I came across an obscure book, The Owner Built Home, By Ken Kern, published by Charles Scribmer's
Sons, New York in 1975. Cheap housing was built in India using a method of coating burlap with cement.
I was looking for a very inexpensive way to build outbuildings. I took 1/2" PVC pipe and made a Quonset
structure with a base of 2'x4' out of 2" wide plywood that was 1/2" thick. The burlap, an old potato sack,
was stretched tight and stapled to the wood frame and up over the PVC pipe to make a little Quonset
building. The burlap was totally wet with water and a thin slurry of Portland cement was painted on and
permeated the fibers of the burlap. Then a thin paste was made of the pure Portland cement and water and
painted on. The result was a beautiful smooth coat that could be painted with a waterproof paint.
The author of the book says to build up the cement, adding sand after the first coat (I used sawdust and it did a great job) to about 2" thick and this will free span a 40' width. After my experiment I don't have any doubt. I am now getting ready to place cattle panels, which are 5'x16' of very heavy wire fence, into the shape of a Quonset and make a storage building using this method. The cost per sq. ft using this material and including the frame is around 60 cents. Building codes say that a concrete slab should support 30 lb. per sq. ft. The author poured a 1/2" thick slab, laid the burlap down and poured another 1/2" and, when dry, tested at 470 lb. per ft. Seems the burlap does the same job as re-bar only much better. By using sawdust that is free in most places, you could build a Quonset or a dome as thick as you like for a song.
Offered by Wayne.
I plan building a dome kit using fiberglass cloth with an epoxy resin. You can get the fiberglass and resin at just about any auto, boat, pool, or hardware store. It doesn't require much space to store, setup is relatively easy, dries quickly, and is very strong and durable when done. With the resin, even burlap would do instead of fiberglass cloth in a pinch.
Offered by Steve.