by Athena and Bill Steen - Cohabitat

y Athena and Bill Steen
illustrations by
Andy Tannehill
a Canelo Project Booklet

CONTENTS
Introduction
Preparing the Base
Waterproofing and Drainage
Insulation
The Sub Floor
Finding a Soil Mix for the Finished Floor
Installing the Finished Floor
Method 1
Method!
Method 3
Dividing with a Wooden Grid
Stabilizing Earthen Floor Mixes
Surface Hardeners and Sealents
Floor Sealing Sequence
Maintenance and Repairs
Earthen Floors for Upper Stories
Taylor Publishing tms@northcoast.com
www.dirtcheapbuilder.com 707-441-1632
PO Box 375 Cutten CA 95534 USA

Earthen Floors
an introduction
Earthen floors are one of the oldest flooring method used
throughout the world in many climates and conditions. They
have ranged from basic dirt, hardened and "sealed" from years
of use, to elaborate clay mixtures poured in place, leveled,
and highly polished. Because of their natural warmth, softness,
and brcatliability, earthen floors make very comfortable living
surfaces.
Since local clay/soils can often be used and specialized
labor is not required, earthen floors can be inexpensive More
forgiving than brick, tile or concrete, they are easier to install,
or repair. Well built floors can be quite durable even under
high traffic. Once sealed, they can be swept, mopped or waxed
the same as other floors.
Earthen floors can be finished to look as one likes;
smooth and shiny or more "earthy" - slightly matted and
textured with flecks of straw. Wood can be placed into the
floor to create a grid-like pattern, or the surface can be scored
to look like tile. Different colored clays can be added to vary
the color. Earthen floors can also be used as sub-flooring for
coverings such as tile or carpet, and can be installed directly
over existing concrete slabs.
One of the most beautiful things about earthen floors, is
that there is no one way of constructing one. Formulas for
constructing earthen floors vary according to available
materials, cultural traditions, climatic conditions and
individual preferences. This booklet covens a few formulas
that we have worked with succesfully. With some
experimentation, testing and a basic understanding of the
general principles, it will be possible to create your own
earthen floor, that will be long-lasting, natural and beautiful.

Depending on site conditions, a well constructed
earthen floor may consist of several layers.
Preparing the Base
To help prevent the floor from cracking or settling, the ground
should be well compacted an free of all movement All organic and
plant matter should be removed. If very expansive clay is present, it
should be removed and replaced with another non-expansive soil or
other substitute. The ground should also be dry before beginning
construction of the floor
Waterproofing and drainage
If the capillary rise of moisture is a problem, steps need to be
taken to improve drainage and stop the upward movement of moisture.
For many situations, a layer of 6 to 12 inches (15 to 25 cm), of either
dry stone topped with gravel, gravel, or coarse sand may be adequate
to improve drainage and stop moisture migration. Certain volcanic
stones like pumice could also provide the additional benefit of
insulation as well as protection from moisture. The uppermost portion
can be comprised of finer gravel or coarse sand to prevent the upper
layers of the floor from falling through.
If more drastic measures are required, plastic or petroleum based
membranes can be laid down, to prevent capillary rise, but at the cost
of losing the b readability ofthe floor and contact with the earth itself
Preferably, this membrane should be laid with care on top of a layer
of sand to avoid any tears or punctures.
If a non-synthetic, water-tight barrier is desired, a thin layer
( 1/4" to 3") of soil with a high clay content or bentonite can be used.
It can be applied in a moist state in several layers, filling all cracks as
each layer dries. Troweling each layer will help compact the clay
mix and reduce the pore space. This will further aid in creating a
water-tight seal. The top layer in particular needs to be wellcompacted.
Bentonite sheets (1/4 H
thick, backed with cardboard), can
also be purchased, although more costly. (See resources.)
It might be possible that the application of a lime plaster which has
been stabilized with a water-resistant material, like prickly pear cactus
gel, could be effective as an anti-capillary barrier Whatever approach
is used, it should be tested first to determine if it performs well.

