Let's revisit some of the natural and effective finishes we have used for centuries before the days of chemical finishes.
1. Wood Finishes
Natural Oils and Waxes
|Photo from homesteadhouse.ca|
Hemp Oil and Walnut Oil are other alternatives for wood finishing. They do have a scent, which I would consider pleasant, but I would test for your own sensitivities (and allergies!) by buying samples from Vitacost. You get 10$ off with that link! (They ship to Canada and US).
Linseed, Tung, Hemp and Walnut Oil are drying oils (although some claim Walnut is a semi-drying oil); they all penetrate, harden and preserve wood, and provide a long-lasting finish that does not turn rancid.
I used Hemp Oil on all the interior wood in my chemical-free tiny home. One problem is hemp oil with no pigments is not a very durable finish when dusty feet and hands come into regular contact with it... hmmm I have not solved this problem yet!
Wood can then be finished with a beeswax polish for extra durability. I don't know how long it takes to dry but I found that it was too sticky for too long and attracted more dust and grime on frequently used surfaces. I will be using beeswax on clay plaster in the kitchen to provide a water-resistant finish. This Beeswax/Carnauba Polish would be great, or you can make your own, but use one of the drying oils listed above. I would not recommend using olive oil or other (non-drying) oils that can go rancid on wood. Here's a how-to on finishing wood with natural oil and wax.
Each oil on its own will tint the wood to a varying degree, so you should test for the look you want to achieve - you might find that you don't need a stain at all.
Non-toxic milk paint pigments can be used as a stain applied to the raw wood before finishing with oil and wax. I will be writing a how-to for these pigments as they are very tricky to work with!
I have used ECOS sealer on the wood in the kitchen as it is a little more durable than hemp in the kitchen. I also wanted something that did not darken the wood as much as hemp. I can't recommend this sealer enough though the shipping was very expensive.
2. VOC-Free Paint?
Apart from that, there are a myriad of paints claiming to be green or zero VOC. It's not easy to find out exactly what is in them, and some ingredients like biocides might not be listed. For example, conventional manufacturer - Benjamin Moore makes a "zero-VOC" paint that is high-quality, and comes in great colours, but it was totally intolerable for me while wet.
Here are some alternatives that claim to be non-toxic and zero VOC that you will have to test against your own sensitivities. The most natural ones are the clay-based paints.
Green Planet Paints - (Natural Source, Clay-Based Paint) available online, and in specialty paint stores in Canada and the US.
Auro Natural Paints - (Natural Source, Clay-Based Paint) available online, ships to US and Canada.
Mythic Paint - The green building supply store in Vancouver claims that Mythic is the best of the non-toxic acrylics. When dry it seemed totally fine but I'm still not certain of it's safety for MCSers when wet. I am using the interior line inside my chemical-free tiny house though I cannot totally vouch for it's lack of toxicity - like all paints, there are a number of additives that are not disclosed. If you are in the US it's easy to order it online and in Canada you have to get it at specialty paint or green building supply stores.
YOLO Colorhouse - Once you get past the name (sigh), this paint comes in a pretty good range of colours and they can custom match a colour for you. What exactly is in it no one can tell you. I have heard of many EIs who can tolerate it and many who think Mythic is better. It's available in stores across Canada and the US and online @ YOLO Colorhouse.
AFM Safecoat Zero VOC Paint- Contains no formaldehyde, ammonia, crystalline silica, or ethylene glycol. Tintable to thousands of colors with zero VOC colorants. Recommended by many EIs as well.
If you are using magnesium oxide board you will need to prime before painting AFM Safecoat Low VOC Transitional Primer, or YOLO Colorhouse Interior Primer.
Plaster is applied directly to earthen walls or pumice-crete.
There are clay-based plasters and lime-based plasters. I prefer lime because it is naturally mould resistant. Plasters can be tinted with natural pigments. Here is a a more detailed post on my experiences using clay plaster and limewash in my tiny house.
To learn more, get yourself a copy of The Natural Plaster Book.
4. Earthen Floor Finishes
If you don't have ox blood on hand, no problem, you can seal your earthen floor with any of the hardening oils we talked about under wood finishes (above). I would use Hemp Oil. This blogger claims that Walnut Oil went rancid with time. Beeswax can also be used in the final coat for extra protection if desired.
Sealing Toxic or Exterior Wood
If you are buying new wood-framed windows, the wood will likely have been treated with fungicides. Unless you are using old windows (which could pose problems with leaks), or aluminum-framed windows - not as cute, let's be honest - then your best bet is to seal in the toxins in your wood frames with AFM Safecoat Safe Seal, AFM Safecoat Transitional Primer, or B-I-N Shellac Base Primer & Sealer).
To protect exterior wood against the elements we can use something a little stronger (as the VOCs will not be within the building envelope) like: AFM Naturals Clear Penetrating Oil, or Sinan Company N. 253 Natural Undercoat Enamel (if you can find that in-store).
Plywood which has been treated with formaldehyde (almost all of it has!) can be sealed with B-I-N Shellac Base Primer & Sealer.
Sealing Tile, Concrete, Stone
For sealing grout use AFM Safecoat Grout Sealer or AFM Safecoat Safe Seal.
100% Tung Oil cut with Citrus Solvent can be used to seal stone, including granite and marble, as well as brick and concrete. I wouldn't use it in the shower area, but for a kitchen counter-top or other tiled area it could work. Here's a how-to. And again this is a pure, natural oil, but it has a scent that could be problematic for the chemically sensitive - test before using.
Sealing Joints or Ducts
RCD #6 Mastic I used Murco as a joint compound and found it totally tolerable. It has cracked at the joints which is something other builders have noted as well.
Paula Baker-Laport's: Prescriptions for a Healthy Home has been indispensable in informing this post. Get it here (Canada), or here (USA).
1 biocides, ammonia, crystalline silica, ethylene glycol, phthalates, isocyanate, mineral spirits, benzene, propane sulfone, petroleum distillates, nitrobenzene, ammonia, naphtha, and phenol. Sources: North Carolina Cooperative ExtensionService, Grassroots Info, & Cleveland Clinic .