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GBlist: a treatise on straw bale



I don't get to spend much time these days replying to this or any other 
list, but I feel compelled to make a few comments in response to things 
that I've read here recently.  First, I'm always disturbed by claims that 
a given building system or material is appropriate everywhere.  This 
position is continually projected on proponents of building systems such 
as straw bale, rammed earth, cob, etc., while most of us who have been 
exploring and working with them for years tend to be very careful in how 
we talk about them and in our characterization of what we do and don't 
know about them.  

I concur to some degree with what John Bower said about the inevitable 
failures in straw bale buildings.  I have been saying for quite awhile 
that I guarantee that there will be moisture failures in straw bale 
buildings - because there are moisture failures in virtually every other 
type of building and I see no reason to expect straw bale structures to 
somehow be immune to this problem.  

On the other hand, I have probably seen as many of the older straw bale 
buildings as anyone.  And I remain convinced that this is a viable 
building system in many different climates.  There are some excellent 
examples of the system, such as the Burke house outside Alliance, 
Nebraska, built in 1903, abandoned in 1956 and still in very sound 
condition in the summer of 1994, when I visited it and photographed it.  
It has very small overhangs (about 12") cement stucco on the exterior 
with no paint, wood lath and plaster on the interior (and yes, it had an 
indoor bathroom and a kitchen).  The baled meadow hay that was exposed 
after 38 years of the ravages of the seasons, where the stucco had 
cracked, showed virtually no signs of decay.  Likewise, the places where 
vandals had broken open the plaster inside did not reveal anything scary 
or gooey.  This 900 sf house was plastered with only mud on the exterior 
for the first five years or so, because the Burkes were planning to build 
a "real" house when they could afford to.  It only took them that long to 
figure out that they were already living in a real house, after which 
they plastered it and lived in it raising 5 kids over a 53 year period.  
They moved out because they wanted a much larger "modern" ranch house, 
which they built for themselves about a mile away on their huge ranch.

I also have visited the two bale structures at Fawn Lake Ranch near 
Hyannis, Nebraska, one built in 1914 and still in use as the headquarters 
of the ranch and another built a few years later with 50's second story 
addition which now serves as cook's quarters, having formerly been the 
bunk house.  The main house has wood panelling in much of the interior as 
well as wood floors.  These are also baled meadow hay (grasses) and both 
structures are in use and serving well. 

I have been in the Scott house near Gordon, Nebraska, built in 1938 and 
one of the finest examples of the Nebraska style houses to be found.  It 
has the straightest roof line, flattest uncracked stucco and plaster 
walls, and like the others, only reveals the bale structure (this one is 
straw and like all the ones mentioned above is load-bearing) through the 
thickness of the walls.  This is true also for the Martin/Monhart house 
built in 1925 (in which I've had the pleasure of sleeping on two 
occasions) and the Pilgrim Holiness Church (1928) both in Arthur, 
Nebraska.  I know of about another half dozen in Nebraska, which date 
from the mid-twenties into the late thirties, that I haven't visited but 
Matts Myhrman and Judy Knox have.  I've seen photos of those other 
buildings and we've talked about them and all appear are reported to be 
sound buildings.

I've visited several others in Wyoming (4) dating from the late forties 
and early fifties, and South Dakota (2) where there is one built in 1921 
using mortared bales (like bricks) and currently used for storage.  
Though one could argue that these are all in somewhat drier climates, 
colder certainly than the southwest, but with less rainfall and humidity 
than the northwest, northeast and the south, there are examples in each 
of those climates that, though some not as old, offer encouraging 
evidence of viability.  

The Burritt Museum, in Huntsville, Alabama, built in 1938 is another 
impressive older bale structure in a non-arid climate (fairly severe 
mixed climate - with an average annual rainfall over 50 inches and an 
average relative humidity over 50%.  It is a concrete post and beam 
structure with bale in-fill and bales used as sound insulation between 
floors (yeah, it's two stories with a basement) and in the attic for 
thermal insulation.  It often snows in Huntsville in the winter and gets 
hotter then hell in the summer.  The building is doing quite well by all 
accounts.  The Burritt is owned by the City of Huntsville and is open to 
the public, so go check it out if you're down there (I've not visited 
this one yet, though I know four people who have and whose opinions and 
powers of observation I trust and I've seen their photos too).

