If you’d like to create a warm and inviting living space, consider
using homemade, eco-friendly paints. Using natural materials is a great way to bring the outdoors in, and they’re easier
on your home because they can allow painted surfaces to release moisture naturally. Plus, most commercially manufactured paints
contain toxic materials or petroleum-based ingredients that are energy-intensive to produce.
There are several eco-friendly options on the market, but their cost (up
to twice as much as conventional paint) can be prohibitive to painters on a budget. Many DIYers are choosing instead to make
their own paint. Creating your own paint is considerably less expensive and can be an extremely satisfying endeavor for anyone
whose goal is self-reliance. Mixing your own paint is sometimes the only way to achieve a specific color or effect. In fact,
natural paints offer unique finishes very different from those of manufactured products.
There are numerous combinations to choose from when attempting to create
the perfect paint for a particular situation. What follows is a guide to understanding natural paint, recipes for some of
the easiest and most common types and photos of each kind to inspire you. When you’re ready to experiment with even
more natural materials, a good place to start is The Natural Paint Book by Lynn Edwards and Julia Lawless.
What’s in a Gallon?
In its most basic form, paint consists of color
(the pigment) and the glue in which the pigment is suspended (the binder). Many paints also contain ingredients that add texture
and bulk (fillers), a thinner (the solvent) and other additives, such as biocides and drying catalysts.
Pigments. Safer alternatives to the toxic compounds and heavy metals used
to color conventional paint include natural pigments derived from plants, insects, iron oxides and minerals. These are usually
in powder form at artists’ supply stores.
Binders. Binders keep paint glued to a surface. The acrylic and vinyl binders
in commercial paints are derived from the byproducts of refining crude oil. The binders in natural paints rely instead on
materials such as starch (from flour), casein (the protein in milk) and linseed oil (from pressed flax seeds).
Fillers. Fillers create texture and add bulk to paint. Common fillers include
whiting (powdered chalk), talcum, limestone, silica and marble. Clay is a popular filler to pair with flour, because it reinforces
the binding ability of starch, and it’s abundant and potentially free if you have clay soil.
Solvents. Solvents, or thinners, help achieve a workable consistency. The
solvents in commercial paints are usually made from organic materials, but they will evaporate or “outgas,” causing
that new paint smell. The outgassing of these volatile organic compounds (VOCs) can cause headaches, nausea, dizziness, blurred
vision and fatigue, especially in areas that are not well ventilated. The hazards are significantly worse for people who paint
regularly. Natural solvents such as citrus thinners and natural turpentine are preferable, but they can still emit low levels
of VOCs.
Additives. Commercial paint manufacturers frequently include several additives
in their products, but they aren’t required to list them on the can. Additives include plasticizers, foaming and antifoaming
agents, driers, biocides that inhibit the growth of mold, and ingredients that improve water resistance or opacity.
Flour Paint
Flour paint is among the simplest and most versatile of all
homemade paints. It can be applied to most interior surfaces, and the proportions don’t have to be as exact as for other
kinds of paint. You can use many types of grain flour as the binder, but wheat flour is the most common choice.
Flour paint typically uses clay as the filler, but any combination of finely
ground inert materials, such as chalk, mica, marble, limestone or silica will work. If you want a textured surface, use more
coarsely screened materials. Just make sure you’ll still be able to apply the finished product with a brush!
Flour paint is too thick for use with a roller, and it tends to be hard on
brushes. Choose inexpensive brushes with natural bristles — nothing fancy — and stock up. When first applying
flour paint, the brush marks will be evident. To remove the marks, wait until the paint has begun to dry and smooth over with
a damp sponge or clean, damp brush. Going over the surface again when the paint has become leathery will also help reveal
the mica or other filler.
Basic Flour Paint
Yields 1 1/2 quarts
1 cup flour
5
1/2 cups cold water
1 cup screened clay filler (clay can be purchased in a wide variety of colors)
1/2
cup additional powder filler, such as mica
- Mix flour with 2 cups cold water, whisking to remove lumps.
- Bring 11/2 cups water to boil, then add the flour water from Step 1.
- Turn heat to low, stirring until thick paste develops. Remove from heat.
- Dilute the paste with 2 cups water, a little at a time.
- In a separate work bowl, combine clay with powder filler.
- Add filler mixture to diluted flour paste until desired consistency is achieved.
Oil Paint
Oil paint is suitable for exterior surfaces, and you can clean
oil-painted surfaces regularly without damaging the paint. (You’ll need to use a solvent to clean brushes and equipment.)
Oil paints can take a long time to dry — some will never completely harden — but this property gives the paint
the advantage of remaining elastic as surfaces naturally swell and shrink.
Natural oil paints typically are made with linseed oil and a natural solvent,
such as pure turpentine or citrus thinner. Choose raw linseed oil or linseed stand oil, which has been heated to a high temperature,
making it more durable. (Avoid boiled linseed oil, which can contain a variety of ingredients that speed drying time, but
may be hazardous to your health.)
