Flutterby™! : Prefab houses 2004-05-12 16:08:57.77834+00

Prefab houses

2004-05-12 16:08:57.77834+00 by Dan Lyke 9 comments

This one's for crasch: The Fab New World of Prefab Houses: SF architect brings eco-friendly, modernist design to the average home buyer. Unfortunately, they don't have pictures of the actual thing, just renderings of designs, and the floor plans look pretty trailer-ish. There's no reason that prefab panels couldn't be used to make prettier houses than what they've got in that article and the links from it.

This isn't really all that new, is it? We've been looking at pre-fab houses for years (they call them Modular Homes up here). The floor designs range from very trailer-ish to not so much, but it would be great to see more materials like they talk about in the story.

Yeah. My paternal grandparents lived in one of those "two halves spliced" homes put on a real basement and foundation, and I thought it was a perfectly serviceable home, and looked fine with a few things to bring it out of "rectangular box" mode.

I would like to see more alternative building materials. For instance my dream house will have a kitchen with sloped sandblasted concrete floors (like a commercial kitchen), and if stainless steel fixtures are too expensive then cast concrete countertops sounds like a great relatively inexpensive building material, and one that if finished properly could give marble or granite a run for their money in terms of practical use (a large smooth surface with thermal mass for dough and candy making).

I'm not sure I like the design philosophies espoused in A Pattern Language

, but one of the construction materials they talk about there is vermiculite in concrete for the great insulating properties and relative ease of wall layout and construction. I'd love to hear more about some of the techniques akin to that used in commercial construction (precast wall segments, things like that) can be used in energy efficient residental homes. This "stick built" stuff is expensive, inefficient, and maintenance prone.

if stainless steel fixtures are too expensive then cast concrete countertops sounds like a great relatively inexpensive building material

It might sound like it, but your intuition would be wrong.

Having just remodeled a kitchen and chosen countertop material after a long bit of contemplating, we chose granite. Quoting from a good article on concrete countertops:

There are also some downsides to concrete countertops, including hairline cracks, the inability to seal them fully and completely (resulting in a need to use many layers of epoxy and wax, which make them look a little cheezy and in need of a re-sealing in a couple years), the fact that they scratch and always need a cutting board, and the unfortunate fact that the finish is damaged if you put a hot pot down on it or leave oil or lemon juice on it.

Before we redid the kitchen, I mentally observed myself cooking for a couple weeks and noticed that I often put a pot down on the (awful, stained, beat up, old) tile countertop. That fact alone sealed my decision to go with granite. I like the idea of concrete, but its time is not yet here as an affordable, usable countertop material.

Wow. I read an article on casting your own in some yuppie home improvement dead-trees publication, and it looked nigh to trivial. The big deal was finishing with a sand blaster, and making the parts small enough that they were manageable on the install. Scratching would be an issue, though, and would push me towards finding a restaurant going out of business for fixtures, a slab of marble scarfed from something (maybe a used high-end coffee table) for the candy and pastry making portions.

I have a few pieces of left-over granite from our countertops that it seemed worth keeping at the time. While they aren't large enough for a countertop, there's a couple of decent-sized pieces, if you're interested...

Hmmm... Something that's, say, the size of a large cutting board would solve all my needs for the foreseeable future... I have a small marble slab (probably 2'x1'), but something a little larger and a little thicker (for thermal mass) would be nice.

Thanks, Dan! I love to see higher quality, energy efficient modular housing. I wonder what their house cost in toto -- the article doesn't say.

The article mentions housing costs of $110 psfoot instead of a more usual $240 for customized houses. I wonder what the real costs are, when you factor in land, taxes, city inspection fees, bribes to the alderman etc. I've always thought that we could turn out very interesting manufactured housing using advanced techniques (green or otherwise), but that there are too many vested interests in labor, materials, neighborhood image committees, local politicians and what not to be more interesting. For example, prefab housing is largely forbidden in Chicago, to mollify the construction unions. (plastic piping is also verboten, but still done). Hell, in the 1950s they tried to outlaw wallboard, at the behest of the Brotherhood of Plaster Schmerers.

I also have a question or two: How would these houses work in a harsher climate than the Bay Area; say, Illinois? Also, can they be easily remodeled if you have triplets? The famous Lustron all steel houses of the 40s were great, but you couldn't add on a room without getting an oxy-acetyline torch. You also needed to hang pictures with magnets. Imagine your Picasso held up by some of those "Beautiful Niagra Falls" magnets you got on vacation last year!

Try reading through parts of a building code some time and see how many of those things are in there for special interests. Nothing is as full of protectionist scams as real estate, from planning to construction to sales.

I think that $110/ft.^2 number was independent of land, and as a low number sounds suspicious. I looked at a project a little while ago which essentially involved gutting a shell, doing some structural rebuilding, and remodeling, and the high range of the numbers we came was $80/ft.^2, my dad, who's been making his living doing moderately high end remodeling in a slightly cheaper area of the country, said $40/ft.^2 was a good starting ballpark (although that was probably in the context of knowing that this was going to become rental units).

Now in the Bay Area land costs are well over $1M/acre (accounting for the shell we were working with, one of the several reasons I decided against this project, which was probably a mistake, was that we were basically being asked to pay $1.6M/acre...), so spending an extra several tens of dollars per square foot on the house is a fart in a windstorm, which is probably why many Bay Area houses are fairly well decked out. And there's a local "bamboo flooring discounter" that I've seen on my commute which has a huge banner advertising said product for 4-5 times the cost I've seen it for elsewhere, even if you factor in transportation. So it's also possible that those paying $240/ft.^2 aren't being the savviest of consumers.

(I'd say "much like those who think that 8x income is a sustainable house value", but I'm becoming less sure of myself on that matter...)

I don't know about exterior finishes, but if you're willing to accept different aesthetics it's trivial to build domiciles with better R-values than traditional stick built spun glass insulated homes. Windows are still the major leakage places, but if you have problems with too little airflow (one of the problems as R-values rise) then perhaps that's a place to accept some wind.

And commercial buildings use a lot of these techniques, especially in terms of exteriors, so it's not like they're totally untested.