for the footer i would suggest using ground contact treated 2x4's secured to the ground with stakes. Rebar should work for several years.
Basically a ring around the bottom of the footprint of the Hexayurt. You could use the builder adhesive. I've made stress skin panel out of it for years. Has you considered that? You could also make a stress skin panel out of sheet steel, and use your window flashing and adhesive as the bridge over the gap. This would be lighter, i think, than the clay/concrete? i also think a metal exterior would shed snow rather well and you could get it in all kinds of pretty colors. I think having the inside covered with something fireproof is essential to long term habitability, otherwise it can be a significant fire hazard. I've done 3/8 inch sheet rock / 2 inch foam / 3/8 inch plywood exterior in other structures to good use. You can use the flashing, with the "l" or "t" side between the panels, and that will also add considerable rigidity and strength. Another consideration is the expansion and contraction of the clay/concrete overcoat. I do not have the co-efficient of expansion and contraction difference. however since that can become a problem in conventional foundation construction, You may end up with a flaking off of the clay/concrete over time. Particularly with a monolithic coating. If you use SIS panel, the "spacer" of the adhesive and flashing could help to allow for expansion and contraction. I know that the foam is designed to have a similar expansion / contraction relationship with plywood. Here is more than you ever wanted to know about plywood : http://home.howstuffworks.com/plywood.htm Some projects require that you use or at least understand plywood. This material is a very popular construction tool, because the layering of thin sheets of wood gives it great flexibility and strength. Knowing about plywood can save you money and may mean the difference between a successful project and one that fails. For example, you don't need to buy an expensive piece of plywood that's perfect on both sides if only one side will be seen. Similarly, there's no sense in paying for 1/2-inch thickness when 3/8-inch plywood is really all you need. Plywood also comes with different glues, veneers, and degrees of finish. By knowing these characteristics you may be able to save money as well as do a better job. [image: Plywood] *Plywood is a commonly used material because it resists shrinking and cracking.* Available at home centers, hardware stores, and lumberyards, plywood is better than lumber for some jobs. It is strong, lightweight, and rigid. Its high-impact resistance means plywood doesn't split, chip, crack all the way through, or crumble; the cross-laminate construction restricts expansion and contraction within the individual plies. Moreover, you never get "green" wood with plywood. When you buy a sheet of plywood, you know exactly what size you're getting, unlike with other types of lumber that have nominal and actual measurements. For example, a 4 X 8-foot sheet of 1/2-inch plywood measures exactly 4 by 8 feet and is exactly 1/2-inch thick. Plywood is broadly categorized into two types: exterior and interior. Exterior plywood is made with nothing but waterproof glue and should always be used for any exposed application. Interior plywood, made with highly resistant glues, can actually withstand quite a bit of moisture. There is interior plywood made with IMG (intermediate glue), which is resistant to bacteria, mold, and moisture, but no interior plywood is made for use outdoors. When purchasing plywood, look for a back stamp or edge marking bearing the initials APA or DFPA. APA stands for American Plywood Association, while DFPA is the Douglas Fir Plywood Association. These two organizations represent most of the plywood manufacturers, and they inspect and test all plywood to ensure quality is high and grading is accurate. The most critical plywood grading category for most home projects is the appearance grade of the panel faces (see the chart on plywood grades below). PLYWOOD GRADES Interior Grade Face BackInner PliesCommon Uses A-A A A DCabinet doors, built-ins, and furniture where both sides show.A-B A B DAlternate for A-A. Face is finish grade; back is solid and smooth.A-D A D DFinish grade face for paneling, built-ins, and backing.B-D B D DUtility grade. One paintable side. Used for backing, cabinet sides, etc.C-D C D DSheathing and structural uses such as temporary enclosures, subfloor. Unsanded. Underlayment C-plugged D C,DFor underlayment or combination subfloor-underlayment under tile and carpeting.Exterior Grade Face BackInner PliesCommon UsesA-A A A COutdoors, where appearance of both sides is important.A-B A B CAlternate for A-A, where appearance of one side is less important. Face is finish grade. A-C A C CSoffits, fences, base for coatings. B-C B C CFor utility uses such as farm buildings, some kinds of fences, base for coatings. C-C plugged C-plugged C CExcellent base for tile, backing for wallcoverings, high-performance coatings. C-C C C CUnsanded, for backing and rough construction exposed to weather. Here is a link to the Owens Corning Product page, The 250 Formula of the pink foam is superior than the "150" formula used in wall installations. The 250 is designed for direct contact with soil / concrete / etc. and is more rigid than the 150 formula which. http://secure.owenscorning.net/Portal/uploads/document/20051110/43522-E.pdf -- You received this message because you are subscribed to the Google Groups "hexayurt" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/hexayurt?hl=en.
