Working your walls with Earth plaster: play in the mud

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mudding_4If you think smearing mud all over your living room walls is either an act of insanity or vandalism, think again! Without having to build a straw bale A straw bale is a bundle of straw tightly bound with twine or wire. Bales may be square, rectangular, or round, depending on the type of baler used.

When bales are used to build or insulate buildings, the straw bales are commonly finished with plaster. house or a mud hut, you can experience the beauties and benefits of earthen earth·en


1. Made of earth or clay: an earthen fortification; an earthen pot.

2. Earthly; worldly. (clay-based) plasters by doing a bit of eco-remodeling in the house you live in right now. You can totally change the personality of a room that is tired or sterile with a coat of mud on the walls.

Many colors are possible, mostly in muted hues. Earthen plasters, with their slight--or major if you choose--variations in surface texture, reflectivity re·flec·tiv·i·ty

n. pl. re·flec·tiv·i·ties

1. The quality of being reflective.

2. The ability to reflect.

3. , and color bring a sense of life to a room or a whole house. They lend a handmade feel, often in a classic Old World sense. Some finishes look almost like leather or marble, but there is a lot of room for creativity. You can smooth and round corners and transform boring flat sheetrock by adding a bit of sensuous undulation undulation /un·du·la·tion/ (un?ju-) (un?dyu-la´shun)

1. a wavelike motion; see also pulsation.

2. a wavelike appearance, outline, or form. or trowel or hand marks. Most people feel more comfortable in rooms that have some variation in wall surface, shape, texture, and color, perhaps because we humans have been housed for millennia in caves, and houses of wood, stone, mud and thatch--not in flat-planed boxes!

If you want to start with a small project, try accent touches around doorways or windows, over a brick fireplace, or in an alcove. You can even do relief sculptures on the wall, sometimes with the help of simple armature armature, in art: see sculpture. Armature

mudding_2That part of an electric rotating machine which includes the main current-carrying winding. like screws. Mosaic with tile or mirror is another option, as well as a form of high-relief stenciling. With the addition of oil and wax, people have even made sinks and bathtubs out of mud! Plastering plastering, house construction technique involving the application of plaster to walls and ceilings, exterior plasterwork being of a different composition and generally known as stucco. the exterior of an existing home is possible in some cases, but has different issues to address than interior work.


Clay-based plasters represent less environmental cost than cement or gypsum-based products because they are not heated to high temperatures, which take a huge amount of energy, with its resulting pollution and greenhouse gasses. They are not as resistant to impacts or abrasion as the other common stucco/plaster options, but with reasonable forethought fore·thought

1. Deliberation, consideration, or planning beforehand.

2. Preparation or thought for the future. See Synonyms at prudence. about where to apply them, as well as attention to proper mixing and application, they should do fine in many situations.

Unless certain pigments are added for color, earthen plasters (and paints) are very low on the toxicity scale--they are the original "no VOC (Vertical Online Community) See vertical portal. " (volatile organic compound volatile organic compound Environment Any toxic cabon-based (organic) substance that easily become vapors or gases–eg, solvents–paint thinners, lacquer thinner, degreasers, dry cleaning fluids ) wall coatings. Iron oxides and ochres are the safest pigments. Do be careful not to breathe the dust of clay or sand (or anything) while mixing, as this can result in serious lung problems.


Earthen plasters can get wet on occasion, but repeated driving rains, constant wetness, or excessive humidity are likely to result in some degree of damage. Luckily, clay-based plasters are easier to fix than concrete stuccos. What about our famously humid climate? It's all about choosing where to put your plasters. They do best in places that receive light and air circulation, not in dark, damp places that already grow mildew. However, because of clay's ability to molecularly absorb water without getting wet (to a point, of course), then to let it evaporate easily when drier air wafts past, earthen plasters with the right ingredients can be surprisingly resistant to mold. Some museums have even earth-plastered their walls to help moderate swings in humidity, which can damage valuable works of art.

Mold doesn't actually grow on clay or sand, but the "organic matter" ingredients of plaster could feed it. However, experience has shown that it has to be a pretty bad situation for a mold problem to develop (little sun or air circulation). Clay has been found to protect straw used as insulation in Tudor-style timber frames in Germany for hundreds of years. Hydrated hy·drat·ed


Chemically combined with water, especially existing in the form of a hydrate.

Adj. 1. hydrated - containing combined water (especially water of crystallization as in a hydrate)

hydrous lime-based plasters (which can also have clay in them) are even more mold-resistant due to their alkalinity al·ka·lin·i·ty


The alkali concentration or alkaline quality of a substance that contains alkali.


1. the quality of being alkaline.

2. . Unlike garden lime, hydrated lime (builder's lime) is heated to a high temperature (similar to cement) to change its molecular structure. If treated correctly, it slowly turns back to limestone as it cures on your wall.


mudding_1Plasters are usually made up of three main components: binder, aggregate, and fiber. In this case, clay is the binder, sand is the aggregate, and straw or manure from grass-eating animals serves as the fiber (the manure completely loses its odor when dry). There are also many potential additives that improve the workability, durability, or water-resistance of the finished product. I have found that ingredients that are sticky when wet generally become hard when dry, thus adding to the durability of this relatively "soft" coating. Some common additives include milk products, wheat paste (like old-fashioned wallpaper paste), oil, paper pulp Paper pulp is a material for making paper. It is usuallly cellulose fibre, and could be wood pulp or non-wood pulp See also

* Pulpwood

* Woodpulp

External links

* Paper pulp properties

* Paper pulp grades

, and cactus juice where lots of prickly pear prickly pear: see cactus. prickly pear

Any of a group of flat-stemmed, spiny opuntia cacti (see cactus), native to the Western Hemisphere, or the edible fruit of certain species. cacti grow. Borax borax or sodium tetraborate decahydrate (s?'d??m t?'tr?bôr'?t d?k'?h?'dr?t), chemical compound, Na2B4O7·10H2O; sp. gr. 1. has sometimes been added to retard mold, especially in earthen paint, which is sometimes done over a plaster or "regular" wall for color or other decorative effect.