Insulation
For insulation, 4 to 6 inches (10 to 15 cm) of straw/light-clay
(see formula below), perlite/clay, pumice fines, or expanded day (clay
that has been heated, expanded and filled with small air spaces) are
some of the natural options that can be laid on top of the gravel or
drainage layer. If desired, one can always resort to rigid foam
insulation.
Clay Slip
A clay slip acts as the "glue" that binds together the straw or the
perlite in straw/light-clay or perlite/clay mixes. A soil with very high
clay content can be passed through a 1/8" screen to remove small
stones and other debris. It is then mixed with enough water until it
has a consistency of a latex paint. When a finger is dipped into the
mixture, a coating should remain that obscures one's finger prints.
Straw/light-clay
Gay slip is slowly poured onto a small quantity of loose straw
(2-3 flakes) at a time, then mixed either by hand or with pitchforks,
until each straw is coated with clay slip, similar to tossing a giant
salad, when the straw sticks together in a bundle when tightly
squeezed, the mix is ready. To keep the mixture from drying out while
more is being made, it can be stored under a tarp. If allowed to sit for
a couple of days, the mixture matures and improves.
The straw/light-clay needs to be tamped such that poorly
integrated layers are not created. The butt end of a 2x4 works to tamp
and work the mix together. Upon completion, the straw/light-clay
needs to be solid and not spongy. J
*A solid and compact layer of straw/light clay requires practice and
can be somewhat labor intensive.
Mixing Straw/Light Clay

Perlite (or vermiculite)/light clay
Perlite is mixed with a clay slip, either by hand or with a concrete
or mortar mixer. Enough slip needs to be added so that the perlite
binds together and that the mix has sufficient density. Like most facets
of the earthen floor making process, experimentation will be needed
to yield the proper proportions.
Pumice fines (or other lightweight volcanic stone) can most
likely be laid dry and tamped for good compaction.
The Sub-Floor
The finished earthen floor, needs to rest on a compact, level
surface. If an insulating and/or drainage layer has not been used, the
sub-floor can be nothing more than the well-compacted ground.
Otherwise, 2 to 3 inches of compacted silty/sandy soil (not pure sand)
can be applied over the insulating or drainage layer to insure a solid
base. This soil needs to have enough day that it holds together when
dry. Slightly moistening the soil will help the initial compaction. The
sub-floor can serve as a good working surface during the final
construction stages of the building. Foot traffic will help compact
the bottom layers.
Radiant floor tubing can be installed into this sub-floor layer.
Finding a Soil Mix for the Finished Floor Layer
Determining a good soil mixture, a combination of clay, sand
and fiber (chopped straw), is the most critical step of the finished
floor layer. The mixture needs to have sufficient clay to bind all the
ingredients together with good strength. Conducting a series of tests
using varying proportions of these ingredients, is a crucial step. The
strongest earthen floor is one that doesn't crack. Cracks, even when
filled or grouted remain the weakest and most vulnerable part of the
floor to damage. Creating test samples to see how they dry is crucial.
Analyzing soil for clay content
To determine whether or not soils contain enough clay to be
used for a floor, several simple tests can be done. One is to form the
moistened soil into a round egg-sized ball using just enough water to
bind it together without it sticking to the hands. Let it drop. If it breaks
easily there is most likely not enough clay content. If it resists breaking
and has a sticky adhesive quality, the clay content is probably
sufficient. The same ball can also be cut in half with a knife. A shiny
surface on the soil reveals clay while a dull surface indicates silt
Another indicator is that clayey soils resist penetration of a knife
while silty/sandy soils show little resistance. Handling and feeling
different soils and noting the differences between them will begin to
reveal a lot about them. With a little experience you will have a
natural sense about what generally needs to be added to correctly
adjust the soil.

