Geodesic Dome

[Rob Tucker]

Jyoti,

I have built domes that size. It is wise to have few, if any, interior walls touch the exterior shell. You will not find any contractors here with experience on the subject. I would suggest you buy a kit for the shell and that the kit price should include engineering calcs stamped (preferably) by an Hawaii licensed engineer. Most out of state engineers can pick up a Hawaii license for a couple hundred dollars.... you would likely have to pay that.

While geodesic domes have a reputation for covering the most space with the least material they are very inefficient in material use. They are made of triangles and all sheathing material is produced in rectangles. So the frequency of the dome needs to be calculated in a way to minimize waste if a sheathed frame is chosen. Done wrong there will be a lot of waste. Waste is money thrown away.

The best designs I have seen are made of foam panels with a monolithic spray on water-proof membrane. The only company I know of doing this is in Virginia (though there may be others).... a lot of shipping. http://www.commonwealthsolar.com/cwdome.htm Containers are costly. Foam panels are light and bulky. Wood frame designs are a bad bet in this climate. Every joint in a wood frame design is a potential point of leakage. Domes are also complicated to gain water for catchment.

A 40' dome can be a challenge. A series of smaller connected domes is worth considering. White is a difficult color to maintain here.

Lastly, you should be aware that the resale value is tough. Your resale is a niche market... hard to find buyers.

Good luck.

[unknownjulie]

This look very interesting Rob.

[Rob Tucker]

Hmmm. I think you are over stating cinder's structural characteristics. It would be nice if it were true. There is lots and lots of cinder here... but cinder was eliminated from "cinder block" because of it's poor properties.

[Seeb]

The cinder in blocks was never the volcanic kind, it was fly ash and clinker

[csgray]

If you want a monolithic type dome using local materials there have been a few earthbag homes built here using cinders. Super simple construction requiring few specialized skills until you get to plumbing and wiring, but I would want more windows and bigger doors.

http://www.earthbagbuilding.com/index.htm

Carol

[Jyoti]

thanks Rob for your thoughts and experience.

I'm still at square 1 with some preference still towards domes.

Your recommendation of 'include engineering calcs stamped (preferably) by a Hawaiian licensed engineer' looks very helpful, thanks.

I can wait for the 'niche' resale, thats a good point, though.

I checked the link and went through it, I like it! [] I didn't see any kit details there, so I sent an email.

Yeah, materials, wood is the worst but contractors are familiar with it, so they use it.

How about a cement composite dome or adobe ?

[Rob Tucker]

"How about a cement composite dome or adobe ?"

Adobe makes no sense here at all. A composite cement dome is doable but you will need an engineer to handle the design. Sleeping under tons of weight needs to be done right. There is a man here that sprays gunite. He would know more. I think the name is Pacific Gunite. They do good work.

The best dome I have ever seen was in the Blue Ridge Mountains of Virginia. Completely illegal there and here but it was well built, functioned beautifully and was, in my opinion, quite safe. The builders had a rural parcel and built a hub system wood frame. Over that they placed clear plastic and then proceeded to spray, inside and out, several inches of polyurethane foam. They left some areas of plastic unfoamed for windows/light. The thing was cheap to build and was toasty warm on a winter day without heat. You could walk on top of it without concern. The inside was a series of tiered patios with slate floors and walkways mixed with small gardens, kitchen, bath, seating and sleeping areas. It was a bit unusual to hear the dogs chase each other over the dome with the pounding of dog feet. I was impressed. Totally watertight.

The downside of this is it was not legal, unpermitted. It was not likely to be legal either due to the toxic smoke issues from the polyurethane foam in event of a fire. But otherwise I gave it an A. The owners had a foam insulation company and the equipment was at hand as well as the foam source.

Of all the domes I have seen or built this was the one I could live in.

[Jyoti]

I did a google search and found an interesting dome company out of Florida (what is is with these southerners?)
The company name is American Ingenuity Inc, they had VERY detailed information on the whole process from materials to shipping.

I've seen the monolithic dome 'Spray' on the net, done with a huge inflated ballon.

Out of all modern building materials I prefer concrete composite as it is sturdy, looks like stone, and blocks some of the waves (cell, micro) out there like a cave does.

[Peter Epperson]

http://pacificgunite.com/ferrocement.htm

[Rob Tucker]

You should talk to Peter. He knows his stuff.