March 2, 2011
I recently mentioned the construction of Greenfab‘s model home in Seattle, and that home is now complete. I think you’ll agree, it’s just as warm and handsome as the renderings. The six-module abode — on target for LEED Platinum and Built Green 5-Star certification — has 1,790 square feet with three bedrooms, two and three-quarters bathrooms, a separate mother-in-law space, a planted rooftop deck, and an urban chicken coop.
The prefab is located at 1827 S Lane Street in the Jackson Place neighborhood of Seattle. Owner, project architect, and general contractor, Robert Humble of HyBrid, will take the keys soon after Greenfab gets some time to share the new home with the community.
The home left Guerdon Enterprises’ factory in Boise about 60% complete in December 2010. Altogether, it was built in a factory in five days and finished on-site in 45 days. Johnny Hartsfield, owner of Greenfab, told Jetson Green that his company has the ability to deliver homes up to about 90% complete but wanted to handcraft some aspects of this first home to make it special.
For instance, you may notice custom-milled, polished, wide-plank plywood floors below. Also, Greenfab enlisted the help of Greenhome Solutions for EcoTop counters on IKEA cabinets and recycled-content tiles in the bathroom shower. Greefab recycled existing concrete by filling gabion baskets to create a custom retaining wall system. These landscape walls sport a contemporary look and seem to be growing in popularity in the residential context.
To save water, a 1,400-gallon tank harvests rain for on-site irrigation and toilet flushing, while three 300-gallon basins filter and treat shower, sink, and washing machine water for landscape usage. The home has one of the state’s first grey water systems.
It’s all-electric and outfitted with a Fujitsu mini-split heat pump, GE Hybrid heat pump water heater, energy recovery ventilator, Convectair backup heating, and energy-efficient appliances.
In the future, a 2.4 kW photovoltaic system will be installed to offset about 23% of annual energy consumption. In order to approach net-zero energy levels, the system needs to grow to a size of roughly 6 kW.
Hartsfield, reflecting on the project, said modular construction offers some undeniable pluses. Benefits include timing (do site and factory work at same time), material integrity (keep the home secure from weather prior to completion), quality (build on jigs for strength and precision), and conservation (control to minimize construction waste).