I also had the pleasure of visiting a 1975 baled hay structure in Old 
Saybrook, Connecticut during the NESEA Building Energy Conference 
recently.  This little cottage sits a short distance from a peat bog, 
about five miles from the mouth of the Connecticut River and the coast.  
It has no foundation - the bales, which Ben Gleason who built it 
described as "hay that had gone by" were stacked on slightly mounded dirt 
covered with a layer of plastic and then stuccoed inside and out using a 
stucco mix consisting of "cement and some sandy soil from across the 
road".  I just happened to have my Protimeter Balemaster moisture probe 
with me and we just happened to have a drill and permission to punch some 
holes in the stucco, inside and out, and check for moisture in the bales. 
 What we found was amazing.  This is an occupied house, at the end of 
winter, in a far from benign climate, with virtually unsealed interior 
walls (lots of gaps around door and window frames, at the floor and 
ceiling, etc.) and we could not find any serious moisture accumulations 
in the walls.  The worst place we found was on the north side of the 
building, down within a few inches of the ground, just inside the 
exterior stucco and the reading was 20%!  Most places we couldn't get 
readings above 11%, the minimum the meter reads, and there were a few 
places, like under a window, where we found 14% or 15% moisture.  There 
was NO evidence of decay that was visable or detectable by odor or 
anything else.  

And for contrast, a couple of weeks later, Tom Hahn (the Phoenix-based 
architect who was the lead designer for the APS Environmental Showcase 
home in Phoenix - and no, there's no straw bale in it), who edits The 
Last Straw journal, and I tracked down a bale house in central Phoenix 
built by a Taliesin West architect in the late forties or early fifties.  
Here again, no signs of decay.  In fact, we had a hard time convincing 
the woman who is renting the place that, yes, in fact those thick walls 
contain bales of either hay or straw.  And for good measure, there's a 
post and beam straw bale house in France which was recently restored, 
built in 1921 and the straw is fine, and a baled straw church in northern 
Alberta, Canada that was built in the fifties and at last report was also 
doing well.  I could describe some other buildings, such as the house 
without a foundation or exterior wall finish after nearly 14 years 
outside Tonasket, Washington, in which the bales are also not showing 
decay - because they get wet but they can very easily dry out.  Etc., Etc.

What does that tell us?  Well, we know that it is possible for these 
structures to last as long as wood frame structures in these same 
locations.  We know that none of these older houses used any exotic 
barriers - perhaps the fact that they were not well sealed and had no 
synthetic stuccos, foams, or other higher tech materials in them actually 
helped them survive.  Some if not all were originally heated with wood, 
but many have "modern" gas, oil, or electric heating systems now.  

As John Bower also pointed out, we don't know about the ones that didn't 
survive, except for some photos and various anecdotal accounts of 
structures that no longer exist.  But we have a good collection of 
structures that survive and we are working toward doing some careful 
testing and evaluation of these older structures as well as comprehensive 
testing of both bale wall systems and whole house testing.  If no one was 
willing to build anything but buildings that had long proven track 
records, we would still be living in caves and the like.  

I don't advocate building structures that will likely fail, or cause 
problems for their owners or occupants.  On the other hand, as someone 
else mentioned, we simply cannot continue to build the resource 
intensive, high impact, high cost structures that are the "norm" today in 
what I recently heard referred to as the "over-developed" world.  It is 
really imperitive to find ways to use the materials we have in abundance 
(and straw and earthen materials are certainly in this category).  In 
fact earth and straw have about as long a history of use together as any 
building materials I can think of.  We have developed some very peculiar 
and dangerous notions in the over-developed world about our buildings, 
what we need, how little we should ever have to think about or do 
anything to them, and how detached it is permissable to be in regard to 
the real impacts of what we do.  I love technology used well and despise 
it's mindless application in the pursuit of ego gratification, greed, or 
sheer laziness.  I define appropriate technology as the lowest level of 
technology needed to do what needs to be done well, as opposed to our 
cultural bias to use the highest level of technology (and its 
accompanying high level of unintended consequences and impacts) we 
"think" we can afford.  What can I say, I like mud and straw.

That said, I will readily admit to living in an under-insulated concrete 
block house in Tucson. Arizona, built in 1952 and requiring a fair amount 
of energy to heat and cool (it's what I could afford).  But I haven't 
gone out and scraped off another acre of desert to build a new one for 
us.  And when I need to reroof (sadly/gladly still a few years away), 
I'll have the opportunity to extend the eaves and wrap this house in 
bales and use an earthen plaster - and I'll do it without hesitation when 
I can. 

Talking and exploring moisture issues with George Tsongas (at Portland 
State University in Oregon), Bob Platts in Ottawa, Canada, as well as 
conversations that I've had with Terry Brennen, Marc Rosenbaum, and lots 
and lots of others, have lead me to the place that I think it is possible 
to design and build bale structures successfully anywhere that it is 
possible to build wood structures.  Whether that is appropriate, 
cost-effective, energy- and resource-efficient, etc. depends on the full 
range of variables that need to be considered for any building in any 
climate or location.  Nothing works well everywhere.  

Enough for now.



David Eisenberg
Director
Development Center for Appropriate Technology (DCAT)
PO Box 41144
Tucson, Arizona 85717
strawnet@aol.com
Note new fax number
(520) 624-6628 phone
(520) 798-3701 fax 


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