Cob: Re: Re: Time and cost?

[Vicki Wicker]

I'm not seeing how you get a strawbale house costing 20% more than 
conventional stud house. We're working on a house plan now and just 
standard bat insulation was going to be double the cost of the bales for 
half the insulation value. Foundation and roof essentially the same, as 
well as fixtures. So, the cost difference would be what it costs to side 
and sheetrock a stick frame to what it costs to stucco the strawbale. If 
you use earth plasters, I think strawbale will come out ahead with higher 
insulation.
What I see people doing with strawbale is putting up their walls, and 
having their foundation and roof professionally done. Whereas they wouldn't 
undertake trying to build a framed house. Also, floor is a huge expense. We 
did an 600 sq ft. earth floor, finished, for a load of fill ($115) a load 
of sand ($115, still lots left),  @$50 worth of portland and probably $30 
worth of linseed oil and mineral spirits. Estimate 50 cents a square foot 
for the entire floor system. Nothing in conventional construction comes 
even close to that.
We debated long and hard about cob, because we have good cob soil here. But 
its the thermal mass thing that has worried us. Our summers are extremely 
hot and extremely humid. My concern was that by late august we would be 
living essentially in a self made oven. Once those wall heated up, they 
wouldn't have a chance to cool down until maybe November!
But, we've only completed our bermed basement section (concrete 
block/living roof) as of now, so we're still open to possibilities.
At 07:36 AM 10/31/01 -0800, chita jing wrote:
>     I wonder if anyone's used both systems? That would be interesting to
>hear.
>
>     Meanwhile, from simple reading and with more familiarity with normal
>stick building -- I'd say no way is straw bale easier with respect to time
>or cost. After reading all the lists and books and seeing various
>residential projects for years, IMHO, cob is probably the best system for
>anyone venturing out from stick built construction. It is also one of the
>most affordable, all things considered. From what I can see in the Bee book
>especially and watching (similar) adobe construction methods, cob has a low
>landed (net) price as well as being easy to understand and do. Cob type
>buildings have survived in Europe for hundreds of years (as have adobe). I'm
>not sure at all about straw bale's longevity. They seem to be relying on the
>shell material they slap over the bales.
>
>     If waiting for cob to dry is a burden, why not make the first building
>the shop/barn, where you can store furniture and materials and live out of a
>car/trailer/tent for as long as it takes the main house to "cure" of
>moisture? There are worse things than living out of a Butler or Steelmaster
>building for a year. You can sell the building (and trailer) afterward.
>IMHO, that's recycling without any need for apology.
>
>     One of the major problems with "alternative" building systems is the
>lack of experienced, cheap labor. Stick built construction has 5,000 books,
>videos, classes, retired-after-40-years-building types running around. Many
>alternative builders start selling a seminar within ten minutes of deciding
>to build. A practise has arisen the last twenty years of putting students to
>use in these buildings. They - like their mentors - can make mistakes simply
>because the general level of experience is so low. Mistakes go so far as to
>invade books - even books by learned physicists. All in all, mistakes take
>time as well as money to overcome.
>
>     For speed, I've seen nothing that beats buying a steel framed building
>from a professional fabricator of same and filling in the surfaces. I think
>it's feasible to put up a 1,000 square foot livable structure within a week.
>Stick built construction can be even faster than that (per square foot).
>Timber framed buildings could be as fast as steel but rarely are, if their
>writings are typical of actual construction practice. Timber framing also
>takes considerable skill to do well, compared to the high Forgiveness Index
>in cob construction.
>
>     Affordability is not trivial. Straw bale is claimed to cost "only" some
>20% more than stick built. Affordability is a MAJOR issue with all building
>systems, IMHO. Right off the bat, I can't think of a better system for
>amateurs on a budget than cob. Buying all the supplies and tools, even
>buying the videos and books and adding that to the budget as expenses
>(rather than the capital items I believe they really are) -- so far, I think
>cob is winning on all counts.
>
>     Getting up a "livable" structure is a far cry from building a beautiful
>structure. Let's not confuse "getting it up without any walls falling down"
>with building a dream house. All the alternative systems need more design
>attention, IMHO. That's a whole other dimension of building which isn't
>addressed nearly enough. I've often thought artists should be recruited more
>than artisans. It's one thing to build an air-free brick, it's another world
>to make it pretty.
>
>     Houses are also more than surfaces. People need to concern themselves
>with plumbing, electricity, lighting,  trim, ventilation, moisture control,
>etc. It's likely to take several installs to make putting in a new bath a
>casual thing. I recall especially the last few "alternative sewer"
>installations I saw. Ugh. Mistakes in sewage handling are really
>devastating. Even worse than the owner-designed cabin I once toured where
>everybody over about 5'6" hit their head on a beam at the top of the stairs.
>
>     At this moment, I really think cob has the best overall approach and
>tool set. It's easy to comprehend, has a long history of standing up to
>weather (and that does count with me, I really dislike the idea of trying to
>repair a falling down wreck in my old age) and the costs are also
>competitive in most areas.
>
>
>
>----- Original Message -----
>From: "drhelp" <drhelp at shaw.ca>
>
> > From what I've seen, strawbale would move faster and allow you to
>accomplish
> > your goals within a more reasonable time frame than cob. Is that the
>opinion
> > of others on the list? Diana
> >
> >