Are Eco-friendly Materials Durable?
In short, Yes!
There are many natural materials that are incredibly durable. The ecosystem has evolved over millennia to be resilient in the face of the ever-changing challenges of life on Earth. The scorching sun, frigid winter temperatures, drought, monsoon rains, and predators all incentivize living things to naturally develop defenses which make them more durable and resilient to these challenges. Waxy, hydrophobic rainforest leaves, antibiotic fungi, and fire-resistant pine cones are just a few notable examples.
In fact, many artificial, toxic materials are merely lab-reproduced versions of naturally-occurring biological defense mechanisms. Take a look at the Biomimicry Institute which works to promote and share the inventions of nature with human innovators.
In other ways, eco-friendly materials can be notably less durable. Because all living things degrade and die, so to will the biological compounds and structures that lifeforms produce. However, when chosen and assembled with care, natural materials can provide impressive, long-term solutions for your building needs. There are also many natural, minimally processed metals which can provide outstanding structural and design benefits.
In this introductory article, we’ll cover just a few materials you might want to look into when building your Eco Van or eco-friendly tiny house.
Cork
Cork comes from the Cork Oak (Quercus suber), which grows natively around the Mediterranean, and is one of the most sustainable biological industries on the planet! The cork production within the country of Portugal is particularly revered for its sustainability practices, where harvesters carefully remove the outer phellem layer of bark by hand from a mature tree without hurting the tree itself. The tree is able to continue growing and reproduce a new layer of cork every 12 years or so. Cork Oak habitats also are home to some endangered species, so their protection is critical.
Cork is comprised of a hydrophobic material called Suberin which is why it’s commonly used for wine bottle stoppers, but it’s durability doesn’t stop there. It’s also impermeable, buoyant, elastic, mildew-proof, as well as fire and insect retardant. Scraps from solid cork products can also be naturally fused together with the resins already present within the material to create insulation panels with an insulation value of R4 per inch, which is similar to polystyrene.
Hardwoods & Cedar
Many varieties of hardwoods and cedars have been used for millennia for their durability against rot and decay, as well as their insecticide, fungicide, and antibacterial properties. White Oak, Western Red Cedar, and Eastern Cypress are particularly desirable. Redwood and Mahogany are also extremely durable woods, however a long history of unsustainable harvesting has led to mass deforestation and ecosystem degradation. It’s important that when you look for durable woods products that you choose sustainably harvested woods whenever possible.
When selecting wood for your project there are two certification standards that you can look for to choose a more eco-friendly product. These certifications can be difficult to find at major retailers like Home Depot or Lowe’s, but your local lumber yard, or cabinet or furniture maker may be able to help you.
Sustainable Forestry Initiative (SFI) — Their forest management standard covers important aspects of sustainable forestry like the protection of biodiversity, endangered species and wildlife habitats, sustainable harvesting, the protection of water quality, and forest regrowth and regeneration. The organization has been criticized by the Sierra Club and other organizations for conflicts of interest with private stakeholders, and some of their forestry partner’s lack of adherence to their standards. Despite this, this certification is considered to be the most robust and well-managed.
Forest Stewardship Council (FSC) — Their mission is to "promote environmentally appropriate, socially beneficial, and economically viable management of the world's forests.” However, the FSC has been more widely criticized by major organization such as Greenpeace and the Rainforest Foundation for the FSC’s use of old growth forest wood, and their lack of oversight on the certification process. While this certification might hold less “eco-friendly weight” than SFI, if you only have the option of choosing FSC wood, it’s still better than nothing!
Another option is to look for a local reclaimed wood supplier, or to ask your local lumber yard if they have any old scraps or ‘seconds.’ Because the quantities you’ll need to build a van are relatively small, you may be able to find a great deal on reclaimed woods that would otherwise be deemed unsustainable. Reusing/recycling hardwoods is a great way to obtain high quality, durable wood at an affordable price and because these wood varieties are naturally durable to the elements, there’s a good chance that some sanding or re-planing will bring the wood back to its original state.
Further still, the durability of hardwoods and cedar allow you to leave the wood unfinished or to finish it with a simple drying oil to preserve the natural look and feel of the wood without the need to coat it in toxic polyurethane or paints.
Tung Oil
This drying oil, derived from the nut from the deciduous Tung Tree (Vernicia fordii) of southeast Asia, has been used for thousands of years to protect wood from water, salt, dirt, and decay. Like linseed or safflower oil, it is considered a drying oil, and polymerizes when exposed to air. That’s a fancy way of saying that once it’s dried it’s completely hard and won’t leave an oily residue or transfer to your hands or clothes. Once it absorbs into the wood it will bring out the natural deep colors of the wood and preserves the look and feel without leaving a film or top coat like polyurethane or paint.
Tung oil resists water better than any other pure oil finish, does not darken or yellow with age, resists pests, is the only drying oil that completely hardens, does not go rancid or grow mold, and is FDA approved for food contact.
It should be noted that if you have a strong allergy to tree nuts, you may have a reaction to the finish. While the dried oil is food safe, the nut, seeds, oil, and leaves the tree are technically toxic and should not be ingested.
You should also beware that some products labelled as "tung oil" are actually blends containing other oils and solvents or may not contain tung oil at all. Anything other than pure tung oil will not provide the benefits listed here. It’s important to read containers carefully so you know what you’re using!
Steel and Aluminum
Steel and aluminum are obviously not natural in the sense that they are not biological, but they are minimally processed earth metals that are widely available, widely recyclable, and have amazing natural properties.
While basic steel and iron oxidize and create a layer of rust, stainless steel is an alloy containing chromium and a few other relatively common metals which reacts with the air differently to create an atomic-level film that protects the metal. Screws, plates, washers, and nuts are readily available at your local hardware store for use in your Eco Van build. While difficult to weld, it is also possible to create stainless steel frames for cabinets or tables, all of which will last longer than the van itself! It should be noted that the addition of other metals make stainless steel slightly softer than standard steel.
Aluminum is one of the most common and readily available metals on the planet and it has some amazing properties! Besides being incredibly light, it can be formed and extruded to be nearly as strong as steel and is much more flexible, which is great for use in a rolling home like a van or tiny home that bounces down the road.
It’s easily recyclable worldwide, does not conduct electricity, and has thermal properties second only to gold! Pure, polished aluminum sheeting, (like aluminum foil) can reflect 97% of radiant heat and electromagnetic radiation and only emits 3% of its stored thermal energy as radiation. In layman’s terms, when the aluminum faces an open air or vacuum space, even the thinnest layer of aluminum acts as a fantastic insulator!
Are Biodegradable Materials Bad?
This depends on your perspective, but I’d venture to suggest the answer is: No. While biodegradable materials like pine and other soft woods, wool, and cotton will not last indefinitely and may not last as long as other parts of your van, there is a strong ecological benefit to crafting a home with materials whose life cycle ends naturally.
It’s essential that you can monitor the condition of biodegradable, natural materials in your van build, so that when the time comes, you can recycle, reuse, and/or replace the material with a fresh version. This means you might not want to fill the inside of a wall with shredded denim if you can’t easily access the inside of that wall to see how it’s holding up. Using biodegradable materials also allows your van build to develop a ‘patina’ over time, allow the character and story of the material to show itself. You’re also left with the peace of mind knowing that the materials you are using won’t clog up a landfill or poison the environment for future generations.
Nothing in the natural world is permanent even though some materials will last a very, very long time. By choosing a material you know will degrade in time, you are participating in the natural cycles of life, witnessing impermanence, and being afforded the opportunity to change and evolve over time, which, is perhaps the most ecological way to build and live.