On the interior of our home, on the partition drywall walls, we used American Clay plaster. This is an amazing all natural plaster with environmental and health benefits. American Clay plaster helps maintain humidity levels around 50%-60% which is ideal for human health and for strawbale buildings (www.americanclay.com).
Clay creates a clean environment that readily absorbs moisture faster than other materials. The American Clay plaster doesn’t harm your health, but it actually helps improve it. Do you ever wonder why you feel so good when you’re outside, spending time in nature, in unaltered places, going for a hike, standing among big trees, watching waterfalls? According to the American Clay website, this plaster “maintains an incredibly dense molecular structure and shape, giving it the capacity to produce a self-generated negative charge upon hydration. Even the simple evaporation of water from clay has the capacity to produce negatively charged particles in the air. This means that when your walls breathe, or hydrate slightly with changes in humidity and slowly dry out, your interior space is being steeped in negative ions. Negative ions are proven to produce positive biochemical reactions in humans. A negative charge in a space acts on our capacity to absorb and utilize oxygen, causing us to have more energy and feel invigorated. Negative ions also have been proven to increase levels of the mood chemical serotonin, helping to alleviate depression, relieve stress, and boost our feelings of well being.” Wow, a home building product that does this. And it’s so safe to work with and easily applied.
We did some of the clay application ourselves and also hired some tradespeople to learn how to apply the American Clay so that they could offer their new skillset to clients. They remarked on more than one occasion that they could easily work long hours with this stuff because of the health benefits and the fact that it’s not harmful. They felt much better applying American Clay than applying drywall mud and finishing walls. As part of building green, it’s also incredibly important that we think about worker safety and health. So many times, homeowners unknowingly ask tradespeople and contractors to put themselves at risk, their health, their future. We need to think about that and choose products that make sense not only for the eventual inhabitant of the home but also for all those skilled workers that help create a dwelling. Paula Kiss at The Building Tree in Nelson B.C., was incredibly helpful during this stage of the project, informing, ordering products and supporting our work (www.buildingtree.ca).
We built our house with the objective to minimize electro magnetic fields, and it was great to find out that using unsealed plaster will help neutralize the electromagnetic fields. The plaster also eliminates static charge which results in clean walls that do not attract dust and also helps to filter the air of pollen and dander. There are so many health and environmental benefits to using American Clay plaster and one which results in a beautiful finished surface with an old world feel. For more information on this earth friendly product, visit www.americanclay.com
Natural Lime Plaster:
On the exterior of the house and the interior of the straw bales, we used natural hydraulic lime (NHL) plaster. We carefully considered this decision as we wanted a natural home and one that had less impact on the environment. Natural hydraullic lime plaster is a healthy product that was a perfect fit for our straw bale building. NHL plaster allows the walls to breathe at an improved rate over cement stucco (a typical finish for the exterior of straw bale building in our climate).
It is an incredibly old material, being used in ancient times, meaning it has stood the test of time and even though our home is brand new, it has an old world feel. We’re told the plaster is a finish that improves with age. Even though we are only now living with the second coat of plaster (you must do one scratch, one brown and then a final coat), it does have a warmth to it. Of the characteristcs we like, the fact that the NHL plaster has no chemical additives makes it a safe, non-toxic, natural green buildling product which is important to us.
Equally, it has the additional ecological benefit of absorbing carbon dioxide through it’s lifetime, constantly absorbing C02 as it cures. According to MichelCouvreux of TransMineral USA, “the use of lime plaster will save approximately 80% of the CO2 release compared to ordinary cement stucco. One single structure will save 10,000 lbs of CO2 emissions” (www.limes.us).
It is a suitable match for straw bale building as, “natural hydraulic lime is highly breathable, meaning condensation is able to move freely out of the straw bales—a huge benefit that greatly reduces the potential for mold growth. Natural hydraulic lime is also about 2 to 3 times more elastic than concrete, which is incredibly important when it comes to straw bale walls, because they like to settle.” (Michel Couvreux, www.limes.us)
The environmental, health and aesthetic qualities of the natural hydraulic lime plaster are benefits we really searched for when deciding to wrap our straw bales in a durable, eco friendly material.
For more information on this earth friendly product, visit www.limes.us