Papercrete
Encyclopedia
Papercrete is a recently developed construction material which consists of re-pulped paper fiber
with Portland cement
or clay
and/or other soil added. First patented in 1928, it has been revived since the 1980s. Although perceived as an environmentally friendly material due to the significant recycled content, this is offset by the presence of cement. The material lacks standardisation, and proper use therefore requires care and experience. Eric Patterson and Mike McCain, who have been ascribed with independently "inventing" papercrete (they called it "padobe" and "fibrous cement"), have both contributed considerably to research into machinery to make it and ways of using it for building.
, junk mail
, magazine
s, book
s, etc. obtained from the local dump or from waste bins are all useful. Depending on the type of mixer used to pulp the mix, the paper may be soaked in water beforehand.
A typical homemade mixer uses a small electric motor
mounted directly on a shaft with two four-inch square blades attached, resembling milk shake maker. This shaft is suspended in a plastic 55 gallon drum to mix the material.
Another homemade mixer is made from a trailer built from the rear end of a car, with the differential input pointed upward and a lawn mower blade attached. When the trailer's wheels turn, the differential gears spin and power the blades. The blade is placed in a large stock watering tank to mix the material. A baffle on the side of the tank forces the slurry back into the blade as it circulates. With this mixer it has been possible to make three or four wheelbarrows full of thick papercrete in about twenty minutes.
Paperpulp may be added to clay soils where sand is not available. The added paperpulp helps to minimize cracking when the material dries.
. This limits its range of use within the city limits of most incorporated United States
cities where building codes apply. It is not used as a load-bearing wall where building codes apply. However, its strength in model structures has been proven, and homes and small commercial buildings are being constructed. There is little or no evidence of its long-term durability at present.
In these small building projects, papercrete is being used as an in-fill wall
in conjunction with structural steel
beams
or other load-bearing elements.
Papercrete gets its name from the fact that most formulas use a mixture of water and cement with cellulose fiber. The fiber is usually acquired from recycled newspaper, lottery tickets and phone books. The mixture has the appearance and texture of oatmeal and is poured into forms and dried in the sun, much like the process for making adobe
.
Dried papercrete has very low strength, but fails by slow compression (due to the large air content and hence compressibility) rather than in a brittle
manner. Concrete and wood are not known for their insulating qualities; however, papercrete also provides good insulation.
Its R-value
is reported to be within 2.0 and 3.0 per inch (2.54 cm); papercrete walls are typically 10 to 12 inches thick (about 25–30 cm). Unlike concrete or adobe, papercrete blocks are lightweight, less than a third of the weight of a comparably-sized adobe brick. Papercrete is mold resistant and has utility as a sound-proofing material.
Research tests into papercrete have been carried out by Barry Fuller in Arizona and Zach Rabon in Texas. Fuller directs government-funded research on papercrete through the Arizona State University
Ira A. Fulton School of Engineering
. He is also head of a subcommittee for the American Society for Testing and Materials, and it is his goal to set standards that will lead to acceptance of the product within the architectural community and commercialization of the product, especially for affordable housing.
Structural tests have been completed on several papercrete formulas and Fuller claims the compressive strength of papercrete to be in the 140-160 psi range (0.96 - 1.1 MPa), while others like Kelly Hart claim 260 psi (1.7 MPa). For comparison, the compressive strength of concrete ranges from 15 Mpa to over 70 MPa (2200 - 10000 psi) depending on the application. A more useful measure of papercrete's properties is its stiffness
- i.e. the extent to which it compresses under load. Its stiffness is many times less than that of concrete, but sufficient for the support of roof loads in some low-height buildings.
Dried, ready-to-use papercrete has a rough surface. This increases its surface area and provides a very strong bond from one block to the next.
Papercrete has also been tested for its tensile strength
. Fuller notes that a papercrete block is the equivalent of hundred of pages of paper - almost like a catalog. Papercrete has very good shear strength as a block. Lateral load involves sideways force - the wind load on the entire area of an outside wall for example. Because papercrete walls are usually a minimum of twelve inches thick, and usually pinned with rebar
, they may be strong laterally.
Zach Rabon founded Mason Greenstar in Mason, Texas for the purpose of producing and selling a commercially viable papercrete block. His product, Blox Building System, is at present the only mass-produced commercial papercrete block in the market. He has built several residential structures with it.
The Mason Greenstar block had its genesis in a journey Rabon's father, Kent Rabon, made to Marathon, Texas
. The elder Rabon made the acquaintance of Clyde T. Curry, the proprietor of Eve's Garden Organic Bed & Breakfast and Ecology Resource Center.
Mr. Curry was an early proponent of papercrete and benefited from the lack of building regulations in the small mountain community of Marathon. Curry built four of the rooms at the bed and breakfast either partially or entirely out of papercrete and is in the process of building two more, in addition to a library and reception area, entirely out of papercrete.
