Alternative Hexayurt materials

[CCPants]

My first year I baked in an uninsulated nylon tent - not looking to do that again!

I found many great resources for building a Hexayurt on http://www.hexayurt.com and http://www.appropedia.org/Hexayurt but there's one question I haven't found an answer for yet:

Is there any reason not to build the hexayurt out of plain structured insulation panels (the blue or pink boards at every hardware store) rather than the aluminum-skinned versions?

I'm imagining there might be MOOP issue or something... but they seem so dense! And as for insulation, the R-factor of the blue/pink boards is about double that of the aluminum-skinned yellow material. Is it a question of radiated vs. convected heat?

Any help would be greatly appreciated!

[jkisha]

I don't really know the answer to that but I'd venture a few guesses.

The first one is definitely a possible moop issue. The next guess might be water...i.e. what are the specifications of the panels? do they stand up to water? My next guess might be stability; as thin as the aluminum is, I think it might help with that. What about the cooling effect from the reflective quality of the aluminum?

Hexycomb cardboard was also suggested as an alternative on the hexayurt site, if I recall.

If you think the material is suitable, why not try it and report back?

[JStep]

I think I seem to remember someone mentioning that the foam insulation crumbles. If you're going to use it, I would think it best to at least cut it and tape all the edges at home and not try to cut the foam on the playa where little foamy bits will fly everywhere.

ETA:
Ah, I just remembered... for Burning Man specifically it was recommended not to use foam insulation as it's brittle and someone who happens to stumble and fall into your yurt wall will probably break the panel, rendering your yurt useless for keeping cool and sheltered, as well as the aforementioned moopy foam bits.

[CCPants]

The first one is definitely a possible moop issue.

Yeah, that's what I'm thinking. The dust and any other material might pull off some of the foam, which would be unfortunate. The foil skin on the standard panel should provide some protection.

The next guess might be water...i.e. what are the specifications of the panels? do they stand up to water? My next guess might be stability; as thin as the aluminum is, I think it might help with that.

I believe the blue/pink panels are waterproof, and the foil skin isn't structural unless you're buying Thermax HD.

What about the cooling effect from the reflective quality of the aluminum?

That's exactly my question - is there a reflective benefit to the foil skin which equals the improved R-value of the pink and blue stuff? Probably is, as the instructions I mentioned above all advise putting the logos inside, and the shiny foil outside.

Hexycomb cardboard was also suggested as an alternative on the hexayurt site, if I recall.
If you think the material is suitable, why not try it and report back?

I think I'll go the safe route this time, unless I hear otherwise about the pink/blue cohesion issue.

thanks for the thoughts!

[CCPants]

I think I seem to remember someone mentioning that the foam insulation crumbles. If you're going to use it, I would think it best to at least cut it and tape all the edges at home and not try to cut the foam on the playa where little foamy bits will fly everywhere.

Agreed - all the BM sites say not to cut on the playa (and really, why would I want to do all the construction out in the desert heat?), and to tape the edges (preventing foam MOOP).

Ah, I just remembered... for Burning Man specifically it was recommended not to use foam insulation as it's brittle and someone who happens to stumble and fall into your yurt wall will probably break the panel, rendering your yurt useless for keeping cool and sheltered, as well as the aforementioned moopy foam bits.

Hmm... the foil covered panels aren't much stronger, as I recall - except for the Thermax HD which I don't want to deal with (sourcing, cutting, hauling the extra weight...) If you have a source for that recommendation, I'd love to get the link - it sounds like a page I haven't visited yet.

Much appreciated!

[gyre]

You need to look at uv sensitivity with exposed panel materials.

Structural foam varies considerably in density and strength up to the toughness of solid wood.

I have used structural polystyrene to pad a car in transit, and it is much tougher than it looks.
I left it exposed to wet and sun for many years, which it isn't designed for, and it took a very long time to fail.

There are polyurethanes with heavy laminates on the outsides for protection and panels made for refrigeration with steel covers that link together.
I have seen trailers built of these.

I can't speak to the pink and blue you refer to.
I'm not sure what they are.

Aren't most foams supposed to be cut with a hot knife to seal the edges?
Or sealed after cutting?