In searching for biofriendly white surfaces, I found a nice blog post from quite awhile ago that surveys bio-friendly paint options.
Since the article is already 14 years old, I will repost below for posterity:
Make Safe, Natural Paint
Natural paint offers a sustainable and inexpensive way to add unique colors to your home.
Although several eco-friendly options on the market, many DIYers are choosing to make natural paint using natural materials instead.
Photo by Heather Brown
If you’d like to create a warm and inviting living space, consider using homemade, eco-friendly natural paint. 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.
- 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
Natural Paint Recipes
Are you ready? One of these mixes should get the job done and then some.
Natural Paint Materials
One or more of these vendors should have the necessary ingredients.
Commercial Eco-friendly Paints
If you decide you’d rather buy pre-mixed paint after all, consider one of these vendors.