Mixing Test Samples for Finished Floor
To find a mix for the finished floor, the soil being used needs to be
tested first alone and then sit h varying quantities of sand and/or straw.
Both the soil as well as the sand should be sifted through 3/8 inch
hardware doth to remove any larger particles, debris and stones. Mix
enough material to create test samples that are approximately 1/2 to
1" thick and 12* square
Clay soil by itself
Mix with water without sand or straw
Clay soil and sand
Dry mix different proportions of soil and sand
Add increments of sand:
1/2 part sand to 1 part clay/soil
1 part sand to 1 part day/soil, etc.
Continue up to 3 parts for starters.
Add enough water to thoroughly blend alt the ingredients. The
mix should be kept as dry as possible and yet remain workable.
These samples should dry in the same place where the finished
floor will be installed. Make sure the samples are marked with
their appropriate percentage of clay and sand. When dry,
choose the sample that has no cracking and has sufficient
strength. Too much sand will produce a weak floor. If by
chance, none of the samples are free of cracks, the soil being
used may be unsatisfactory because of the expansive nature of
the clay.
If the crack-free sample lacks adequate strength, it is then
necessary to work backwards. Select several of the samples
that seem to have good strength and start over by remixing
them but this time with straw. Begin by adding 5% and continue
in increments of 5% up to 25%. When dry, observe to see if
there are any samples that are crack-free and that have good
strength and density. Too much strew may yield samples that
lack sufficient density for a good floor The straw used should
be finely chopped (straw passed through a 1/4" or 1/8* screen).
Clay soil with straw
Another option is to mix the clay soil with only straw and
no sand. In this case the concentration of straw will need to be
higher than if sand were added. As above, add straw in
increasing increments, 5% at a time This approach has value
when sand is difficult to come by or is an added expense when
money is scarce. With such a high quantity of straw added,
there may be more difficulty achieving enough compaction and
strength.
Sanely soils
There are some soils that are too sandy or silty by nature and
lack sufficient clay to produce a good floor mix. There are basically
two major options in this case. Either additional clay can be added
to bring it up to a suitable level or a small amount of portland
cement (6 to 10%) can be added. Cement is probably the most
commonly available stabilizer for sandy soils.
Straw can also be added for effect, if wanted, to any test sample
that produced good results without it.
Once a mix has been selected, a larger test sample (a square meter)
can be completed for final confirmation.

We have included three different methods for installing earthenfloors,
lire steps which have been covered prior to this point are the same
for each method unless stated otherwise.
Method 1 is a troweledfloor that is both durable and beautiful, but
is the most labor intensive of the three methods. It is our choice for
areas that receive the most traffic and where an attractive floor is
desired
Method 2 is a tamped floor that is of lower quality than method 1,
but isfaster to install. It would be a good choicefor areas with less
traffic or where the finished look is not as important It wotild also
be a good choice when using an earthen floor as a base for tile,
carpeting, etc.
Method 3 is the easiest andfastest of the three methods, but the most
experimental and the one for which we have the least amount of data.
It is simply installed dry and moistened in place using psyllium seed
as a stabilizer. We have created some incredible samples using this
method, but consistent results will require more work and
experimentation.
Method 1
This version produces the most finely finished and durable earthen
floor that we have seen.
If the base for the floor has been properly prepared, the thickness
of the finished floor can be thin, anywhere from 1 to 2 inches.
Historically, earthen floors have often been treated like concrete pours
and have been installed at a thickness of 4 inches or more, but this
excessive thickness can make the floor much more susceptible to
cracking and substantially increase the drying time.
Typically, we have had good results with a 1" finished floor
layer, applied in two seperate 1/2" thick applications. It is conceivable
that it could also be done in one layer, although there would be more
shrinkage and cracking problems. Three layers might be necessary, if
problems have developed as the floor is being installed.
Getting ready to begin.
Before beginning, the height of the various floor layers need to
be marked on the walls of the room. For example, if two 1/2" layers
are being used, a mark 1/2" above the top of the sub-floor, along with
another at 1", need to be made. These marks can then be connected
by drawing level lines between them, or snapping a chalk line. A
water-tube level in combination with a Standard carpenter's level are
usually adequate for most rooms, however a transit could be helpful
for larger rooms.
Prepare your tested floor mixture, measuring the ingredients
carefully, so that each batch is consistent. Thoroughly dry mix. It is a
good idea to save and store some of this dry-mix for future repairs.
Just enough water should be added to make the mix workable. The
drier the mix, the less the floor will shrink and crack. Straw added to
the first layer will help control shrinkage. The base needs to be
thoroughly clean (a vacuum works well for this), and dampened before
applying the floor mixture.

