http://hexayurt.com gives some notion of how radical that shift could be when it arises. Industrial panels (of whatever kind) directly into owner-build housing. Free Hardware. You may laugh, but half the world lives in cinderblock-and-tin-roof shacks and worse.
Nobody said the innovation had to start here, or look like what we do now.
Apparently it takes only a couple weeks for one man to build a house, but the labor involved in general contracting to get the subcontractors to do their thing exceeds the time spent swinging a hammer. He sub'd out to dig and pour the foundation, some electrical, gas, some plumbing...
For those of a certain generation it was how you proved to the employer that you could complete long complicated projects, basically the equivalent of completing your college degree (which was hard to complete during WWII)
This is still done on a regular-ish basis for large garden sheds and garages. Home Depot and others will dump a pile of wood at your location with some plans and bulk pack of nails and other hardware and a weekend or two later you'll have a garden shed.
The permitting and inspection process is more about revenue generation than safety.
That's interesting stuff, but all we really need to get the ball rolling is to remove the financial and regulatory speed bumps that prevent people from buying prefab homes. It's not like it is some kind of mystery how to reduce the cost of building a home...
EDIT: I was thinking more in terms of the way lending and building ordinances very strongly favor building a house on site vs. trucking it in, as opposed to the really... insightful... stuff you guys have mentioned.
Agreed! Just remove all those pesky restrictions about fire safety, earthquake safety, tornado safety, electrical safety, and you can put that house up for real cheap :)
Edit: On further thought, I see I've been slightly misleading/unclear. When I started taking about the manufacturers of the problems, I wasn't meaning just the building materials that have failed, I also meant the regulatory systems and practices that were poor.
Yeah... but a lot of that is we don't /want/ housing to get cheaper. Most voters will vote to keep housing more expensive.
Compare the £3500 I paid to have a new boiler fitted to what £3500 would buy you in technology these days.
 Can't DIY it: I'm legally required to have a Gas Safe fitter to touch anything related to the gas supply.
 Replacement of open vented system with combi. Replacing like-for-like would be much cheaper, I know.