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Comment by jacquesm | Hacker News Reader

When you work with 'prefab' it's not rare to see a structure go up in an incredibly short time, I've seen a house 'erected' in less than a day. In the morning there was just a concrete pad and in the afternoon they were busy connecting the electrical wiring.

Still, that does not detract from the very impressive performance here. A carpenter from Canada once remarked that if a million guys all swing a hammer once that's a lot of work done. Throwing 200 workers at this likely didn't hurt either, the logistics and the choreography are what impress me most about this.

if you watch the video wait for the covering of the outside, it's like watching a slowed down flood-fill but with real life hardware. In spite of the 'no work injuries' reported some of the stills had me cringe, I'm pretty sure that a building inspector or safety officer on a crew from the US or Canada would have had a heart attack on the spot.

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I wonder why prefabs houses aren't more common.

A friend of my parents was building a house. I asked him if he considered prefab, he had no idea what I was talking about.

Prefab has a bunch of hurdles and it's kind of a chicken and egg problem right now.

A friend of mine used to work at Michelle Kaufmann's firm in East Bay, and what would happen is that there is such a low volume of prefab orders that they can't get the costs down enough to justify building prefab. Plus it's not standard "from scratch" construction, etc. It's really sad, and the firm shut down for a while in 2009 (I think they're back now though).

Can you explain why "not from scratch" construction is a bad thing? AFAIK most houses these days are built from cookie-cutter plans.

Sorry, yes most houses are built from cookie-cutter plans. I guess I meant from scratch in that they're mostly built up with wood framing (simple to do), vs a lot of prefab which may require welding and more specialized skills to assemble the panels (harder to do, or at the very least less conventional).

In the US yes. In Europe most new houses use a concrete inner structure with a brick facade if they're family sized houses.

That makes them particularly well suited for prefab, a whole wall segment can be constructed including isolation, ducts, windows / doors etc and hoisted in to place by a crane in one movement. Because the brick is laid in the mould a bricklayer can work on a gantry under a roof instead of in the open air which means year round bricklaying instead of only when it's not freezing or raining (you can't lay brick in pouring rain).

Because the wall segments are made on a guaranteed flat surface a section is always going to be perfectly straight without any measurement at all.

Note that these are full bricks, not the typical 'slices' of brick used to give US houses a brick-like appearance over a wooden interior ('brick siding').

Ah that's great. I'm definitely slanted because of my experience in California, where earthquake regulations basically mean no masonry construction ever, and very rarely anything other than wood framing for residential houses.

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