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Conflict and Natural Disasters
 
Shelter domes for disaster areas
The idea is to build shelter domes fastly and with little gear. The shelter-dome is for inaccessible mountain or remote areas. A central spinning arm and spout climbs on a central spindle while depositing a fluid material that hardens quickly.

Chemists, specialists of natural cements or alike, mechanical designers please empty your brains, it will be for the sake of all disastered families facing winter-time.
Jacob Dhoillander
Responses
 
Shelter domes for disaster areas
Dear Jacob,

It depends upon which disaster prone area you are talking about. Domes are not very good for earthquake resistant structures but for cyclone prone areas they work well. If the domes are intended to be temporary, then you can use bamboo. I am not sure although about its availability in the mountains. Another good option would be adobe domes.
Kanika Agarwal
Shelter domes for disaster areas
Jacob, Foam which hardens upon contact with the air is usually some form of polystrene and is used (a) for lightweight packaging in factories (b) as lightweight insulating material and (c) I believe that today the American police use a much tougher material to spray on violent people who resist arrest. This type of sprayed foam hardens and immobilises the person.

Probably the way to use this spray foam is to build a very lightweight frame structure covered with sacking material and then spray the foam on and finish with another layer of sacking on the outside before the foam hardens.

I believe I saw something similar in one of the "IL" series of books. Note: "IL" is short for the "Institute for Lightweight Structures" at Stuttgart University and was founded by the architect-engineer Frei Otto.

If you are interested in domes, then you should consider my thought about a seven space hexagon "honeycomb" shape.
Frank John Snelling
Shelter domes for disaster areas
Thanks, I was indeed impressed by the domes built from sandbags, maybe it is possible to combine both methods, in a way that a dome formed from small bags is covered with hardening coat on the outside to make it stronger and watertight.
Jacob Dhoillander
Shelter domes for disaster areas
Okay, attention everyone. Does anyone know what chemicals are in the immobilising foam used by american police?

I ask because, this foam must be much stronger than polystyrene and using it to build temporary homes is probably a better use than immobilising people. :)
Frank John Snelling
Shelter domes for disaster areas
Hey Frank, that foam is not styrofoam but polyurethane, the same stuff we use in the roofing and cladding material that we are taking to Pakistan. Polyurethane also comes in cans, a bit like big can of hairspray. It goes off real quick and set hard within minutes.

I can find supplies if people want the stuff. Catch ya later.
David Michael James Davies
Shelter domes for disaster areas
Dave, Thank you for your response. I have heard of polyurethane paints, but there is a polyurethane foam? Wowee.

Questions:- Is polyurethane inflammable?
Does polyurethane give off hazardous fumes when burnt? Does polyurethane foam use environment-unfriendly gases? I am thinking of aerosol CFCs and the pollution-made hole in the Ozone Layer.

I wrote earlier that I thought a quick way to make a temporary shelter was by "sacking on a framework, spray on about 20mm of foam and then cover the foam with an outside layer of sacking".

The bottom line of course is (a) the cost of importing polyurethane cans and both importing and servicing spray equipment; as against (b) the cost of temporary shelters made by other and more conventional means?
Frank John Snelling
Shelter domes for disaster areas
Merry Christmas to all...and hi again to Frank.....to start to answer your queries about the poly foam, I am too tired to write you a long detail account but here is a posting about the stuff, rather long but has further listings included. We are using preapplied foam to the panels we are using, and by the way, we are bringing with us, to Muzafrabad, a couple of accomodation units that we have designed using the standard 760 width of this roofing profile, with 20 mm of insulation already applied and covered with a layer of stipple finished vinyl sheeting, these units, overall dimension of 10 x 4.8 metres, two of them, each with 4 bedrooms measuring 2.3 x 3 metres, and a common room of 4.6 x 3.7 metres, it is will be fitted with a door to each of the 4 bedrooms and one external door to the common room, and no wondows at this stage, we may modify them once we are there, air vents with shutters maybe used, and we will be fitting electric lights and socket to them..meant for storage of personal items of our staff and sleeping quarters, it may be considered a 'Hilton' hotel in temporary housing....it uses only this roofing product for the base..floor, walls and roof...all will be assembled on site and when we leave, we will be relocating the two units to a worthy cause...any way here is 'one' article that will shed more light on polyurethane foam..and no is is not a fire hazard or full of cfc..and the cans are not the most economical way of buying foam, there are simpler methods, read and learn.."Polyurethane foam is no stranger to us," said Monolithic's President David B.South in a recent discussion of home insulation at MDI headquarters in Italy, Texas. "After all, it's a major component of the Monolithic Dome building process," he continued. "But I'm still continually surprised by how little the construction industry and the average American homeowner know about this wonderful product."

South believes that this information gap is, in large part, due to years of clever advertising and promoting by manufacturers of fiberglass insulation. "Many people don't even know that there are other insulating products besides fiberglass -- one of which is polyurethane foam," he said. "But when people understand how insulation works, selling them on the idea of using polyurethane becomes a lot easier."

