Cooling a Yurt in the Midwest

[hippiebikerchick]

You have several good points. One mistake I made was going off of floor square footage. I oversized it by 25%, but I didn't take into consideration that it has a high ceiling and poor

insulation

. I used a btu calculator that used both of those variables and it calculated 20k btu instead of 12k. I'm going to temporarily test this by adding another ac unit and if that solves it, I will purchase a mini split. We are also consider another layer of bubble wrap. Even without a space in between the layers, it will increase the R factor by 3.

Originally Posted by thebitmaster

It seems like you're trying most of the right things. Unless there is an air gap between then, adding another layer of radiant barrier bubblewrap probably won't help much. It has almost no insulating value, the only thing it really helps with is reflecting rays that penetrate the cover back out, which is vital. It also, unfortunately, keeps heat generated inside there. One thing you might consider is trying the approach of using comforters on a small portion of the roof, then using an infrared thermometer or leak detector gun to compare the temperatures of that portion and the rest. The guns can be used to pinpoint places where air is escaping.

I can totally empathize with wanting to keep the crown ring looking good. It's definitely the prettiest thing in the yurt. Right now it's a huge pain for me to ventilate because to get from sealed to open I have to wrestle my inner plug out of the way *and* go outside to fold over the roof cover. I have plans for something more like a

dome

with a lift, and a fan in the center, but the need to keep that area looking nice is definitely slowing me down.

Because of this, and the fact that I don't have any screened windows or doorways yet (mosquitos are murder here right now) I've been using the AC at night even though the outside temperature is very comfortable for sleeping. It feels like a betrayal of the entire idea of being more connected to nature and less wasteful of energy. I have a bug screen for the front door coming in today, and I'll be making one for the roof ring also. This should allow me to experiment with leaving the yurt open during the day to prevent heat buildup.

One that that was wasteful but felt really good was running the AC with the roof hole cracked. This felt a lot less stuffy than running the AC with a full seal.

One thing I've never understood about portable AC units. They pull air only from inside the room, but they push air back into the room *and* outside the room. Doesn't that mean that the air pressure in the room should be constantly decreasing? Either that or air is flowing in from somewhere else.

I usually try to escape to Portland, Oregon for the hottest part of the summer, so I don't know if I'll manage to get the radiant barrier installed before I leave. If I do I might do some before-and-after testing and report back.

I think, in general, that it's likely that a cooling solution that doesn't take advantage of the natural airflow out the roof ring may not work. It might be necessary to at least keep the

dome

cracked and run the AC at the same time. It would be very easy to compare both methods and see the result.

This couple put a fan that fits directly inside the roof ring:

Fouch-o-matic Off Grid FAQ page | Esther Emery

I'm planning on doing something similar.

Some people are having success using these with Tiny Houses:

Ductless Mini-Split Air Conditioners | Department of Energy

Another idea I like is a some kind of little tower or cover that floats a few feet above the roof ring to keep out direct sunlight, but still allows in light and airflow from the sides. One idea that Won't Go Away is mirroring the underside so that you can still see nature (and maybe yourself) through the hole.

Scott

[Bob Rowlands]

The real solution to this problem is to erect another yurt one size bigger over the first yurt. You got your sun protection, your air flow, your

insulation

. Plus some yurt forum sponsor is gonna love you, big time. lol

Get a tarp over the yurt so it will not be in direct sun. How? Beats me, but if there's a will, there's a way. It will work, just as putting a hat on your head in the summer works. Think of it as an expensive hat for the brains inside the yurt. lol

I have found a tent fly always keeps the tent cooler in the summer, and warmer in the winter. Everyone heads for shade in the heat of summer.

[Bob Rowlands]

Just brainstorming here. Another possibility if you are home during the day, is to simply wet down the roof. Go out every 30 minutes of so and hose it down. Just like dipping your hat in the lake while fishing, or jumping in the pool while laying out and working on that college tan. lol Nice and cool real quick. Just an idea and they are worth what you paid for them.

[hippiebikerchick]

Bob, I admire your sense of humor! My thoughts are leaning towards building an arbor in the front to shade the windows, I've ordered a 24k btu mini split, and I'm going to add another layer of bubble wrap to the walls and roof. I think I would go completely mad if I had to install a yurt over a yurt!

[Bob Rowlands]

'Goofy' humor. A-Yup!

[Wintergreen282]

A friend of mine (in a normal house with AC, but still is hot sleeping) said she bought a dog cooling pad at Bed, Bath, and Beyond for $40). Put it under her sheet and said it works great. Lol. Not really a solution for this, but perhaps for folks needing a bit more cooling - just to get to sleep until it really cools down at night. I'm going to try it. My theory is it's always cheaper, easier, and more environmentally conscientious (though perhaps viewed suspiciously in our society) to heat or cool yourself as opposed to your space. Esp if you live alone. Experimenting what works best in your situation is part of yurt life. Good luck!!

[hippiebikerchick]

I got my mini split ac unit a couple of weeks ago and it's handling the Arkansas heat perfectly! I ended up purchasing a 24K BTU, which seemed overkill at first, but when I used a BTU calculator and considered poor insulation and high ceilings, this is what was recommended. I'm glad to move on to other challenges. Thanks everyone for your great input.

[Bob Rowlands]

Thanks for the detail.