14 Oct 2023
Natural building is an environmentally sustainable method of construction that relies on natural materials like earth, stone, and wood rather than industrial products.
Natural building is an environmentally sustainable method of construction that relies on natural materials like earth, stone, and wood rather than industrial products. This ancient building technique has seen a revival in recent years as more people seek greener and healthier alternatives to conventional buildings.
In this article, we'll provide an overview of the basics of natural building. We'll cover the common materials used, the benefits of this approach, the techniques involved, examples of natural structures, and some of the movement's leading proponents.
Whether you're an architect looking to incorporate more ecological practices or a homeowner interested in a natural home, read on to learn the fundamentals of this green building method.
Materials Used in Natural Building
Natural builders harness materials available in the local landscape rather than using manufactured products that require high energy inputs to produce. Some of the main materials used include:
Adobe (bricks made of clay, sand, and straw)
Rammed earth (compressed earth into forms)
Cob (mixture of clay, sand, straw, and water)
Wattle and daub (woven sticks with earthen plaster)
Earth is extremely versatile and provides the bulk of mass for thick earthen walls that regulate interior temperature and humidity. Clay has binding properties, while sand prevents cracking. Straw adds tensile strength.
Wood is used for structural frameworks as well as finishes and detailing. Locally harvested woods like acacia and eucalyptus are common in natural building.
Stone can be used structurally or decoratively. Flat stones are often employed in flooring. Rounded river stones add aesthetic appeal.
Other common materials include thatch, wool, hempcrete (hemp blended with lime), and earthen plasters made of clay, sand, and natural pigments. Choosing locally sourced, renewable materials drastically reduces the embodied energy of a building.
Benefits of Natural Building
Natural building offers many advantages over conventional construction:
Sustainable: It relies on abundantly available local materials rather than extracted and manufactured products.
Energy efficient: Earthen and stone walls provide effective insulation, regulating interior temperatures and reducing the need for heating and cooling.
Healthy indoor air: Natural materials allow good airflow and humidity regulation while avoiding off-gassing from synthetic products. This creates excellent indoor air quality.
Durability: Earth and stone structures can last for centuries with proper maintenance. Adobe pueblos in New Mexico have stood for hundreds of years.
Aesthetically pleasing: Natural materials offer unique beauty and charm with handcrafted imperfections that create a warm, organic feel.
Cost effective: Simple techniques reduce construction costs compared to modern buildings. Homeowners may further save on utilities.
Ecologically friendly: Natural building has a small carbon footprint with minimal waste. It also promotes conservation of local resources.
With so many benefits, it's easy to see why natural building is growing in popularity around the world. The sustainable qualities and natural aesthetics have wide appeal.
Natural Building Techniques
While each material requires specialized techniques, natural building incorporates a range of common practices:
Rubble trench foundations filled with stone
Pierre à terre walls of layered stones and earth
Raised pole foundations to protect wood framing from moisture
Foundations must be designed to handle the load-bearing weight of earthen walls and prevent erosion. Rubble trenches distribute weight and provide drainage.
Stacked stone and boulder walls
Interlocking cob shaped by hand into monolithic walls
Adobe bricks bound with earthen mortar
Light clay infill within timber frames
Wattle and daub weaving
Wall systems employ natural materials structurally for enclosure, insulation, and thermal mass. Forms are temporary while earthen walls are self-supporting when complete.
Thatched roofs of straw or reeds
Living roofs with soil and plants
Timber rafters and beams with earthen tiles
Vaulted and domed stone roofs
Roofing protects the interior from sun, rain, and wind. Thatched roofs insulate well while living roofs integrate with the natural landscape. Wood and stone roofs lend support.
Tamped earthen floors
Stone or clay tile flooring
Wood plank flooring
Flagstone or pebble mosaic floors
Floors utilize materials at hand like earth, stone, clay, and wood. Tamped earth is a simple base while tiles and wood create more durable finished flooring.
Clay slip plasters for earthen walls
Lime plaster with natural pigments and shells
Earthen plasters reinforced with plant fibers
Plasters provide a protective surface layer over wall systems and create aesthetic appeal. Locally available clays, lime, and plant fibers are employed.
Getting the right proportions of clay, sand, and fibers is an art that develops over time. Generations of builders have passed on time-tested techniques for crafting durable earthen structures.
Examples of Natural Buildings
Natural building techniques can be adapted to create beautiful and functional homes and structures. Some examples include:
Cob cottages with thatched roofs, earthen plasters, and large timber elements
Courtyard-style adobe homes and guest houses surrounding shared outdoor space
Timber framed structures infilled with light clay or wattle and daub
Stone and earthen commercial buildings such as studios, offices, and multi-use spaces
Outdoor earthen ovens for cooking and baking
Agricultural buildings like barns constructed from local wood and earth
By employing native materials, these buildings tie into local architectural heritage while updating vernacular styles. The diversity of natural homes showcases creative solutions adapted to climate, materials, culture, and needs.
Proponents of the Natural Building Movement
The natural building revival has been championed by several influential activists and builders. Some of the leading proponents include:
Ianto Evans, who pioneered the revival of cob building in the Pacific Northwest in the 1970s
Michael Reynolds, creator of the Earthship sustainable home model using earth-rammed tires
Joseph Kennedy, founder of the Cob Cottage Company, which builds small cob homes
Carrie Coburn, author of books on earthen plasters and natural building techniques for women
Jacquelyn Ogorchock, who teaches hands-on natural building workshops around the world
Through their writing, teaching, and building projects, these individuals have helped spur interest in traditional methods of ecological construction using the earth itself as a building material.
Natural building taps into vernacular construction methods perfected over centuries. By utilizing local and natural materials, it provides an ecological alternative to modern building. With proper design and technique, natural homes can be beautiful, functional, and lasting.
This ancient craft continues evolving with new applications and materials like hempcrete and living roofs. If you're interested in green building, natural construction allows working in harmony with the environment to create healthy and sustainable architecture.