Applying the floor mixture is most easily done with a trowel
Swimming pool trowels have rounded corners and are easier to use
with earthen materials. Standard square cornered trowels have a
tendency to leave marks and are harder to control A 3" to 4" putty
knife can help when it is necessary to work corners. Longer, concrete
floor trowels, also work well and help to level larger areas of the
floor.
It is usually easier to apply the floor mixture in 2 foot wide strips
across the room. When finishing each strip, it is extremely important
that the edges of each of these sections be tapered or beveled and
then scored or scratched. In this way the following section will overlap
and integrate well with the previous one. Failure to taper each section
at the edge will typically produce cracks wherever sections meet.
The base needs to be kept damp, especially the area where the
mix is being applied. This keeps the base from wicking water too
quickly out of the floor mixture, and thus producing cracks.
It is best to do an entire room at one time. However, if it is a
large room, or time does not permit it is possible to stop and resume
later, as long as the tapered edge of the last section is well moistened
before continuing
Where the earthen floor meets a wall, a door sill, or any different
type of material, such as brick, concrete or wood, a 1/2" strip of drier
mix, should be used to minimize shrinkage. Some dry mix can simply
be added to what has been already mixed for the rest of the floor
Keeping the floor level as you go.
There are a variety of techniques that can be used to keep the
floor level while each application is being made.
To check the level and to remove any excess material or
unevenness a 3 foot level is handy. It can be attached or taped to a
length of milled lumber of the same or slightly longer length, to drag
across sections that have been installed.

As guides or reference points while troweling the earthen
mixture! sections of re-bar or pieces of wood (the same dimension as
the depth of the application) laid at periodic intervals across the base
layer. For example, if each layer is one half inch thick, a piece of #4
re-bar can be used as a guide to regulate depth. As each section of
floor is completed, the re-bar or wooden guides can be removed and
repositioned for the next section. Make sure to carefully fill the gaps
left after removing the guides.
When a room is large, it can be difficult to maintain a level surface
when installing the floor. One remedy is to use pre-laid, 3 4" strips
of floor mix at approximately 6 1
intervals, to create reference points
for the correct height of the floor. Once in place they can also be used
to lay a board or level across and adjust the height of the floor.
The first layer of earthen mix can be left slightly rough so that
the second layer will better adhere to it. There is a point when the
floor will be dry enough to walk across -yet still damp enough to be
workable. At this time, any cracks or shrinkage lines that have
occurred, can be worked with a trowel. This first layer can be left
fairly rough for the next layer to adhere to. To help spread the
concentrated loads of feet and knees, so that no marks or depressions
will be left on the floor surface, two pieces of plywood or some other
flat, rigid material can be alternately leap-froged across to create a
path of movement.

The second layer
Optimally; the second earthen floor layer should be applied
while the first layer is still damp, yet leather-hard. If the first layer
dries out before applying the second layer, be sure to dampen it well
before starting, and while working. If for any reason, the first layer
showed any cracking, adjust the soil mixture and retest before applying
the second layer
The second layer of the earthen floor is applied in exactly the
same manner as the first. Once the floor has hardened, but is still
damp, it can be troweled, using a little water, to give a smooth, fine
polish. A spray bottle works well to apply the water. Wiping the floor
lightly with a wet sponge and troweling it will bring out the flecks of
straw.
Depending on the weather, the entire floor could dry in as short
of time as a few days in drier climates or as much as several weeks in
damper conditions. A fan could help speed up the drying process.
AD traffic should be kept off the floor during this time.
Method2
This method produces a floor that is not as durable as
Method /, but is easier to install.
The technique
It is possible to construct an earthen floor by tamping
or ramming. It can also be done in multiple layers, but at greater
thickness because it is done with a dry or slightly moistened
mixture rather than one which is wet enough to trowel. The
Initial layers of this floor need not be as finely screened as for
Method 1. Soil passed through a 1/2 inch screen is more than
satisfactory. Select a clay/sand mix as described earlier in the
text. Prepared road base has also been used with good results.
Each layer can be somewhere between 1.5 to 2 inches
in depth with the total depth of the floor at 4 to 6 inches or
more if conditions require it.
Adding water
The first layer can be applied dry and then moistened
slightly with a mister on a hose or a watering can. The soil
mixture should be wet enough that the clay can bind the
ingredients together, but not so wet that it can't be walked
upon without disturbing it. The mixture can also be lightly
moistened before applying. Doing so helps ensure that the
moisture is evenly distributed throughout the mix, but it is
more laborious.
Another option, which will help further stabilize the
soil, is to add boiled linseed oil to the water at a rate of 4
liters of boiled linseed oil, diluted with 2 liters of water for every
100 liters of soil (by volume).
Tamping
The mixture can then be roughly
leveled and then compacted with a plate
compactor. Hand tamping is clearly the
least expensive, but more laborious.
Simple tampers can be made from
plywood with a handle or metal plates
welded to a piece of pipe. Mechanical
plate compactors are commonly
available through tool rental outlets.
When using one, it is necessary to handtamp
the edges of the room where the
floor meets the walls.