South explained that heat always travels from warm to cool. For example, in cold weather we heat our homes, but that supplied heat continually struggles to get out of the warm room and into cooler space, such as the unheated attic, the attached garage, or the outdoors. It escapes via any opening, regardless of size -- a window or door, an electrical outlet or plumbing fixture, even a small nail hole. In hot weather, the reverse happens; outdoor heat, using the same escape route, strives to penetrate the cooler interior of our homes.

Ideally, by insulating a structure, we prevent or significantly diminish this heat transfer process. "But here's one problem," South said. "Insulation is rated with a R-value. The R-value is supposed to indicate that material's ability to resist heat flow. Much of the literature, including information published by the DOE (Department of Energy) says, 'The higher the R-value, the greater the insulating effectiveness.' What's usually not explained is that R-values are determined in a laboratory, rather than a real-world environment, and how insulation works -- its effectiveness -- in reality can be very different from how it tests in a lab."

South cited other problems that can mitigate R-value. For instance, a structure usually loses only about 20% of its heat through a conductive, horizontal process. In other words, 20% of the heat escapes by penetrating the outside wall. But that same structure can lose 80 to 90% of its heat through convection, or wind blowing through those walls.

"Then too, heat can be very sneaky," South said. "It can work itself into wood or metal and actually leave a structure by sneaking around the insulation, through studs and joists. Sprayed polyurethane foam or SPF Insulation combats all these heat transfer processes -- usually more effectively than other forms of insulation. It has many big benefits."

Information on various websites maintained by our Department of Energy as well as the SPF industry support South's views, and some list the benefits of SPF:

* Application process creates a seamless, water-proof, durable building envelope

* Eliminates drafts by completely filling seams, crevices and cracks

* Reduces energy use

* Provides high R-values

* Resists water, mildew and fungus

* Adds structural strength

* Provides stability -- does not shrink or settle

* Reduces noise

"We automatically get all those benefits when we build Monolithic Domes," South said. "What most people, even some builders, don't realize is that SPF can be used with conventional, brick-and-stick construction.

"Experience has taught me that 1.8 to 2 pound density of polyurethane foam sprayed to a thickness of 1 1/4 inch will give the home owner 99% of the insulation that we can expect from the walls of a house. Properly applied, the 1 1/4" replaces the structure's exterior sheathing and plywood corner bracing. These items are not to be taken lightly as their installation is costly.

"The best insulated brick house you can buy is one where the brick is laid a half inch away from the wood studs with no sheathing," South said. "You then spray polyurethane two inches thick onto the back side of the brick. The reason that I specify two inches rather than the inch and a quarter is that I want a little more grip on the brick and studs. Polyurethane sprayed in that manner ties the brick to the studs better than any brick ties you can nail to the studs.

"So, the wall literally becomes one piece," South concluded. "The brick -- for the first time, because of the polyurethane -- actually becomes its own total weather service. Now that's a big benefit!"

Note: Author consulted the following websites:
www.monolithic.com/articles/rfairy/index.html;
www.ornl.gov/roofs+walls/insulation;
www.polyurethane.org;
www.lhurethane.com/serresidential.htm.

any way I hope you enjoyed reading that, and can learn more from the other sites listed.. like foam and make use of it in a lot of projects....ciao for now..must get some sleep before Santa comes avisiting........and his little helpers...wish there was a christmas present we could give to the families of Pakistan....perhaps after January we can address that sitiation...bye..dave davies
David Michael James Davies
Shelter domes for disaster areas
Hello,
Impressed by the Ecoshell from MonolyticDomes, but this is a product sold by a company... and not so much a solution for disastered areas. I saw on their bulletinboard a man asking for help to build 5000 of these in Pakistan, obviously supported by the government. Anyone who knows more about this?

So how good is Ecoshell for Pakistan? Is it really necessary to start from an Airform (inflated foil) or can the foam be sprayed over a sandbag structure (no ventilators required) or is there a clever way to spread out foam in concentric way with little more than a centerpole and a (telescopic) side arm..
Jacob. Best wishes for 2006, especially for the volunteers working in Kashmir.
Jacob Dhoillander
Shelter domes for disaster areas
Jacob, I would imagine all you need is formwork (an inner and an outer former) and then simply spray the foam into the space between the formers, so that it expands into shape and then hardens.

In terms of quickly making a dome shape. what about a pair of geodetic-shaped formers (inner and outer slightly curved trangular shapes) to make triangular panels. These could then be spray-fixed to each other.

If you are in a hurry, you could just spray the foam onto a preformed dome shape made of sacking and slap on an outer layer of sacking as you go.

The problem with freehand spraying, is that if the hand wanders then spraying is irregular and uses more material.

If I had the money I would already be there doing the above, but I am tied in a situation where I have no control, so I can only help with useable ideas. :)
Frank John Snelling
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