Papercrete's ready moldability provides considerable flexibility in the designed shape of structures. Domed ceilings/roofs may be commonly constructed with this material.
Along with Fuller's work at Arizona State University, Curry's establishment has become a resource center for people interested in papercrete, and workshops are intermittently held there.
The Rabons had prior experience as homebuilders and are owners of a ready-mix cement plant in Mason. They have invested in research and testing on their product for several years. However, they consider their product a proprietary formula. They have filed for a separate patent even though a patent for papercrete had already been filed in 1928. The block developed by Mason Greenstar is known for its uniform shrinkage (all papercrete blocks go through a lengthy dry-time that involves some shrinkage), giving it a sharper edge.
Fuller has remarked that in tests he has performed on the Rabon block, it has outperformed other formulas.
Papercrete is claimed to have benefit of being a project that involves little cost to start. The materials are claimed to be cheap and widely available. Machinery suitable for small-scale construction is simple to design and construct.
When properly mixed and dried, the papercrete wall can be left exposed to the elements. In its natural state, it is a grey, fibrous-looking wall. For a more conventional look, stucco can be applied directly to it.
A study model home made of papercrete has been built at the Lyle Center for Regenerative Studies
. This study model is a sample of homes to be built for a sustainable community in Tijuana by students of California State Polytechnic University, Pomona
Since 2006 a small company based in England called Econovate Ltd has being developing together with the Engineer Department and the Manufacturing Department at Cambridge University a papercrete formula to be accepted by British Standard and a certification from BBA. This new mixture of papercrete is to withstand the wet and harsh English weather. Econovate has filed for a patent in 2007 on blocks and designed wall panels made of this papercrete formula. As of 2009 Econovate is in the process of developing this product and reaching the manufacturing trials stage.
Paper
Paper is a thin material mainly used for writing upon, printing upon, drawing or for packaging. It is produced by pressing together moist fibers, typically cellulose pulp derived from wood, rags or grasses, and drying them into flexible sheets....
with Portland cement
Portland cement
Portland cement is the most common type of cement in general use around the world because it is a basic ingredient of concrete, mortar, stucco and most non-specialty grout...
or clay
Clay
Clay is a general term including many combinations of one or more clay minerals with traces of metal oxides and organic matter. Geologic clay deposits are mostly composed of phyllosilicate minerals containing variable amounts of water trapped in the mineral structure.- Formation :Clay minerals...
and/or other soil added. First patented in 1928, it has been revived since the 1980s. Although perceived as an environmentally friendly material due to the significant recycled content, this is offset by the presence of cement. The material lacks standardisation, and proper use therefore requires care and experience. Eric Patterson and Mike McCain, who have been ascribed with independently "inventing" papercrete (they called it "padobe" and "fibrous cement"), have both contributed considerably to research into machinery to make it and ways of using it for building.
Manufacture
The paper to be used can come from a variety of sources. NewspaperNewspaper
A newspaper is a scheduled publication containing news of current events, informative articles, diverse features and advertising. It usually is printed on relatively inexpensive, low-grade paper such as newsprint. By 2007, there were 6580 daily newspapers in the world selling 395 million copies a...
, junk mail
Junk mail
Junk mail may refer to:* Junk Mail Publishing* Advertising mail* Spam , unsolicited electronic mail* Junk Mail * "The Junk Mail", an episode from the TV series Seinfeld...
, magazine
Magazine
Magazines, periodicals, glossies or serials are publications, generally published on a regular schedule, containing a variety of articles. They are generally financed by advertising, by a purchase price, by pre-paid magazine subscriptions, or all three...
s, book
Book
A book is a set or collection of written, printed, illustrated, or blank sheets, made of hot lava, paper, parchment, or other materials, usually fastened together to hinge at one side. A single sheet within a book is called a leaf or leaflet, and each side of a leaf is called a page...
s, etc. obtained from the local dump or from waste bins are all useful. Depending on the type of mixer used to pulp the mix, the paper may be soaked in water beforehand.
A typical homemade mixer uses a small electric motor
Electric motor
An electric motor converts electrical energy into mechanical energy.Most electric motors operate through the interaction of magnetic fields and current-carrying conductors to generate force...
mounted directly on a shaft with two four-inch square blades attached, resembling milk shake maker. This shaft is suspended in a plastic 55 gallon drum to mix the material.
Another homemade mixer is made from a trailer built from the rear end of a car, with the differential input pointed upward and a lawn mower blade attached. When the trailer's wheels turn, the differential gears spin and power the blades. The blade is placed in a large stock watering tank to mix the material. A baffle on the side of the tank forces the slurry back into the blade as it circulates. With this mixer it has been possible to make three or four wheelbarrows full of thick papercrete in about twenty minutes.