Additional layers
When this first layer is completed, it can be followed with other
layer or layers. If the finished look of the floor is not so critical, this
can be the final layer. More care can be taken to level the surface.
Dragging a board across the surface to screed it as done with concrete
is a good method
Tamping will produce edges, but these can be smoothed or
softened with a trowel and retamped to create a reasonably level
surface If this is the final layer, it should be applied slightly higher
than the intended height of the floor as tamping will compact the
floor mixture approximately 20 to 30%.
Final layer
If the surface of the final layer is not smooth enough, it can be
topped with a very thin troweled-on application of the same soil
mixture, screened with 1/8* hardware cloth. It is applied in the same
way that one would apply a finish plaster to a wall. Care should be
taken to make sure that the previous layer is well moistened to ensure
a good bond between the two.
A hybrid version of Method 1 and 2 can also be used for the
final layer. A1/2 inch layer of a clay/soil mix, as in Method 1, can be
troweled on top of the tamped layers.
Method 3
This is the fastest method of the three, but less finished with more
texture than methods 1 and 2. It is also suitable for outdoor surfaces
in dry climates.
Soil Mixture
This method uses psyllium seed as a stabilizer in combination
with a sandy soil mix or another material that has a fair amount of
aggregate. Psyllium acts like clay or cement, it coats small pieces of
aggregate and triads them together, ft is often used with crushed granite
for outdoor walkways.
Ground psyllium seed (see resource section) is dry mixed at
the rate of 1 lb. per 10 square feet to create a 2 inch thick floor. For a
3 inch thick floor, 1 lb. per 7 square feet is needed. A mortar mixer or
concrete mixer is good for larger quantities.
Application
This mix is spread dry over the base layer that has been soaked
with water. It is then leveled and compacted with a roller, as is typically
used for landscaping.
The soil and psyllium mix is then saturated with water by using
a spray nozzle that has a mist option. Applying the water in a mist
does not disturb the prepared surface of the floor. It is essential to
moisten the soil mixture so that the full depth of the material receives
water. After the surface water disappears, the surface can be further
compacted with a roller.
The top layer can be troweled lightly to help seal the surface of
the floor and to produce a smooth surface. Too much pressure will
tend to float the psyllium to the top and weaken the bottom layers.
The surface can be misted or moistened slightly to facilitate the
process.
It is possible to apply the psyllium in a wet mix with a trowel,
like in method 1, but it can be difficult to control the consistency of
the soil psyllium mix. Which has a tendency to continue absorbing
moisture and consequently continues becoming drier and changing
in consistency. However, some experimentation may yield good
results. Small samples that we have created using this method have
yielded good results.
Volume of soil needed for the finished floor layer
At adepth of 1 inch, approximately 1 ton of soil mixture will be
needed for every 200 square feet; for 2 inches, 1 ton per 200 square
feet is needed; for 3 inches, 1 ton per 65 square feet.

