Moisture in the Yurt from Condensation

[Bob Rowlands]

You know in all the Mongolian yurts I've seen in photos and videos I don't recall ever seeing a

dome

or cap. Their smoke holes/rings are covered with a large cloth flap with four attached ropes that drape down so the flap can be pulled over the smoke hole and snugged around the pipe. I don"t believe they have air tight stoves so the stove pipe carries out interior air, let alone the gap that must be left around the single wall pipe if the stove is being used. I'll make guess here and say the air comes in around the door and exits the smoke hole and stove pipe all the time. That absolutely happens in my yurt. Plus it isn't insulated so it doesn't hold the heat at all.

[Kiwassa]

I've got layers of

insulation

throughout my yurt. The outer layer is a 10 mil plastic sheeting. What I've noticed is that condensation collects on that outer layer.

This year, my solution was to put another layer of the same sheeting inside as the inner most layer with blankets between them. Essentially you're creating an airspace between the two plastic sheets which makes the surface of the walls much warmer. As a result, I'm not having

moisture

collect on that outside wall as I was last year.

I have to believe the

moisture

is expelling itself through the

dome

, or the stove pipe. The issues with condensation were pretty extreme last year...so far so good this year though.

[Jafo]

Kiwassa, that sounds great. I am thinking you are also creating a better heat/moisture barrier for the roof. Less moisture and heat are making it there, leading to less condensation. Great job. Keep us posted how this continues please!

[Bob Rowlands]

Thanks for the post kiwasa.

[TKOAK]

We live in Big Lake Alaska and it was -13F last week. Last (2014) Thanksgiving is was -29F. We do not have a condensation problem. I have been reading and wondering why. It just dawned on me, that our yurt has Sunbrella fabric as the outside walls. We have a 18 oz vinyl roof. Pella windows and a 4 ft acrylic dome. We heat with wood and oil toyo stove. Standard house door. NO Condensation.
I think the sunbrella Marine fabric breathes. Our

insulation

is 1/4 inch this solar Guard by BP Solar. The roof has a 1 inch polyester blanket over the Solar guard. (reinforced vinyl, 1/4 inch fiberglas, and layer of pure aluminum)

We have had a problem with the Honda eu300is freezing. I made a blanket of Solar Guard and it now keeps itself warm.

[Groovyyurts]

Originally Posted by Bob Rowlands

I've noticed Mongolian yurts have walls lower than those here in the U.S. Less height, less volume=easier to heat. I understand it is dry in Mongolia, however just possibly the warmer it is inside the less likely condensation can be an issue. Just a guess
... You know in all the Mongolian yurts I've seen in photos and videos I don't recall ever seeing a dome or cap. Their smoke holes/rings are covered with a large cloth flap with four attached ropes that drape down so the flap can be pulled over the smoke hole and snugged around the pipe. I don"t believe they have air tight stoves so the stove pipe carries out interior air, let alone the gap that must be left around the single wall pipe if the stove is being used. I'll make guess here and say the air comes in around the door and exits the smoke hole and stove pipe all the time.

you're right! The more compact shape of the Mongolian ger / yurt means also less surface in contact with the exterior = less surface for condensation and ... less moist air to deal with...
And yes, there's always a bit of air escaping from the toono in Mongolia and the stoves (in which they burn mostly dried animal manure) are far from air tight. Those of our customers who seem the most successful at dealing with moisture... are the ones using their gers just like that :-).
It is also important to underline that traditional yurts in Mongolia are usually between 5 and 6 m diameter (16 to 20') and this is how they are so efficient in their extreme climate.

[Swykes]

We live in Northwestern Ontario and have recently moved into a 32’ yurt. We are battling the condensation issue inside. Moisture collects on the inside of the dome, then rains down on us. We heat with propane, so when it gets cold, it’s too expensive to open the dome and let the heat out. We have real windows, but even leaving a couple of them open a bit, doesn’t seem to help. We have put a fan near the peak, have run a de-humidifier and have tried putting bubble wrap up there as insulation. Nothing worked. It continued to “rain” inside the yurt. We don’t plan to live in the yurt most of the winter, but would like to if need be. I was wondering if you think a custom, 2 or 3 pane plexiglass window might help? It would be constructed so that it would be removable, and fit over the dome opening inside the yurt. You said that 2” styrofoam worked, but you lost the light. Would a double or triple pane “window “ insulate as well as the 2” styrofoam? The humidity in the yurt is not very high. I have even put a humidistat up inside the dome, and it isn’t overly high. The windows never have condensation, only the dome, which then rains down onto the furniture, the floor and anyone sitting on the furniture. When you used the styrofoam, was there frost buildup on the dome side of it? Did you leave the dome open a bit once the styrofoam was installed? Are you and your family still living in the yurt? Thanks!

[hagfish]

Originally Posted by Swykes

We live in Northwestern Ontario and have recently moved into a 32’ yurt. We are battling the condensation issue inside. Moisture collects on the inside of the dome, then rains down on us. We heat with propane<snip>

Burning a 'gallon' of propane produces four gallons of water, so if your propane heater is free-standing, all this will be contributing to your indoor-rainfall problem. Hopefully fluing the exhaust gasses outdoors would make a big difference.

[Bob Rowlands]

I have trimmed a few stick framed houses in the winter over the last few decades that were temporarily being heated with portable propane heaters because the permanent heater wasn't fired up yet. The type I refer to is simple- a large propane tank that has a burner attached to it with a valve and hose. That type heater throttled up to jet engine blast heats a large freezing cold area fast. A 32' yurt at freezing would be toasty warm in just a few minutes.

However, while the heat output is phenomenal, breathing propane combustion gas all day is NOT good, and the moisture produced is incredible. It flat out sucks breathing that air all day. NO WAY I would use that in a permanent residence in fact it would be illegal. A very drafty smaller uninsulated primitive yurt or wall tent with lots of air loss, yes. Just let the unit idle like we do at work and it is not all that bad. Beats freezing your keester.

You definitely need another heater for your yurt. Tight yurts are said to have all kinds of condensation problems, and dumping propane combustion into them would be a fail imo. Dry heat from a good wood stove is good. A regular propane fired forced air furnace that dumps combustion gas outside, would also work. There's a heat exchanger inside so only warm dry air enters the yurt.

fwiw you might find a used one in good condition on Craigslist. Some guys install those in their garages. Good luck.

[Bob Rowlands]

I just remembered, back in the 1970s I used to live in a 20x20 1 bed 1 bath apt. SMALL! It was two areas divided by one wall, each 10x20. A lr/kitchen and 1 bed/bath. Not unlike a 24' partitioned yurt. The heater was a single wall mount furnace in the lr. That worked OK through the winter. The bedroom stayed pretty cold even with the door open, but it was good enough for me. Nowadays I would want another heater on the wall in the bedroom side. So, a wall mount furnace is also a possibility. No ductwork necessary.