People hate to hear this, but there is literally millions of plaster "recipes." I once heard two of the most experienced earthen plasterers in the Southwest state that they had never made the same mix twice. So it's best to approach it with the attitude that it is all a big experiment, as is all of life! Of course, basic knowledge goes a long way in mixing up something that will work well. And it is good to remember that lots of things will work well--many ways exist to "do it right." There are no "mess ups," just interesting lessons to learn from. Always make test patches; it is just part of the process.


The plaster has to be able to grip the wall well enough so that it doesn't fall off. The thicker the coat, the heavier it is and the more likely not to stick. There are several potential solutions to this. Apply a primer coat of masonry adhesive or wheat paste with sand added, glue or staple up burlap, install stucco mesh, reed matting or jute, or rough up a smooth texture all present good possibilities. You may not need to modify the surface at all--do some large test patches and see how well they stick.

Plasters can he applied with hands or trowels, and are sometimes smoothed with trowels or sponges or wooden floats. Sometimes plasters are burnished bur·nish

tr.v. bur·nished, bur·nish·ing, bur·nish·es

1. To make smooth or glossy by or as if by rubbing; polish.

2. To rub with a tool that serves especially to smooth or polish.

n. or polished with a trowel or piece of plastic when they are partially dry to make them really smooth. It doesn't take most people long to get the hang of to learn the method or arrangement of; hence, to become accustomed to.

See also: Hang the basics, but it is definitely hard work if you are going to be doing a large area. Of course, having someone with experience to teach you the techniques (and help out!) is ideal.

If you don't want to try mixing your own, look into the ready-mixed earthen plasters that you could trowel on yourself or hire an experienced person to apply. You can also buy clay and fine sand from a ceramics supply company instead of digging it up yourself. If you want to make your own plasters from the soil instead of from a bag--and I highly recommend it for the fun and connectedness and pride you will feel--do some further reading and/or take a class. I, for one, am so happy to see the beautiful clay of this area grace more and more buildings--it's local, it's fun, and it works!



American Clay Finishes. Earth plaster from clays and minerals found in the US. 866-403-1634.

Pure Life. AFM (Atomic Force Microscope) A device used to image materials at the atomic level. AFMs are used to solve processing and materials problems in electronics, telecom, biology and other high-tech industries. sealers, adhesives and coatings. Atlanta GA. 800-510-8342.

Shelter Ecology. AFM sealers, adhesives and coatings. Asheville NC. 828-225-2829.

Med Imports. Distributor of Terramed earthen plasters from Europe. 866-363-6334.

Highwater Clays. Source of clays and fine sand in large quantities. 828-252-6033.


mudding_3Earthaven Learning Center. This educational organization based at Earthaven EcoVillage offers a variety of natural building courses, including earthen plasters and paints. Other topics are offered as well. 828-664-9935.

Kleiwerks. Offers local as well as international natural building classes, many of them "start to finish," with a focus on adobe.

Cob Cottage Company. Started by Ianto Evans, Welsh cob revivalist. Located in Oregon. They mostly host classes on the West coast


The Natural Plaster Book by Cedar Rose Guelberth and Dan Chiras, 2003, New Society Publishers. This book mostly focuses on plastering strawbale buildings, but goes into plenty of detail about how to make your own earthen plasters from your local subsoil subsoil

Layer (stratum) of earth immediately below the surface soil, consisting predominantly of minerals and leached materials such as iron and aluminum compounds. Humus remains and clay accumulate in subsoil, but the teeming macroscopic and microscopic organisms that make . It also covers hydrated-lime based plasters and gypsum gypsum (j?p's?m), mineral composed of calcium sulfate (calcium, sulfur, and oxygen) with two molecules of water, CaSO4·2H2O. It is the most common sulfate mineral, occurring in many places in a variety of forms. plasters and other natural finishes.

The Hand-Sculpted House by Ianto Evans, Michael Smith Michael or Mike Smith may refer to: Journalists

* Michael Smith (sports reporter), American sports reporter for the The Boston Globe and ESPN

* Mike Smith (television presenter), British television and radio presenter

* Linda Smiley, 2002, Chelsea Green Publishers Mainly about building cob homes, lots of good basic information about plasters and other natural finishes is included. A refreshingly radical approach to the building process is presented.

The Cob Builders Handbook by Becky Bee. 1997. Groundworks. Simply and inspirationally written about how to build a cob house, including earth plasters and other natural finishes.

The Last Straw The last of a series of annoyances or disappointments that leads one to a final loss of patience, temper, trust, or hope. This periodical covers all kinds of natural building. It is very informative--not a slick publication.

The Natural Home. A slick publication available on newsstands. Good for ideas, but does not include "how-to."


Peter Bane BANE. This word was formerly used to signify a malefactor. Bract. 1. 2, t. 8, c. 1. has written a variety of books on permaculture per·ma·cul·ture

A system of perennial agriculture emphasizing the use of renewable natural resources and the enrichment of local ecosystems.

[perma(nent) + (agri)culture. . Visit him at

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