A great piece in the NYTimes on the history and future of factory-produced buildings:
But the most notable difference between the United States and Sweden is regulatory. US building codes attempt to make buildings safer by specifying exactly what materials should be used and how (prescriptive code). In Sweden, the government does this by setting goals and letting builders come up with a way to achieve them (code of practice).
So, for example, US building codes determine the thickness of drywall that should be used for fire resistance, how many layers are needed and how many nails are needed to attach them. In Sweden, the code requires that the wall must be able to withstand heating for, say, two hours, and allows engineers and manufacturers to find a way to achieve that. The administrator’s job is to check the developer’s work.
The result is both fire resistance and building safety, but in the United States, every residential building needs to be licensed. During construction, work often stops for inspectors to conduct visual inspections from time to time. That contributes to a stop-and-go pace that frustrates everyone except the lenders, who earn interest on the financing. The Swedish codes require more work up front where manufacturers have to demonstrate that their methods work, but factory practices that comply with the code of practice can be approved. This encourages innovative solutions and leads to less waste.
As an example of how functional code leads to innovation:
..Before Sweden adopted its performance-based code in 1995, wooden buildings were limited to two stories; almost overnight, wooden structures could be as tall as engineers could prove safe.
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