Earthen floors can be divided with grids of wood, brick, concrete
QT other materials If wishing to do this, it is important to remember
that earthen doors are strongest to a monolithic form without any
divisions Their weakest point is at the edges and when divided by
other materials, the number of edges increases considerably. Dividing
the floor into sections does make it easier to level Smaller tile-sized
sections can also be made and then grouted with a different colored
clay
Stabilizing Earthen Floor Mixes
Most soil mixes will make a good floor without additional
stabilization. They can be added if additional hardness is required or
if the soil mix doesn't produce enough binding and strength. Choice
of stabilizers can vary depending upon available resources.
An easy and inexpensive stabilizer that was sometimes used
throughout the southwestern United States was wheat flour paste
Wheat flour paste can be made from commonly available white flour
mixed in the following manner
Mix 1 cup of white wheat flour with I pint of water and add
it to 2 cups of boiling water. Then cook at low heat until it becomes
slightly translucent taking care that the mixture does not stick and
burn Dilute this with 2 quarts of cold water and use it as the water to
mix the soil ingredients.
Another option is using casein powder which produces a natural
glue. It is prepared by soaking 25 grams of casein powder and 8 grams
of borax in enough water to form a putty. The putty can then be diluted
with water to a consistency suitable for mixing the soil ingredients
Auro (see resources) makes a powdered casein glue that could also
be used Synthetic polymer based glues like Elmers or Concrete
Bonder can be used at a ratio of 16 ounces to 22 shovels of mix.
Surface Hardeners and Sealents
To be effective, a good sealant needs to penetrate deeply into the
earthen floor rather than form a skin or shell on the surface of the
floor, as do acrylic sealants. The problem with skins, is that they
create a thin, hard cap on top of a relatively soft material (the earthen
floor). This cap or skin is then susceptible to damage and when it is
broken, produces "pot holes" in the floor.
Traditionally, the most successful sealents have included oils,
animal urine and bloods. Penetrating oils, which oxidize and become
fixed, are often the best choice for earthen floors, as they not only
seal, but harden the floor as well. Unseed oil is probably the most
cost effective and widely available of these oils. However, other
options include hemp oil, castor oil and possibly, cottonseed, coconut,
and fish oils. Boiled oils are preferred, because they require much
less time to dry. Another option which we have not tried, but that
could be superior to any of the above is stand oil. Stand oil is usually
linseed or tung oil which has been exposed to oxygen in order to
oxidize it In former times, oils were left to stand exposed to the
oxygen in the air tQ produce the same effect and dais the name, stand
oil, however stand oils can now be produced by injecting oxygen
into the oil

There are a number of varnish combinations which are
manufactured in Europe that are composed of varying combinations
of linseed oil, tung oils, solvents, dryers and other substances that
could also be effective, particularly for the final coat. A source for
these products is Sinan (see resources) which is a representative for a
European company named Auro which manufactures a complete line
of natural paints, oils, solvents and related products. Their linseed oil
is organically grown and not diluted with any type of petroleum
solvent
A solvent for thinning the oil will also be necessary. There a
number of options which include everything from common mineral
spirits and turpentine to more expensive environmentally friendly
thinners diluted with citrus oils, ordorless turpentine and pure citrus
oils. Unfortunately almost all of the natural oils and solvents are
considerably more expensive.
Oils penetrate deeper and more effectively when they are heated,
and will also be more readily absorbed, if the surface of the floor and
the room are warm.
// is extremely important to remember that both oils and solvents
are very volatile and flammable and need to be treated with great
caution when heating. Any brushes and equipment used during the
application are also subject to spontaneous combustion after they
have been used and should be carefully stored in closed containers
Generally, it is better to apply the oil in a stronger concentration
in the initial coats, gradually reducing the percentage of oil to solvent
in the following coats. The earthen floor is less porous with each
subsequent coat of sealant, and will accept full strength oil more
readily at the beginning. Our best results have come from applying
full strength oil for the first coat, gradually diluting it in several
subsequent coats.
Floor Sealing Sequence
The floor should be completely dry before sealing. The oil/
solvents to be most effective should be heated, but only with the
utmost caution. They should be warmed, but not taken to the point
where they began to smoke.
Each coat should be applied only to the point that the floor can
accept the quantity being applied and no more. If it starts to puddle,
the oil/solvent combination may form a cap on the surface of the
floor. A large brush can be used to apply the oil. Remove excess oil.
Coat 1 - Apply full strength oil
Coat 2- Dilute the oil with 25% solvent
Coat 3- Dilute with 50% solvent
Coat 4- Dilute with 75% solvent
Subsequent coats should be applied as soon as the previous one
is fully absorbed and no longer tacky to the touch. With 4 coats, the
floor should be sufficiently sealed, yet if more sheen is wanted,
additional applications of "Coat 4" can be added.
Some of the above mentioned varnish preparations might be
effective as a final coat. Since no specific testing has been conducted
on earthen floors, small samples should be experimented with before
attempting an entire floor. Watch that an impermeable cap or skin on
the floor is not created. Besides stand oils and linseed oil varnish,
Auro manufactures a product called Natural Resin Floor Sealer that
is a combination of different stand oils, solvents, and dryers that could
be very effective. They also have another product called Clear Amber
Varnish which is also a combination of stand oils and solvents, but
also includes colophon amber which gives a harder finish.