Paperpulp may be added to clay soils where sand is not available. The added paperpulp helps to minimize cracking when the material dries.
Standardization and Commercial Acceptance
As of 2007, papercrete lacks approval from the International Code CouncilInternational code council
The International Code Council , a membership association dedicated to building safety, fire prevention and energy efficiency, develops the codes used to construct residential and commercial buildings, including homes and schools. Most U.S. cities, counties and states that adopt codes choose the...
. This limits its range of use within the city limits of most incorporated United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
cities where building codes apply. It is not used as a load-bearing wall where building codes apply. However, its strength in model structures has been proven, and homes and small commercial buildings are being constructed. There is little or no evidence of its long-term durability at present.
In these small building projects, papercrete is being used as an in-fill wall
Wall
A wall is a usually solid structure that defines and sometimes protects an area. Most commonly, a wall delineates a building and supports its superstructure, separates space in buildings into rooms, or protects or delineates a space in the open air...
in conjunction with structural steel
Structural steel
Structural steel is steel construction material, a profile, formed with a specific shape or cross section and certain standards of chemical composition and mechanical properties...
beams
Beam (structure)
A beam is a horizontal structural element that is capable of withstanding load primarily by resisting bending. The bending force induced into the material of the beam as a result of the external loads, own weight, span and external reactions to these loads is called a bending moment.- Overview...
or other load-bearing elements.
Papercrete gets its name from the fact that most formulas use a mixture of water and cement with cellulose fiber. The fiber is usually acquired from recycled newspaper, lottery tickets and phone books. The mixture has the appearance and texture of oatmeal and is poured into forms and dried in the sun, much like the process for making adobe
Adobe
Adobe is a natural building material made from sand, clay, water, and some kind of fibrous or organic material , which the builders shape into bricks using frames and dry in the sun. Adobe buildings are similar to cob and mudbrick buildings. Adobe structures are extremely durable, and account for...
.
Dried papercrete has very low strength, but fails by slow compression (due to the large air content and hence compressibility) rather than in a brittle
Brittle
A material is brittle if, when subjected to stress, it breaks without significant deformation . Brittle materials absorb relatively little energy prior to fracture, even those of high strength. Breaking is often accompanied by a snapping sound. Brittle materials include most ceramics and glasses ...
manner. Concrete and wood are not known for their insulating qualities; however, papercrete also provides good insulation.
Its R-value
R-value (insulation)
The R-value is a measure of thermal resistance used in the building and construction industry. Under uniform conditions it is the ratio of the temperature difference across an insulator and the heat flux through it or R = \Delta T/\dot Q_A.The R-value being discussed is the unit thermal resistance...
is reported to be within 2.0 and 3.0 per inch (2.54 cm); papercrete walls are typically 10 to 12 inches thick (about 25–30 cm). Unlike concrete or adobe, papercrete blocks are lightweight, less than a third of the weight of a comparably-sized adobe brick. Papercrete is mold resistant and has utility as a sound-proofing material.
Research tests into papercrete have been carried out by Barry Fuller in Arizona and Zach Rabon in Texas. Fuller directs government-funded research on papercrete through the Arizona State University
Arizona State University
Arizona State University is a public research university located in the Phoenix Metropolitan Area of the State of Arizona...
Ira A. Fulton School of Engineering
Ira A. Fulton School of Engineering
The Ira A. Fulton Schools of Engineering is one of the 24 independent school units of Arizona State University. It provides undergraduate and graduate programs for engineering, computer science, and construction students.-History:The Fulton School was started in 1954 as the College of Applied...
. He is also head of a subcommittee for the American Society for Testing and Materials, and it is his goal to set standards that will lead to acceptance of the product within the architectural community and commercialization of the product, especially for affordable housing.
Structural tests have been completed on several papercrete formulas and Fuller claims the compressive strength of papercrete to be in the 140-160 psi range (0.96 - 1.1 MPa), while others like Kelly Hart claim 260 psi (1.7 MPa). For comparison, the compressive strength of concrete ranges from 15 Mpa to over 70 MPa (2200 - 10000 psi) depending on the application. A more useful measure of papercrete's properties is its stiffness
Stiffness
Stiffness is the resistance of an elastic body to deformation by an applied force along a given degree of freedom when a set of loading points and boundary conditions are prescribed on the elastic body.-Calculations:...
- i.e. the extent to which it compresses under load. Its stiffness is many times less than that of concrete, but sufficient for the support of roof loads in some low-height buildings.
Dried, ready-to-use papercrete has a rough surface. This increases its surface area and provides a very strong bond from one block to the next.
Papercrete has also been tested for its tensile strength
Tensile strength
Ultimate tensile strength , often shortened to tensile strength or ultimate strength, is the maximum stress that a material can withstand while being stretched or pulled before necking, which is when the specimen's cross-section starts to significantly contract...
