Hi All,
I don't have a cost comparison, but for insulation and ease of construction I think SIPs have some real advantages, particularly if you may want to move your yurt in the future.
If you can get a quote from the SIPs factory, (I have been trying to get a cost estimate since the middle of December from a SIP factory in Kellog, ID), be sure to ask about the distance they can span. I think even the 4" SIPs will span at least 6' (maybe even 8') and stay within the amount of floor deflection allowed by code, but it may depend upon the manufacturer.
This could work out to a lot less digging, setting posts and dealing with the heavy (and expensive) dimensional stock under the yurt, and you should end up with a floor that could be more easily disassembled and moved, and still have the possibility of meeting code and standards for deflection. It also can give you channels to install power (as an example) in the floor.
Theoretically the factory can also shave the foam and the top surface of the SIP to allow a "lip" of 3/8" (most flexible) or 1/2" plywood to be more easily added around the perimeter of the floor to help with the sealing of both the foam insulation inside the SIP, and the yurt fabric overlap.
I think it is a great idea, but I have not been able to find an answer to the question, is it cost effective?
I am anxious to hear what the factory has to tell you about it.
Another answer I see locally is a round floor poured in concrete.
It might not be the best answer everywhere, and it certainly isn't very mobile, but if you intended to have a permanent location, you might consider it.
If you are planning to use wood heat you could install insulation under the concrete and around the edges, and running plastic piping inside the concrete. In this way I think you could easily have a floor that was warm in the winter, using the excess heat from the woodstove, and investing it into your concrete heatsink/floor in a simple non-pressurized system.
A 12 Volt fountain pump would probably be enough to make the water, and thus the heat, more effectively move through the floor.
Be aware it would make it harder to be away from the yurt in the winter without first draining your floor, so think carefully before making this installation, and/or prepare a drain system before you install the concrete. Actually, make the installation, just plan carefully before you fill it with water. The pipes in the concrete would not be a problem as long as they were dry, and they would be really difficult to retrofit.
A couple thoughts for you, and there are a couple more on my website if you dig around, like using a groundcrete floor, depending on if building codes may be in an issue.
Rod
rod
yurtlocker.com
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