Date: Wed, 08 Aug 2001 09:00:31 -0700
From: Joelee Joyce dawnaz@...
Subject: letter from Tom Ososki
The following letter was sent to Matts and Judy who handed it to me to
field the request. This was during the time of Mildred's passing, so it
has been sadly neglected. So anything you can do would be appreciated.
DAWN / Out On Bale By Mail
6570 W. Illinois St.
Tucson, AZ 85735
Tel: 520 624 1673
Web site: http://SustainableSources.com/dawn
------------letter & proposal follow--------
From: Thomas Ososki
Amhara Beueau of Works & Urban Developmetn (BoWUD)
PO Box 725
Tel: 08 20 54 38
Dear M & J:
I am an American architect working in Ethiopia for two years. Some past
straw bale experience has led me to start a project of reasearch whether
straw bale construction is a viable option for construction in this
country. It is an exciting project that has the possibility of helping
many people. See attached proposal for more information.
As BoWUD begins this project there are two larges issues that have
appeared to us. One, the main physical obstacle to our project is the
lack of a baler in our region. It looks like we are going to have to
design and build a manual straw baler. If we knew of other designs
already built, preferably in a developing country, it would be of great
help to us. This leads us to our second issue: Are there other straw
bale projects happening in Ethiopia (or Africa) and how do we contact
them? Although my email account works well, Internet research
capabilities are poor, so that is not an ideal option.
If your organization has any information it can send to us it would be
greatly appreciated. There could be a significant impact on Ethiopian
housing if this project suceeds. Most importantly, my Ethiopian
co-workers are excited about this project. That makes me believe that
straw bales could have a long-term affect in this country.
Thank you for your time and we look forward to hearing from you in the
near future. If e-mail communication is possible, it would help
expedite this process.
Amhara Bureau of Works and Urban Development (BoWUD)
Bahir Dar, Ethiopia
[Text of proposal]
STRAW BALE MATERIAL RESEARCH PROJECT
One of the areas BoWUD focuses on is materials research. Not only do we
look at existing materials, but we also research new materials that are
beneficial to our communities. Straw is a material that has been in
existence a long time. Here in Amhara straw is commonly used in
combination with clay to make plaster for buildings. However, there is
another opportunity for using straw as a building material. Baled straw
is a building technology for load bearing and non-load bearing wall
construction (that is, it has the ability to support roof loads and it
can be used as a partition wall). This project will look at the
appropriateness of using straw bale wall construction in Amhara.
The most commonly used building materials in and around Bahir Dar are:
? Sheet metal roofing
? Grass or hatch roofing in the countryside
? Eucalyptus roof trusses
? Chipboard ceilings
? Concrete structural skeletons
? Concrete block in-fill walls
? "Chika" walls: eucalyptus with mud in-fill
? Cement or earth plaster
? Concrete and tile flooring
? Stone foundation
It is reasonable to assume that concrete block and "chika" walls take up
a significant amount of the materials and labor involved in the
construction of most buildings, in particular residential homes.
Substituting straw bales for concrete block and "chika" has the
possibility of reducing the amount of energy, materials, and labor
involved in a residential home.
Although cement is a necessary material in Ethiopia, it is only produced
in a limited number of locations and its production process causes
significant pollution - 8% of all carbon dioxide emissions comes from
the production of cement (Serious Straw Bale, 200, page 100). Cement use
can be limited by using concrete only for its structural capabilities
and not for non-load bearing walls.
In a similar fashion, eucalyptus wood is another material that is
necessary in Ethiopia. One concern is this wood is used for everything
from firewood to making ladders. There is no data available, but we can
assume Amhara is using up more wood than it is producing. Consequently,
it makes sense to limit as much as possible the amount of eucalyptus
used for in-fill walls ("chika" construction).
Straw bales are environmentally friendly and locally produced. Two other
such alternatives to concrete block and "chika" construction are rammed
earth and cement stabilized soil block construction. These are mentioned
because as the straw bale project moves along other possibilities in
construction materials might appear. There are many good construction
materials that could be beneficial to Amhara.
