Current conventional design and construction practices rely on energy intensive mass-manufactured materials. Chemicals used to create conventional building materials end up in our bodies, in our soil, and in our water on a global scale. This means, to some extent, that everyone feels the impact of this harmful practice. These chemicals fill our homes and contribute to the rise of chronic conditions like asthma, diabetes, and cancer.
Bio-based materials—like straw, hemp, lime, timber, clay, and sand—are minimally processed, low in embodied carbon, and offer an alternative to the globally sourced, carbon-intensive materials commonly used in conventional construction. Naturally occurring materials are the best resources we have to create high performance buildings without a host of negative effects. Our reliance on carbon based materials and practices to build in the US has deeply impacted the health of humans, animals, and habitats all over the world. Our commitment to using bio-based materials comes from a place of compassion for people and planet.
Straw
Straw is a widely available agricultural by-product and is low in embodies carbon. Tightly packed as an insulation, it has an R value up to 2.4 per inch, outperforming most conventional insulators while also highly fire resistant.
Hemp
Hemp is low in embodied carbon, fire resistant, and has good acoustic properties and thermal performance. Hempcrete is a non-toxic bonded cellulose insulation made of hemp hurd, lime, and water. Hemp is usually grown for its fiber or seeds making the hurd an agricultural by-product. The combination of the porous structure of the hemp hurd and lime makes hempcrete resistant to mold growth by absorbing excess amounts of moisture and releasing when conditions allow.
Lime
Lime is made from crushed and heated limestone that is then slaked in water. It has been utilized as a building material all over the world for at least 9000 years. It can be used for a wide variety of applications including foundations, walls, plasters, mortars and decorative moldings. Lime has a high pH and is inherently antimicrobial and anti-fungal. Although extremely durable, it is also permeable and helps regulate humidity in a built environment.
Timber
Timber is a renewable resource that has been farmed for building materials for hundreds of years. Timber framed structures are constructed using traditional joinery and do not require the use of fasteners and adhesives. Timber can be sourced regionally preventing the need for wood sourced from around the world.
Clay
Clay is one of the oldest building materials on earth and is found in subsoils. Clay rich soils are often discarded or used as fill dirt when prepping for new builds—this makes it an abundant, inexpensive and easily locally-sourced material. Although widely extracted, clay remains abundant across the globe and even in a constructed form can be reintroduced into the biosphere with corrosion and water.
Sand
Sand is mineral granules of rocks and occurs naturally in most subsoils. As a building material, it works with binders such as clay and lime providing structure and compression strength. It can be locally sourced and made from recycled building materials.
Resources
Essential Hempcrete Construction: The Complete Step-by-Step Guide (Chris Magwood)
Essential Building Science: Understanding Energy and Moisture in High Performance House Design (Jacob Deva Racusin)
Material Cultures: Material Reform
Serious Straw Bale: A Home Construction Guide for All Climates (Paul Lacinski, Michel Bergeron)
Earthen Floors: A Modern Approach to an Ancient Practice (Sukita Reay Crimmel, James Thomson)
The Natural Plaster Book: Earth, Lime, and Gypsum Plasters for Natural Homes ( Cedar Rose Guelberth, Dan Chiras)
The Natural Paint Book (Lynn Edwards)