Steam Heat

Karyn Borg

Hi! My name is Karyn and I live at Swanton Pacific Ranch(www.spranch.org) in Davenport, CA. This ranch is owned by California Polytechnic State University, San Luis Obispo. This is a student assisted run ranch.

I need help. Alot.

1st the specifics
Currently I am researching ways to safely and effectively heat a Yurt. A Yurt is technically classified as a tent-it is a circular structure that consists of a durable fabric cover, tension band & a wood frame that includes a lattice a lattice wall, radial rafters, central compression ring and a frame door.
We have students that come up on the weekends to stay in the yurts. Therefore we need a Safe way to heat the Yurts that is also cost effective, and inexpensive(this is a non-profit organization-not alot of dough comin in).

Any suggestions???? Feel free to e-mail me.

Thanks,
Karyn

Constantin

Hmmmm....

Given that these are temporary structures and only in use 1/5th of the time, I would consider putting strawbales below the Yurts to limit heat loss down to the ground. With adequate drainage, they ought to last a season.

If the heat loss is low enough, consider running 1/2" PEX lines on 9" centers in a spiral pattern under the frame to heat the Yurt. With any luck, your existing heating system is water-based, which would allow a inexpensive and safe tie-in via some underground, insulated PEX lines. This could work well unless there are freezing conditions in which case you might need glycol or similar means to keep the system fluid.

Steam heat is another option and it's pretty freeze-proof, but installing one from scratch is pretty uncommon in residential applications. If you have a pre-existing steam plant, by all means consider it.

Brad White_30

Or pull another

Yak into the yurt with you

Sorry- just getting in touch with my Inner, not Outer, Mongolian.

In a playful mood today.

Brad

Karyn Borg

response's to steam heat-Thank you, but more please.

Constantin-hello.

Thank you many times for your help. I have a few Q's and additions to your suggestions.

The Livestock manager said hm and appreciated the suggestion about the strawbales.


The heat loss is serious(the ranch is approx. 1 mile from the ocean). The Yurts reside in different locations on the ranch-one is located on a high mesa over looking the sea level. The two others in the forest same sea level but trees surounding. What is a PEX.???

There is no existing heating system. This ranch runs on propane-this is CA.

Brad White_30

Karyn

I think the best way to start is to calculate a heat loss. If these are like the Yurts I have seen, there were several layers of wool "blankets" (in fact they were blankets and raw wool) wrapped over and around the expandable frame. Fairly cozy.

If we can get an idea of the area and materials in each component we can get a start. Key factor is air leakage, infiltration, especially in your locale. The straw bales Constantin mentioned will go a long way. What is the coldest it gets there in your estimation? I can look up weather data for near St.L.O. as well. But you get an idea what is needed.

Question: Are these true Yurts being temporary nomadic structures or are they being adapted so something more permanent? The fact that you want to heat them indicates a desire to depart from authenticity and explore different materials, means and methods. So if they are permanent, a true system can be designed. If temporary, there will be a wider degree of deviation from expected results.

Constantin is spot-on regarding floor radiant. Radiant can compensate for drafts to an extent by heating people and objects, not air. Think of how much warmer you are in the sun than shade when it is windy and or chilly.

PEX is cross-linked polyethylene plastic tubing, popular for radiant floor work. Warm water (between 90 and 130 degrees more or less) is pumped through the tubing to heat the floor surface which in turn heats you and objects.

Your challenge here is to have insulation below it. You have to "drive the heat upward" or else you will drive more than half of it down into the earth. A sample installation might look like this in layers:

-Flat earth, graded and well-drained

-vapor barrier, maybe 6-mil poly sheeting

-insulation: high compression strength extruded polystyrene. At least 1.5 to 2 inches thick

-Network of PEX tubing spaced to suit heating load and pattern of exposed floor area. Held down with what, I do not know. Can be laid between plywood strips if equal thickness to the PEX tubing (1/2 inch is a representative diameter, varies 3/8" to an inch or more).

Coverage of this floor might be earth, well-tamped if temporary but if permanent, concrete is hard to beat for heat transfer.

Key to this kind of installation is that what goes on top of the tubing has to be limited in insulation value (makes sense) while slowing the downward flow of heat.

The above general description would work better if these Yurts had a stable foundation (yes, permanent) with an insulated perimeter too. If these had foundations and an appropriate heated slab, it may allow the upper structure to still retain authentic construction techniques.

The sysetm overall could be driven by a propane-fired hot water boiler. Depending on the proximity of the Yurts (clustered or remote) you could have a dedicated boiler to each or a central structure enclosing several to heat all. Lots of variables, lots of options.

I do want to stress that the boilers have to think that they are indoors, so in a permanent shed of some sort. I suppose a portable shed could be designed with all included (that would be fun to design!) but the key is that the combustion products be clearly away from the occupants with no chance of settling within the sleeping areas.

But radiant, IMHO, is the way to go.

Brad

Constantin

Some thoughts...

I'll tag all of Brads suggestions as excellent because not only do I agree with them, but I'm just a homeowner and he's a certified designer. His suggestion about concrete slabs with insulation below is a great one if the intent is to have "permanent" yurt platforms.

If the students are not roughing it, (i.e. have a shed with a composting toilet, running water, etc.) then that structure is a prime candidate for a heating source that runs on propane.

Once you know how much heat these Yurts need to stay warm, you can go about casting for a heat source. PEX is a type of plastic tubing that is frequently used in radiant floor heating applications.