Periodic Applications of Coat 4" can be used at maitenance
coats The frequency of this application will depend upon the amount
of wear the floor receives For an average floor, somewhere between
6 months to a year is sufficient. Although, if a high sheen is not
important, the Boor can go years without the addition of any further
coats or maintenance The application of a hard wax can also be used
Recipe for hard wax: 250 kg's of camuba wax, 250 kg's of beeswax
and 5 kg's of turpentine or other solvent, all dissolved together in a
double boiler
Auro produces two different floor wax products that could be
used for floor maintenance Beeswax floor care is designed for regular
floor care and produces a water-repellent coating while Floor and
Furniture Plant Wax contains carnauba wax and gives a harder finish.
Repairs
If the floor needs repair, open up the crack or hole, splaying
the edges, so that the hole or crack is smaller at the top than at the
bottom. If the crack or hole is small, it can help to pass the mix through
window screen to remove any large particles and debris. Thoroughly
moisten the floor when applying the new mix. Seal when dry.
There is a variety of reinforced and/or stabilized load-bearing
earth and earth/straw in-fills that can be used between floor joists to
provide a satisfactory base for an upper-level earthen floor.
It is important to establish a solid enough base that doesn't move
(so uncharactenstiocharacteristic of many wooden floors). Another
consideration is that an upper-story earthen floor will most likely be
quite heavy and the calculated loads must be within the limits of the
structure Reducing the span between floor joists can help distribute
loads along the walls, but also improve the performance of the in-fill
material
Light clay/straw is possibly the best in-fill, in that it is lighter
than solid earth, a good insulator and has good tensile, shear and
bending strength.
The light day/straw mix can either be packed directly between
the floor joists or beams, or can be made into prefabricated panels or
blocks, and positioned once dry. Some type of horizontal reinforcing
element, such as; lx2's, 1/2" re-bar, 1" bamboo, willow branches, or
some other type of branch, spaced every few inches, needs to be
integrated into the light clay/straw in order to make it load-bearing in
a flat position. These reinforcing elements need to be strong enough
to carry the loads imposed on them from above as well as the weight
of the infill material itself.
Once the infill portion has been completed and is thoroughly
dry, a 1 inch thick (two 1/2 inch layers) section of earthen floor can
be installed, as described earlier in the text If the floor joists are to
be exposed, the infill material should stop 1 inch below their top, and
if they are to be covered, the infill material should cover them with at
least 2 inches of material. Burlap, coated with a clay slip can be placed
on top of the straw/light day if further protection from cracking is
desired. Any of the light day/straw infills can then be plastered
underneath, on the ceiling side.

