongolian yurt design has almost double the roof poles as the more modern North American styles, so that should add to its strength, plus the 2 load supports under the roof wheel.

Am wondering if I also model my frame after some of the Pacific Yurt designs that have a support beam underneath each roof pole if this would be substantial.

I feel like it could handle it with all of that extra support but again I've never owned or built a full sized yurt before! Do you think it would be strong enough with all of that extra support built in? If not we will probably just stick with a traditional yurt cover, we're willing to take some risks but dont want to risk our home caving in!

[alirobs]

Maybe attaching the roof poles to the roof wheel and support beams with metal brackets would also help?

[Bob Rowlands]

If the sod roof yurt needs to go through a Canadian regional building dept., all I can say is good luck.

[Bob Rowlands]

Three feet of wet snow yields a load of about 15 pounds per square foot. Wet sod might weigh the same er square foot. Maaybe kmore. So, for fun, 30 pounds per square foot times a 450 square foot roof, that is 6.75 tons of weight on the walls and bagana. If you had a 24' diameter yurt, you'd have 75 feet of wall, including the door. If the wall carries half the total load, that is 90 pounds of weight per lineal foot of wall. That also assumes the bagana carries half the roof load. With three bagana that is a vetical load of a ton plus per post. I have no idea at all how the tension band carries the load or how to figure 'yurt roof load calcs'.

I'm no engineer but, there are some numbers to kick around. Yurt wall footage is yurt diameter times 3.14. Sq footage of yurt is r2 x 3.14. Have fun!

[alirobs]

We actually started looking into earthbag walls covered in plaster as they're extremely strong, also thinking about the underground idea as well.

Thank you guys!

[Bob Rowlands]

That's a better idea. Or, just build a small rancher? Easy to get through regional and codes, cheap because every trade is in and out super fast, and yup they are built like a tank. It's 'the' home for tens of millions of Americans and Canadians for many good reasons. A small rancher over a basement is absolutely a superb house. Nobody is gonna reinvent that wheel and improve it.