Under the Silver Arches

Some of the most promising housing concepts have run into dead-ends for the strangest reasons. Such was the case with one of the simplest and most commonly used form of industrial building in the US.

One of the most recognizable architectural icons of the WWII era is the corrugated steel arch quonset hut. A fixture of both innumerable military bases and airfields during the war, post-war this simple structure became almost ubiquitous among American farms and rural industries. The quonset hut is the epitome of industrial architecture; a clear-span structure of potentially very wide span assembled from simple prefabricated parts made of resilient industrial material. When humans finally colonize the Moon and the other planets of the solar system, some form of this structure will be used there. Since quonset hut structures are typically composed of a metal arch shell atop a concrete slab foundation, the potential application for non-toxic housing is obvious. And the use of these for housing is not all that unusual, having begun with the recycling of surplus military structures and then extending to new building built using arch systems made for the agricultural market. But the arch geometry has its limitations and the various arch products some rather peculiar complications.

I was first introduced to the use of these for housing through two unusual sources; a unique underground home built in the US of steel culvert arches in the 1970s and an equally unique apse-shaped earth-bermed home built by an avant garde designer in Japan. Both these structures shared a similar adaptation strategy; concrete slab floors with hydronic heating, the finishing of the interior cheifly by the application of spray insulation foam, and the enclosure of the ends by glass walls compensating for the inability of the steel shell to readily accommodate side windows.

As long as one used a non-toxic insulating foam like isocyanaurate polyurethane foam or Airkrete mineral foam, such structures should be quite non-toxic and perform very comfortably and economically as a home in most any environment. Thus I explored the simple strategy of a single free-standing or earth covered arch structure supporting an open-plan home design. The chief design complication, however, is the arch shape whose edges create volumes of space that are not easy to use and do not accommodate the placement of conventional furniture -a problem which also plagues the use of dome buildings. I observed that when these arches were adapted into homes by DIY builders it was very common for them to employ extremely elaborate but ultimately crude carpentry to try and frame-up partition walls in order to divide the unusual shaped space into individual rooms or force-fit conventional furnishings. This complication was related to the arch size, the home owners trying to make the most of the smallest arch size and then unexpectedly running into this problem with the arch-edge space. Some arch building manufacturers have addressed this problem by creating pitched roof forms but these generally don't work as well as the traditional arch because they support much smaller spans and roof loads, eliminating the potential for earth covered structures and also increasing cost.

The professional architects who designed those structures mentioned earlier addressed the problem in other ways. In the one case, the architect created a branching network of buried culvert arches which were sized such that each branch accommodated a single room space which was furnished with custom built-in furnishings that better accommodated the arch edge. In the other case the architect chose a single arch of such large size that with an open-plan layout the edge space of the arches could be left free. Both these approaches increase cost, though perhaps no more than the crude framing and partitioning typically employed. I have considered a middle-ground solution where the arch would be sized such that the edge of the arch could be enclosed in 6'-7' tall cabinet walls that would serve as the primary utilities enclosure flanking an open-plan space. In addition, I have considered using a much recessed window wall arrangement allowing the arch to shelter adjacent porch spaces and provide more moderation of solar gain. This could be made even more attractive by using an angled cut along the arch end to create a sinusoidal canopy form. To further reduce the sterilized look of the steel, I have considered an acid treatment which would cause the exterior of the arch to take on an oxide coating giving it the appearance of a more organic material. This would do well to make the structures blend into the color themes of the natural environment, though the increased solar gains caused by reducing the reflectivity of the galvanized metal may be counterproductive in a desert climate. In any case, it's clear that with the steel arch we have a very practical and economical means to spacious and comfortable non-toxic housing -almost as versatile as pavilion architecture but with potential for earth covered use and perhaps much cheaper.

rusted steel arch study

So why am I not now living in one of these simple homes? That's a question we need to ask the many companies that manufacture these steel arches here in the US because they are what proved to be the chief stumbling block. I do not know if this is something common to companies throughout the world or just something peculiar to Americans, but I have found that once a company here decides what sort of markets and applications it is going to serve its workers and executives become utterly oblivious to -sometimes even antagonistic toward- all other possible uses for their products. To make matters worse, most sales people in the US seem to have utterly no detailed knowledge of the products they are attempting to sell and become dumbfounded when confronted by any questions which go beyond the limits of what company sales brochures already explain. In my first attempt at exploring this type of housing I focussed on the use of these arches for earth covered housing but was obstructed by a chronical lack of knowledge about their own products among all the US arch manufacturers I contacted. Some company representatives would tell me their products could not be used for earth covered structures or had no housing applications even though their own sales brochures said otherwise. Others could tell me almost nothing about their company's products, especially such simple and critical details about what chemicals their metal was treated with or what materials were used in plate-to-plate joints. A few were very well versed in the housing applications of their products and promised all kinds of details by mail -which, of course, never materialized. I grew so frustrated that I abandoned this concept for some years.

Exploring it again recently I was confronted by an even more annoying behavior from the arch manufacturers. Suddenly the lazy and flakey sales representatives I had encountered in the past were replaced by a collection of obsessive hard-sell artists who would pester me incessantly for weeks after the most tentative enquiry. This would not have been so bad had I been getting practical information from these people but, just as before, solid information seemed to be impossible. I could never get any details on materials or even consistent pricing from one day to the next. Often these con-men would call me with offers of new one-day-only bargains and tales of having had orders canceled leaving them stuck with building there had to get rid of no matter how great a loss they were taking on the deal. I had to buy NOW or these great deals would disappear. Then, after a little investigation, I would find these 'bargains' to be nothing more than the supposedly normal pricing listed in web sites and sales brochures. It soon got to the point where I could not determine what the real prices for any of these products were while the pestering by these con-men became intolerable.

At present I have been forced to abandon this promising concept simply because the manufacturers of these arch products are such a nuisance to deal with. One would do far better to recycle some old quonset hut structure than to buy a new one but I have yet to find one in a location suitable to my low-pollution environment needs.