But miniHome's differences from the conventional trailer are what's most interesting about it. For one thing, it's easy on the eyes. "Trailers are ugly, and susceptible to mould, and there's too much vinyl," Mr. Thomson told me last year, when I first heard about this project.

The finished prototype, which I saw last week, is a handsome composition, in its efficient, no-nonsense way. The layout of the interior is plainly elegant, with a good kitchen equal in amenities to what I have in my condominium apartment, and a queen-sized sleeping loft that frees up circulation on the main floor.

It's also easy on the nose. MiniHome has no vinyl at all, no products containing formaldehyde, none of the stinky adhesives or finishes used in conventional trailers -- hence no toxic new-car smell. Instead, the interior has the wholesome fragrance of Baltic birch. (Other finishes include ordinary kitchen laminate and a non-aromatic surfacing material made from the wood of rubber trees.)

From Mr. Thomson's standpoint, however, the best things about the project are that it has been created (as his website proclaimed) with "a clear conscience," and the awareness "that we produced a building of enduring beauty from materials and methods that have the lightest burden on our ecosystems."

But the operation of miniHome will also make a notably small footprint on the environment. Like any house trailer, it requires no foundation. It needs no hookup to the power grid, though such a connection is provided for (if, for example, a miniHome is situated in a trailer park).

It features solar panels and a small wind turbine to provide electrical power, and an on-board propane system for heating, cooking and refrigeration. Mr. Thomson's idea, effectively realized in this project, has been to compress all the technologies and supplies needed for living into a self-contained item that can be set up almost anywhere.

During the early days of developing the miniHome scheme, Mr. Thomson imagined that the target market would be at the edges of civilization, in, let's say, remote mining or oil-drilling sites. But in the runup to last week's market launch, the designer set his sights on a broader, continent-wide range of consumers, which has turned out to be a wise move: In the first week of sales, five customers put down money on miniHomes (which are priced at $119,000), and hundreds have expressed strong interest in the product. The people who have made firm commitments, Mr. Thomson told me, come from as far away as California and British Columbia, Maine and Alberta, and they have a variety of uses in mind, including primary dwelling and weekend cottage living.

With any luck, Mr. Thomson and his partners at Altius Architecture - he recently entered into a business arrangement with the Toronto firm - could find a lively market match for their product. While more expensive than the usual mass-produced house trailer, the cost of miniHome is far below that of a custom-built cottage or even a very small house. And the numbers are there: Fred Hallahan, an American trailer industry analyst, recently told me that, despite financing headaches, zoning restrictions and entrenched snootiness about trailer park living, about 8.5 million Americans and 360,000 Canadians live in mobile homes. Of this large population, quite a few will likely find miniHome's combination of enhanced comfort, environmental sustainability and affordability to be very attractive.

MiniHome is a bright spot on an otherwise cloudy horizon. Though architects love to design it, prefabricated housing of the more high-end and less portable sort seems to be languishing. Many beautiful designs have come off the drawing board, but, so far, nobody has figured out a way to cut the cost of prefab below that of custom-built housing. MiniHome, on the other hand, seeks a place within the well-established mobile home market, bringing to it a fresh look and the kind of environment mindfulness that more and more consumers nowadays are demanding.

jmays@globeandmail.com