Obviously the construction of an upper-story floor in terms of the
actual construction and the calculation of loads, etc. is more complicated
them can be dealt with in a small booklet like this, but we have included
short descriptions of the basic techniques to give the reader some idea of
how these infill sections are constructed. The relationship between the load
of the light clay/straw to the joists and walls as well as the technique for
constructing the in fill, needs to be thoroughly understood before attempting
this type of construction.
Light clay/straw infill
A mixture of light clay/straw can be tamped directly into place,
using a slip-form attached to the bottom of the joists or rafters thus
producing a flat surface when the form work is removed The
reinforcement rods, placed every 2-4 inches, rest on the ledgers which
are attached to the lower sides of the joists.
These infill sections can also be curved by using a form work
of flexible branches such as willow which are bent to the desired arc
and placed 1 or 2 inches apart The light clay/straw is then packed on
top of them.
Prefabricated blocks of straw/light-clay
T-shaped straw/light-clay blocks can be prefabricated to rest
between the rafters or floor joists. Two reinforcing rods are worked
into the middle of the block when packing the wet mix into the form.
The blocks can be removed immediately from the form and set aside
to dry. A little clay slip can be used between the blocks as mortar,
when the dried blocks are laid in place. The blocks can be shaped to
produce either a flat or vaulted ceiling.
Light clay/straw ceiling rolls
Another version of creating a flat infill section, is to use reels
made up of a fibrous material, like straw or grass, coated with clay
slip and then wrapped around reinforcing rods. These reels are slid
between the joists, compactly against each other while still wet. As
with the other infill methods, the bottom of the rolls can then be
plastered.

Yavapai Sports Surfaces
P.O. BOx 17150 r
Ft. McDowell, AZ 8S264
(602)837-8038 $
1-80O-9-2724
Psyllium seed
Sinan Company
P.O. Box 857
Davis, CA 95617-3104
(916)75-3104
Auro products-natural paints, oils solvents,
waxes, etc
The Pilot Chemical Co.
1030 Jackson Ave.
Long Island, NY 11101
(718)729-8282
Casein powder
Frank Andreson
Duseldorf, Germany
summer address:
P.O. Box 249
Brownfield ME 04010
We have worked with Frank Andreson of
Germany who Is skilled with many years*
experience In building with light
Wc ait a small non-profit organization dedicated to connecting people,
different cultures and nature. Our work explores living, building and food
production practices that can be simultaneously beautiful and sustainable
The Canelo Project is defined by the place we call home - a 41 acre
secluded homestead tucked into the higher elevation oak woodlands of
southeastern Arizona. Shaped and nurtured over the last eight years, the
site provides a comfortable and peaceful context for learning, applied
research, and cultural exchanges.
Our current projects include:
• Workshops and Tours
Ongoing programs focusing on natural building, straw bale
construction and the living arts.
• Straw-Earthen Housing in Mexico
Innovative low-cost housing using local and natural resources.
• Enjarradora Program
Training women and children In the traditional livelihood
of working and building with earth.
• International Exchange
Bringing together people from around the world, to share
their specialized skills and cultural knowledge.
We invite you to join us and participate in any of our ongoing activities.
We welcome your interest and support. If you would like more information
about the Canelo Project, workshops, and other mail order products, or for
more copies of "Earthen Floors*' ($8.50 + $1.50 shipping)
Call or write to:
THE CANELO PROJECT
Athena and BIO Steen
HC1 Box 324
Elgin, AZ 85611
(520) 455-5548
fex(520) 455-9360
absteen@dakotacom.net
all donations are tax-exempt

When I was a boy, my father was the main one to look after the
church. Once when we had been up to southern Colorado to visit part
of our familyfor a couple of weeks, it had been raining here almost
every day we were gone, heavy rains. The day after we got back, my
father took me with him to go see how Aings were with the church.
We could see as soon as we walked up to the church how heavy the
rains had been. The adobe plaster was washed away here and there,
and the winds had blown a cottonwood limb onto the roof When we
went to open the doors, the wood was so swollen by the water that we
could barely open them.
When we got them open and saw inside, we just stood there awhile not
saying anything* There, growing out of the adobe floor, was a young
stand of wheat
I remember trying to convince my father to leave the wheat alone-it
seemed right to me that it should be there-but he Just smiled and said,
"Ml hijo, you know we can H worship the wheat n
lna couple of days,
everything was back to the way it was, but I never forgot that day.
Elder from northern New Mexico village.
Persistence of Memory \ New Mexico's Churches
Museum of New Mexico Press