. Fuller notes that a papercrete block is the equivalent of hundred of pages of paper - almost like a catalog. Papercrete has very good shear strength as a block. Lateral load involves sideways force - the wind load on the entire area of an outside wall for example. Because papercrete walls are usually a minimum of twelve inches thick, and usually pinned with rebar
Rebar
A rebar , also known as reinforcing steel, reinforcement steel, rerod, or a deformed bar, is a common steel bar, and is commonly used as a tensioning device in reinforced concrete and reinforced masonry structures holding the concrete in compression...
, they may be strong laterally.
Zach Rabon founded Mason Greenstar in Mason, Texas for the purpose of producing and selling a commercially viable papercrete block. His product, Blox Building System, is at present the only mass-produced commercial papercrete block in the market. He has built several residential structures with it.
The Mason Greenstar block had its genesis in a journey Rabon's father, Kent Rabon, made to Marathon, Texas
Marathon, Texas
Marathon is a census-designated place in Brewster County, Texas, United States. The population was 470 in 2007, after growing from 455 in 2000, but had decreased to 430 by 2010.-Geography:Marathon is located at ....
. The elder Rabon made the acquaintance of Clyde T. Curry, the proprietor of Eve's Garden Organic Bed & Breakfast and Ecology Resource Center.
Mr. Curry was an early proponent of papercrete and benefited from the lack of building regulations in the small mountain community of Marathon. Curry built four of the rooms at the bed and breakfast either partially or entirely out of papercrete and is in the process of building two more, in addition to a library and reception area, entirely out of papercrete.
Papercrete's ready moldability provides considerable flexibility in the designed shape of structures. Domed ceilings/roofs may be commonly constructed with this material.
Along with Fuller's work at Arizona State University, Curry's establishment has become a resource center for people interested in papercrete, and workshops are intermittently held there.
The Rabons had prior experience as homebuilders and are owners of a ready-mix cement plant in Mason. They have invested in research and testing on their product for several years. However, they consider their product a proprietary formula. They have filed for a separate patent even though a patent for papercrete had already been filed in 1928. The block developed by Mason Greenstar is known for its uniform shrinkage (all papercrete blocks go through a lengthy dry-time that involves some shrinkage), giving it a sharper edge.
Fuller has remarked that in tests he has performed on the Rabon block, it has outperformed other formulas.
Papercrete is claimed to have benefit of being a project that involves little cost to start. The materials are claimed to be cheap and widely available. Machinery suitable for small-scale construction is simple to design and construct.
When properly mixed and dried, the papercrete wall can be left exposed to the elements. In its natural state, it is a grey, fibrous-looking wall. For a more conventional look, stucco can be applied directly to it.
A study model home made of papercrete has been built at the Lyle Center for Regenerative Studies
Lyle Center for Regenerative Studies
The John T. Lyle Center for Regenerative Studies, informally called LCRS, is a research facility at California State Polytechnic University, Pomona in Pomona, California, United States. Based on regenerative principles of sustainable design and sustainable agriculture the center offers both a...
. This study model is a sample of homes to be built for a sustainable community in Tijuana by students of California State Polytechnic University, Pomona
California State Polytechnic University, Pomona
California State Polytechnic University, Pomona, or Cal Poly Pomona, is a public university located in Pomona, California, United States...
Since 2006 a small company based in England called Econovate Ltd has being developing together with the Engineer Department and the Manufacturing Department at Cambridge University a papercrete formula to be accepted by British Standard and a certification from BBA. This new mixture of papercrete is to withstand the wet and harsh English weather. Econovate has filed for a patent in 2007 on blocks and designed wall panels made of this papercrete formula. As of 2009 Econovate is in the process of developing this product and reaching the manufacturing trials stage.
Do it Yourself
Papercrete is rapidly gaining a groundswell of support among "do it yourself" builders. It is claimed to be a very attractive building material due to its very low cost, light weight, and high performance. Many owner/builders are contributing to furthering the technology and sharing their experiences over the internet through resources such as "Papercreters".Similar Materials
There are different earth-paper mixes promoted under different names. A mix that uses clay as a binder instead of Portland cement is often referred to as "Hybrid Adobe", "Fidobe", or "Padobe".See also
- Asbestos cementFibroFibro, the shortened form of "Fibrous Cement" - or "Fibrous Asbestos Cement", FAC, is a building material made of compressed fibres cemented into rigid sheets....
- Paper mache
- PykretePykretePykrete is a composite material made of approximately 14 percent sawdust or some other form of wood pulp and 86 percent ice by weight. Its use was proposed during World War II by Geoffrey Pyke to the British Royal Navy as a candidate material for making a huge, unsinkable aircraft carrier...
- Fiber Cement
- Concrete Cloth