Without going into great detail about straw bales, here is a list of
some of the benefits of this material:
? locally and readily available
? provides extra income for the bale producer
? provides excellent thermal insulation
? provides excellent sound proofing
? provides an easy construction process
? stacking the bales themselves, owners can save anywhere from 5%-15% on
the construction costs
? when plastered, meets fire-resistant standards
? capable of having a life span over 100 years
The one major drawback to straw bales is that the straw itself cannot
get wet. If they do get wet, the straw bales will begin to decompose.
This concern is easily put aside with some good design principles,
including elevated footings, wide roof overhangs, and a good plaster
application. Straw bale construction does extremely well in dry hot
climates and not as well in consistently damp climates.
Straw bale construction has great potential in Ethiopia. What is lacking
is knowledge about this material and actual built straw bale structures.
Create interest in straw bale construction through research, design, and
presentation. Promote straw bales as an economical and sustainable
option for residential house construction in Amhara.
Scope of Work:
This project can be divided into six phases. Each phase is listed in
rough chronological order. The time needed for each phase is estimated
and any additional costs are listed.
1) Research costs, types, and availability of different straws in and
around Bahir Dar. This will involve driving to local farms and talking
to farmers. A car, a driver, and an Ethiopian counterpart who can
translate well will be needed to gain all necessary information.
Estimated time: 60 hours.
2) Research local plasters. Prepare a questionnaire, written in Amharic,
for distributors (storekeepers), contractors, and skilled laborers.
Earth and lime plasters are considered the best for straw bale
application. If water somehow gets into the bales, it needs to be able
to evaporate out through the plaster. So, good vapor diffusion in the
plaster is important. Earth and lime plasters have good vapor
permeability, whereas cement plaster has poor vapor permeability. Earth
plaster is nice because it easy to use, cheap, and it is familiar to
local laborers. One problem with earth plaster is it erodes easily. One
method involves using earth plaster as the exterior base coat and also
for the interior walls. The exterior finish coat is a lime plaster...
The project will include research on how the plasters can be colored.
What techniques are currently used and what makes the most sense for
straw bales. Estimated time: 60 hours.
3) A mechanical straw baler needs to be located. On very large farms,
straw is typically baled mechanically by large machines. In Addis, there
are bales of straw, but where or they were produced is unknown. The most
likely scenario is that there is no mechanical straw baler around Bahir
Dar. This will mean researching the best solution for producing straw
bales manually. The research team will need to produce a design of a
manual straw baler that can be constructed by a local craftsperson. Also
included in this phase will be research into the types, costs, and
availability of strings, wires, and/or straps needed to tie bales.
Estimated time: 300 hours. Additional costs: 1000 birr for constructing
a manual baler.
4) Prepare a report of construction methods that are most compatible
with straw bales. Included in this study will be different options of
installing electrical wires, plumbing lines, doors, and windows. The
research team will take a closer look at the benefits/limitations of
straw bale in-fill construction and of load-bearing straw bale
systems... Included in this phase should be some cost estimating for
various construction methods. Estimated time: 200 hours.
5) Contact various organizations that could be of help to our project.
We would look at organizations that could provide information regarding
straw bale construction in developing countries. Contact organizations
involved with funding overseas projects similar to this one. Communicate
with VSO regarding grants that might be available for this project.
Estimated time: 40 hours plus intermittent communication throughout the
6) Prepare and present workshops on straw bale construction.
Presentations will include an English/Amharic booklet with various
information and pertinent drawings. Workshops will provide a hands-on
experience of straw bale construction. The possibility of building part
of a small straw bale structure should be seriously considered. Each
workshop would last two or three full days. Estimated preparation time:
Total Estimated time: (not including time of counterpart or driver)
1) Research of straw 60 hours
2) Research of plaster 60 hours
3) Producing a straw baler 300 hours
4) Study of construction methods 200 hours
5) Contact organizations 40 hours
6) Prepare presentations 240 hours
Total 900 hours
Output of the Project:
At the end of this project, the following goals should be met:
? At least one Ethiopian BoWUD staff member will be very knowledgeable
of straw bale construction.
? Presentation materials will be created and accessible for future
? The knowledge of straw bale construction will be passed along to many
colleagues and community members.
? One manual straw baler will be designed and constructed.
? At least one small straw bale structure will be built.