Tire - House Builders: No More Pounding!
What's new in tire - house building? Tire Bales!
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What Are Tire Bales?
Tire-bales are "big rubber bricks". Place them in the wall with a large fork-lift, a hay-grapple, larger size skid-steer w/forks (3,000# tipping weight, minimum), or a backhoe. They're made in a hydraulic press, exerting extreme forces to compress approximately 100 tires into a "brick" 2-1/2' x 5' x 4-1/2', weighing ~2,000#, wrapped with (5) .113" diameter steel wires pre-formed into square-knot ends which are hooked together when the press reaches it's compression capacity. The press is then released and the bale is completed. The bale is now the density of packed earth, weighing in at roughly 90 pounds per cubic foot and containing only 5% air.
For information on
tire baling machines, see either the Eagle
Enviro-block tire baler or the
Encore Systems, Inc.
machine. As I have no connection with either manufacturer, please
contact them separately. If you are interested in using tire bales for
your future residence, contact them both, give them your location and ask for
any knowledge of the nearest baling machines to your future building location.
Keep in mind that these machines are portable, making tire bales like gold, i.e.
where you find them. You might also contact any local tire dumps/recyclers
to see if they have knowledge of tire bales local to you.
Sedalia, CO Supplier of Tire Bales Because
of the enormous square footage of bearing surface for each running foot of
framed wall created by a tire bale wall (5 square feet/running foot), no reinforced concrete
foundation is necessary except where tire bales aren't used. All that is
required is that the topsoil and any organic matter be removed from the leveled
grade before placing the bales on the earth. To start
with the most often voiced concern; that the bale will deflect when used as a
structural element, much like any other piece of rubber. This is true, they will
deflect, and the
tests have proven it so. However, they have been "deflected"
considerably to become "bales" in the first place, and the load required to
deflect them further is acceptable (more than your
house will ever weigh), and is roughly 1/20 of what has been called a "failure" (150,000#
on an unsupported bale; usually when a wire breaks). In other words, your house will NEVER exert that much load on a
tire bale wall used as a foundation wall. Also, a steel reinforced
concrete bond beam is poured in-place on top of the
tire bale wall, to distribute load of the roof framing and possible loads placed
on the roof. What's more,
all tests (to my knowledge) have been run in the single-bale
or single-stack of bales mode. These tests (and results) do not reflect
the true usage/deflection of the bale in practice (constrained by other bales in
the wall).
Numerous independent tests have been run to determine the ultimate deflection
characteristics of the bales and none has been found. In other words,
there is no significant failure mechanism of the tire bale, regardless of pressure. It
just keeps deflecting, the more load is applied (tests being conducted in the
free, single-bale state). In the restrained state, as in a wall or stack,
as shown at left, it would be significantly more pressure resistant, beginning to
resemble a 'hydraulic' resistance. Here,
an explanation is given for results of a study of tire bale insulation: "The Colorado School of Mines study that we
have discussed predicts that the thermal conductivity (U) of tire bales
can range from: 0.120 - 0.124 Btu / hr ºF ft Which converts to an R-value range of 0.694
- 0.672 per inch, or a total R-value of 40.0 - 41.6 for a 60" tire bale wall.
This is a far cry from the undocumented claims of R-120 for the same thickness,
but it would nevertheless equate to approximately 11.75 inches of fiberglass batt insulation - about what you could put into a 12" thick stud wall... which
is about 3x as much insulation as goes into a standard 4" stud wall...very good
wall insulation by conventional standards. This material should yield
super-insulation-like performance if the entire wall is assembled and completed
properly from interior to exterior... Moreover, the tire bales also have a
predicted Specific Heat (Heat Capacity) of 0.18 Btu / lb ºF. This compares
favorably with other common thermal mass materials like sand (0.20), stone
(0.20), and concrete (0.15). So, the heat storage capacity of the tire bales in
a passive solar house should be excellent as well. For the house Mikey
mentioned in a recent e-mail, the tire bales alone - at a 10ºF temperature drop
should have a storage capacity of: 130 bales * 1T/bale * 2000 lbs/T * 10
degF * 0.18 = 468,000 Btu Nearly half a million BTUs is a
considerable amount of heat! The interior plaster will add even more heat
storage... So - perhaps it is possible to have one's (thermal) cake and eat it,
too...!! The tire bales should provide excellent insulation - and - provide
good heat storage as well. The price one must pay for this, of course, is the
massive thickness and weight of the tire bale wall."
For more information (118K
.PDF file) on residential building with tire bales see this paper:
"Building
With Tire Bales - Addressing Some Engineering Concerns"
by Leonard Jones, P.E. RIP
Also of note, the material of the tire bale, primarily manufactured rubber (with
small amounts of steel, i.e. steel radial belts), is listed as exactly the same
specific gravity (1.52) and density (95 pounds/cubic foot) as packed
earth. See:
this document for confirmation.
The bales contain less than 5% air.
Beyond that, there are some limitations to the use
of tire bale walls in residential construction, as I see them: Once you get past these, there is NOT a better, less expensive, eco-friendly way to build a 5' thick wall!
Tire-Bale Gallery
Great Tire Bale House Resources 
The Original Tire Bale House 
Tire-Bale Construction Sequence 
A Happy Tire Bale House Builder 
A Beautiful Tire-Bale Home |
The picture at the
left illustrates in a rather low-tech way, that the bale is VERY sturdy.
Note: a stack of bales, ten high, covered by local earth distributed by a
70,000# front-end loader. The bottom bales show no apparent compression or
effect of bearing that load. I've measured them and there is
little (1/2" or so), if any measurable difference between the bales at the top of the
stack and those at the bottom. This being under a load of more than 9 tons each
(bales constrained by stacking immediately adjacent to each other, as in a wall.
The bale at the bottom is bearing more than 720#psf with little measurable deflection.
Testimony
" Mike Shealy was of great help in the design and completion of our earth/tire house. We had many questions as our project progressed and Mike was always available to answer them and share new ideas. We highly recommend his many talents and patient assistance."
by: Laura & Santi, Home Owners
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About Michael Shealy
As an Architectural Designer, Michael provides residential designs using hybridized practical building techniques. These methods are beneficial to the Earth and the end user, employing used tires that are a highly durable, easily obtainable/free building material that removes problem waste from the eco-cycle.