Buckminster Fuller used to ask "how much does your house weigh?" It is still an important question, a reflection of the size and amount of material going into our buildings. In the Recreational Vehicle (RV) world, it is particularly important, since every extra pound you pull behind your car reduces your gas mileage. It's one of the reasons that the RV world is so interesting; they are at the forefront of designing for small spaces, using transformer furniture, using fewer resources in fuel and water and electricity, since you have to carry them all with you. There are a lot of lessons to learn from these things.
The Alto 1713 is one of the more interesting trailers around. It starts as a teardrop, the aerodynamic trailer design that has been around forever; they are easy to pull, with 75% less drag than a conventional trailer. The builder writes:
Faced with the steady increase in the price of gasoline and the social responsibility we all share to save non-renewable fossil energy, Safari Condo wanted to design ultra-light travel trailers with the lowest possible drag coefficient. Travel trailers meeting these two criteria could then be readily towed by smaller vehicles. Even more environmentally conscious, Safari Condo also wanted its materials selection to be not only lightweight but for the most part recyclable.
This thing is seriously light. Built with aluminum bed and sandwich panel walls, the whole thing weighs in at 1683 pounds. With that weight and that minimized drag, just about any four-banger could pull it. Everything inside is built with ultra-light materials, even the furnishings; "Rigid and ultra-light sandwich panels are integrated into the bed cushions, while the entire bed structure is made of aluminium extrusions."
But the show really starts when you park this thing. The one problem with teardrops is the lack of space inside toward the rear. This unit has a retractable roof that pops up to make the entire floor useable, with 6'-10" headroom.
The seamless aluminium roof is built in a single piece of curved Alufiber/aluminium sandwich panel. It is opened and closed by a pair of electric linear actuators. Its crescent-shaped windows are tinted tempered glass.
The plan has a lot of lessons for tiny house builders; there are many options in how one uses the space.
There are in fact two places one might sit down and eat; the single bed at the front converts into a smaller table and seating for two,
the double bed at the rear converts into a larger seating area, in the part of the trailer that would be lost, or at least severely constrained, in a conventional teardrop.
At night, the table drops down to create a large double bed.
The kitchen is small, but with the small table added in as workspace would be adequate.
I am dubious about the topless toilet enclosure, but they don't have much choice with a pop-up roof. A version with a fixed roof could have walls that went to the ceiling. In fact they make a version like that, where they also offer a shower.
I find it amazing, how much stuff they can squeeze into such a small space. Besides sleeping for three, a kitchen and a sort of bathroom, there is room for gray water, black water, fresh water tanks and batteries. There is an option for covering the roof with flexible photovoltaics delivering 68 watts. They really pack it in; there really is a lot to learn in the trailer park.
More at Sierra Condo.
This video from Discovery Canada's show How It's Made is illuminating; this thing is essentially built by hand. They lay up the sandwich panels, vacuum form them into the curved shapes, cut out all the openings by hand. You would think that it was made in heaven for a CNC router but there is almost nothing automated.