When painting bare wood, the finished surface will look much better if you
wet the wood with warm water and sand it before painting. Priming helps seal wood against moisture and creates a better bond
with the finish. This is especially important if the paint is intended to cover the wood’s grain.
Basic Oil Primer
Combine equal parts linseed oil and natural solvent.
Then apply a thin coat, in the direction of the grain, and wipe off any excess. When the first coat is dry (about 48 hours),
apply a second coat.
Basic Oil Paint
Your surface will be ready for paint about 48 hours after
the primer has dried. It is difficult to provide precise recipes for oil paints, because pigments absorb oil to varying degrees.
Pour several tablespoons of linseed oil in a bowl and add pigment, a little at a time, until a doughy paste forms. Then you
can add more oil just until the mixture flows. Next, add solvent until the paint reaches your desired consistency. Pour the
finished mixture through a strainer to remove lumps.
Basic Oil Glaze
An oil glaze can serve many purposes. Sometimes you will
want to put a glaze over flour or milk paints to increase water resistance. Oil glazes also make nice wood stains, with or
without added color.
Yields approximately 2 cups.
- Dissolve 1 teaspoon each pigment and whiting (powdered chalk) in approximately
1/2 cup linseed oil.
- Stir in an additional 1/2 cup linseed oil.
- Add 2/3 cup natural solvent and 2 tablespoons whiting, whisking to remove
lumps.
Casein Paint
Casein is the protein component of milk, and it makes great
paint. Casein paint lasts indefinitely, is excellent on many surfaces, isn’t prone to fungal growth, and leftover paint
can be safely composted. Casein paint is prepared from the curds of nonfat milk (fats inhibit drying time). These are also
known as quark, and are available in gourmet grocery stores, but they’re easy to make yourself. Or you can purchase
concentrated casein powder from a natural paint supplier. (To use casein powder instead of quark, just follow the label’s
instructions.)
Casein paint must be mixed to specific proportions to prevent cracking, peeling
and dusting off. It’s important to allow each coat to dry completely, because the paint will become more and more opaque
as it dries. Avoid the temptation to apply extra-thick coats!
In order to become an adhesive binder, casein must be combined with an alkali
such as lime. (You can use borax instead, but lime-casein paint is much more water resistant.)
Casein Paint with Lime
Yields about 1 quart
1 gallon nonfat milk
2
1/2 ounces “Type S” lime (dry powder available at hardware stores)
2 1/2 cups water
Natural
earth pigment (more or less depending on desired color)
6 cups filler (usually whiting)
- Leave milk in a warm place for a few days to curdle. Then pour through a
colander lined with cheesecloth. You should have about 2 cups of curds. The whey can be composted.
- Mix curds and lime powder in a blender. Add a little water if the mixture
isn’t blending well. Strain to remove any lumps.
- Add water to the binder immediately after it is prepared.
- Dampen and crush pigments. Add them to the mixture a little at a time until
desired color intensity is achieved.
- Stir in filler.
Casein Paint Adjustments
After mixing your paint, test it on a small
area of your surface and let it dry completely. If it doesn’t spread easily, add some water. If it dusts, add more binder.
If it’s too thin, add more filler. If the color isn’t rich enough, add more crushed pigment.
Expert Tips
- When making your own paint, it is important to experiment, test, experiment,
and test some more. Keep it fun! If you play for a while first, you’re sure to end up with a beautiful combination of
rich colors and interesting textures.
- For best results, clean all surfaces thoroughly before painting.
- Homemade paints contain food ingredients and should be used soon after mixing.
You can refrigerate them, but the binding ability may diminish.
- It may be difficult to create exactly the same color over and over again.
Try to mix as much paint as you can reasonably use in one work session.
- Exercise caution when using linseed oil. Crumpled oil-soaked cloths can
spontaneously combust, so be sure to wash all cloths and other materials before disposal.
- Exercise caution with all powdered and caustic materials, especially lime.
Wear gloves and goggles.
Which Paints for Which Surfaces?
When selecting which kind of paint to
mix for a particular surface, your first consideration should be whether the surface is interior or exterior. Then select
a paint that is appropriate to the type of surface.
Interior surfaces: flour; casein; oil
Exterior surfaces: oil; flour in
mild climates; casein in extremely mild, non-humid climates
Bare wood: oil; flour; casein
Stone: flour; casein
Bare
drywall: casein; flour (but not over joint compound)
Wallpaper: flour; casein
Earthen plaster: flour; casein
Gypsum
plaster: flour
Masonry (cement, lime, unglazed brick, unpainted earth): flour; casein; oil
Painted surfaces, sanded:
flour; casein
Surfaces that require frequent cleaning: oil