In my last post, I mentioned how it often seems that "prefab" is conflated with "green" when it comes to sustainable home design. While I definitely don't buy that one implies the other, there are, nevertheless, a number of recent projects that exemplify both. Here are 3 of the coolest examples.

Global Sustainable Home [GSH]: Self-sufficient Prefab

Greggory Cates and John Farag's Global Sustainable Home is constructed from factory-built components [sectional pieces] and can be assembled in about a week. Typically, pre-fab homes are constructed atop a site-constructed foundation, but the GSH's foundation is built from a series of [also prefab] helical piers that can be installed with minimal disruption to the site.

Prefab is only part of what makes this project green. A pv canopy shades the house while generating 100kWh of electricity per day [assuming it's installed within 30 degrees of the equator and the weather is nice]. The GSH also comes equipped with dry-composting toilets and an internal grey-water potable system, to which sinks and showers are connected. It seems that the GSH takes the logic of prefab beyond manufacturing components, to include the water and sewer services, allowing the structure to be surprisingly self-sufficient.

Green critique: One-size-fits-all design mentality isn't adaptable to site-specific circumstances, meaning that the structure doesn't respond to local cultural, economic, or environmental conditions.

weeHouse: Really small [and beautiful!] Prefab

Alchemy Architects's line of "weeHouses" blend custom, site-specific design with off-site construction. Beautifully detailed and hand-crafted pre-fab modules are combined and modified in interesting ways, depending on individual client needs and site constraints. Designed with passive heating/cooling in mind, the modules can be hooked in to existing utility lines or outfitted for renewable energy use. The new "wee ZERO" prototype boasts pvs for the generation of electricity, solar thermal collectors to radiant floor and hot water heating, rainwater collection and the option of geothermal heat. However, their greenest feature might be the size; adhering to the philosophy "the greenest square foot is the one you don't build" the weeHouse studio weighs in at 400 square feet. While it certainly sets a new standard for high design in compact spaces, it might not work for everyone.

miniHome: Greenest prefab trailer.

Sustain Design Studio argues that the greenest prefab building alternative isn't a traditional building at all, but rather, a mobile dwelling more akin to an RV. The folks there remind us that RV's and Trailers "have a long history of operating 'off-the-grid' - typically in 'camp-like' environments" and the lack of permanent foundation means minimal impact on the land.

The miniHome is built with rigorous material standards in mind; the finished products boast no vinyl, no formaldehyde, no toxic adhesives or finishes, all water- or plant-based finishes, no CFC's or HCFC's, woods from certified sustainable sources, high natural ventilation rate, durability, and low-maintenance. Sustain Design Studio credits the high material and quality standards to the prefabrication process. The miniHome is also outfitted with solar panels and an optional 400Watt wind turbine. Propane, the favorite RV fuel option, is used to power heavy thermal loads like the furnace, refrigerator, and hot water heater.

Downsides? As cool as the miniHome sounds, it's still a trailer. While personally, I love camping and could definitely see myself moving into an RV, it would be remiss to ignore the fact that there is, certainly, a stigma attached to living in a trailer. Positive press regarding new sustainable prefab options is, perhaps, doing something to dispel that stigma by creating an alternative that is far superior to its lower quality cousin, the single-wide. However, these newer greener options are also not as affordable as a traditional mobile home.

Next time, the coolest new idea in prefab: Blu Homes that fold for easier shipping!