Friday, January 31, 2014

Prefabrication experiments - 1 - USDA Forest Service

For multiple reasons, sustainability, reduced on-site craftsmanship, and optimizing resource consumption, prefabricated systems for housing are back in vogue. For the  reasons mentioned above or for more selfish reasons, namely architects finding it to be a good way to push a  modern aesthetic, it is a great time for prefab.

As global demand for housing increases, on-site productivity stagnates, capacity to serve demand decreases, prefab systems’ market share will increase. This potential for a renaissance in prefab and industrialized building systems will also be driven by BIM (building information modelling) and lean construction practises.


As demand increases, it becomes necessary to frame current production techniques within a historical context to reveal possible strategies that were brought forth in an era of similar confluences to solve a housing crisis. We will feature prototypical, experimental or marginal projects that explored prefabrication as a building method capable of increasing production and quality while offering reasonable cost quality housing.

Our first project is the Prefabricated house system developed by the forest product laboratory in 1937. A collaboration between the United States Department of Agriculture Forest Service and the University of Wisconsin, it was a stressed skin panel system. The report authored by R.F. Luxford states that the project was developed as a solution to high demand for low-cost reasonable quality housing in the context of increased cost of labor. The report also mentions that in 1949 about 30 000 prefab houses were produced in the US by 100 manufacturers, 3 000 000 units !

The wood stressed panel system caught our attention as a fairly simple system based on a «box-girder» structural strategy that optimises strength while reducing weight and resource use. The second item that merits a second look is that the system is used for floors as well as wall assemblies, which reduces the total height of the building and further optimizes resource consumption reduction. The patents for this system were dedicated to the public. This generosity is a welcomed form of sharing in a world of open source collaboration.  For more information the report is available on the web at  http://www.fpl.fs.fed.us/documnts/fplrp/fplrp18.pdf

Experimental housing units by the USDA and US Forest Service _ see link