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GBlist: Re: Housing Costs
On 8/16/97 7:00 AM Barry Goldberg wrote:
>Our cohousing group is reaching the point where we have to consider our
>decisions on what construction technologies to use. I'm trying to put
>together a chart comparing costs and other considerations for the
>options we are looking at. I know trying to compare square foot costs
>for diferenet technologies is very crude and inaccurate and will vary
>because of where we live--southwest Colorado. It can help give us a
>picture of what's realistic and affordable though.
If you come up with such a chart, please share it. I've done them for
specific projects, but never in a general sense. Frankly, due to the
many variables, some of which you allude to, I agree that its not
possible to make general and accurate comparisons. In the alternative
literature, many claims are made ("Build your straw bale house for
$20/SF") but these claims have minimial relevence unless one exactly
duplicates the project alluded to. (I wrote an article in the current
issue of Communities Magazine which describes this very syndrom; its
called "How NOT To Build Your Own House").
Having said that, here are a few general comments. This is not going to
be what your group wants to hear, but education is an important part of
the process.
1. The ONLY way to compare costs is to design a sample home, and then
bid it out to all the contractors who do the different methods of
construction you are interested in. This requires blueprints, and more
time and effort than most people are willing to expend. Claims,
estimates, comparison charts, and whatnot are all fluff; actual bids are
the only reality for your situation, using your design, in your locality.
2. As I said befor, beware low-ball claims; they are usually not
comparing apples to apples.
3. Here's an observation that will speed up your process: "adobe",
"stick-frame", "strawbale", etc are all descriptions of *wall systems*.
The rest of the house may be identical. Since the walls account for only
about 15% of the total cost, all the different building systems affect
the overall cost of the structure far less than one expects.
4. My favorite observation to clients: An efficient *design* is the
easist place to save money, not in the method of construction. Adobe
houses for example, can cost far more or far less than a stick frame;
the design causes the cost to vary more than the material. And, the type
of finishes, exteriors, interiors, and appliances chosen will affect the
cost even more! Thus, even the best comparison charts will never come
close to estimating final costs a house (unless, as I said, an actual
design has been let out to bid).
5. You requested "square foot costs" - don't forget "operating costs" and
"lifecycle costs". It makes a huge diffference. Repairs, maintainance,
and energy requirements all affect your bottom line, and vary widely.
6. Stucco. Thats the key. You'll never read this in any book, see it in
any magazine, but its the insight you'll want to remember. All the
alternative wall systems are stuccoed, and thats where the money is. The
wall systems themselves are usually cheaper than stick framing, but
stucco can cost a bundle, and varies hugely depending on how you do it,
so don't miss this. If you DIY, and use real mud then it costs almost
nothing, while if you sub out the standard 3-coat application, its a
fortune, which is why these comparison charts will always be so
incomplete. If a framed house uses an EIFS, then the cost instantly goes
right up to that of any alternative system, so have fun comparing.
Finally, here's my shoot-from-the-hip, personal comments on your list ---
>What I want to compare is the following, in terms of square foot costs,
>ease of construction, options for sweat equity and owner builder
>participation:
> *standard stick frame construction
Buy pre-manufactured homes instead; in terms of money and time,
certainly the best value today of anything. No kidding.
> *energy efficient stick frame construction
If not factory built, then this is the only way to stick frame. Bottom
line is cheaper than standard method.
> *straw bale
Wonderfull buildings that work well. Contrary to how people tend to
think, this is largely a SUBjective decision; people relate to the
"Three Little Pigs" story in different ways! Certainly costs a little
more than stick frame, but is much better both in terms of aesthetics,
quality, and performance. Is often built by owners, with no permit,
using volunteer labor, and with minimal finishing, which lowers the cost,
thus fooling other prospective owners. Could be problems doing a small
subdivision, due to limited materials and subcontractors. Not always
easy to obtain mortgages, fire insurance, and building permits. If
permitted, then it will probably have to be timber framed, which uses as
much wood as efficient stick framing.
> *sraw clay
If you have a few years to spend, this produces an incredible building
with great heart and soul. I couldn't help but note, in India they don't
build this way because its too labor intensive! A sobering thought
considering our lifestyles.
> *earth block
> *adobe
> *poured earth (rammed earth)
I have run the numbers on these three, and they are almost identical.
Again, I think it comes down to what people *feel* good about. Earth
construction obviously works really well, is well accepted (in the SW),
and one can even find subcontractors in your area to do it all. The
problem with these is insulation; nowadays one adds foam to the
exterior, or (in the case of earth block) builds double walls and fills
in the space with insulation. Prior to our current standards of comfort,
the pure earth walls sufficed on their own. Like straw bale, one loses a
lot of sleep during the construction phase if a period of rainy weather
sets in.
> *anything else
* Insulated concrete forms. This works quite well, has no drawbacks
(except the high EE of cement), and the owner can DIY. Subjective issue
again: most people hate the sound of "concrete", and don't want their
house made of it.
* Concrete block. If you run the numbers, you'll find that its actually
cheaper, easier, and stronger to build an adobe house out of CMU's. Once
its stuccoed, you can't tell the dif.
* Hebel Block (someone mentioned this yesterday). Costs a fortune,
because Hebel somehow hasn't really gotten going in the US. Nice
product. An entire cohousing community in Australia is built with Hebel
Blocks.
* Various other alternative blocks. There are too many varieties to
comment on.
* Manufactured houses. The best value, although subjective sentiments
will totally rule this one out for you.
* Pumice-crete. After annoyingly thorough research, this is what I'm
doing. Integrally structural and insulative at the same time; easy
application of 2-coat stucco.
* Concrete. My personal idle thought: figure out a complete wall system
that integrates structure, insulation, and aesthetic finish with a cost
effective method.
Buzz Burrell * buzz@diac.com * 4439 Driftwood Pl, Boulder, CO 80301
Project Manager: Geneva Cohousing Community - 176 acres N of Lyons, CO
Owner: Bolder Building - solar adobe house finished 7/96
- pumice-crete house began 2/97
Co-founder: Colorado Friends of Tibet - hosted The Dalai Lama 5/97
* * * * * * * * * * *
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