Rammed earth is an ancient method of building. The rammed earth method uses wooden forms that are placed and secured, then damp earth with 10% cement is loaded into them and tamped to total compaction. When the forms are removed, the wall is complete.

External walls are a minimum of 300mm in thickness which enables them to be load bearing. Internal walls can be reduced in thickness to 200mm but are not load bearing at this size.

Traditionally, rammed earth walls used clay as the only glue holding the compacted soil together. But today, rammed earth construction uses some cement along with the dirt. The ratio of cement to earth depends on several factors, including the clay content of the dirt and the complexity of the building. We find that 10% cement makes for a strong earth wall. Like cement, rammed earth walls get stronger as they age.

In locations with limited building area the thick earth walls will reduce the available living space, although in Perth, rammed earth houses are regularly built on small city lots. There is some cement in the walls. Cement has a high-embodied energy. The impacts of the small amount that we use are amortized over hundreds of years.

All hard, massive materials are similar in that they are hard and massive: stone, brick, adobe, cob, concrete, concrete block. What sets them apart is what they are made of and how they perform. Building a house out of concrete is like cutting butter with a chainsaw. The strength is way beyond what is required. Also concrete is a very brittle material. Rammed earth has about half the compressive strength of concrete and it's still twice as much as is required.

Yes, we can. That is, if you are building with our SIREwall system. We have an experienced team of designer/builders who know their way around rammed earth design.

Yes. We recommend that you bury the north-facing side of a rammed earth home, and have your windows on the south-facing side. Rammed earth works extremely well in an earth-bermed home.Click for more information about how Terra Firma's earth walls suit earth-berming.

Essentially, the colour of the wall is determined by the colour of the local dirt. Many people feel that their house blends well with its natural surroundings when the walls are the colour of the local dirt. You can vary this considerably using iron oxides. We have found that the warm tones, of browns and reds work well. We have even done "mocha" coloured walls. Some clients have chosen to create a sedimentary look with different oxide tints in different layers.

by David Easton - an inspirational guide complete with history, design, soil selection, forming, ramming and details by N. America's best-known rammed earth builder. by Bruce King, P.E. - a small book very useful for understanding how engineers think about rammed earth. by Hugo Houben and Hubert Guillaud - far and away the most complete and technical book on its subject. by David Easton - an earlier book by David, which is not as big or detailed but very reader-friendly. No.

SRE Walls are constructed utilising a quality road base material (soil and gravel mixture) stabilised with cement.

Well-designed passive solar homes coupled with the high thermal mass of the walls, enables them to naturally store energy (warm or cool) creating a stable internal temperature for the dwelling.

Generally it is, but design, aesthetics and budget determine whether earth is placed above door and window openings. A minimum height of 300mm above the opening is required.

No, rammed earth walls are built with soil tamped into forms similar to poured concrete.  CEB is more similar to brick construction with individual units; where as rammed earth is more similar to solid concrete walls.  Like CEBs, rammed earth walls use clay/sand soils.  We build with CEBs because we find them to be more user- friendly and easier to make structural alterations and remodels with. A CEB cavity wall system also offers several insulating options.  Back to Top

Poured earth is a method of earth construction in which formwork is prepared to cast a wall in-situ. The earth material is prepared by mixing with a cement stabilizer (Formblock recommends at least 10% cement), and water to slump similar to that of most concrete mixes, and simply poured in the moulds and allowed to set. Formblock is different to rammed earth as the earth is not required to be pounded or ramming as part of the procedure.

Adobe Builder Magazine & Southwest Adobe School P.O. Box 153 Bosque, NM 87006 http://www.adobebuilder.com The Rammed Earth House by David Easton His company is Rammed Earth Works located in California http://www.rammedearthworks.com The Earth Building Foundation - A resource of printed information, school, and networking. http://www.earthbuilding.com Home Page What We Do About Rammed Earth Photo Gallery Published Articles Testimonials Awards FAQ's Land Sales Contact Us

We were initially drawn to rammed earth for environmental reasons. Five acres of land can only provide enough lumber for twenty houses, whereas a five-acre pit can provide enough earth for the walls of five thousand homes. We now believe that rammed earth can do just about everything better than wood-frame. The most obvious attribute of the rammed earth is the design flexibility and the opportunity for creative exterior and interior finishes.

We tried to create a sand-blasted texture on the earth walls with a 3,500 psi pressure washer. The kind of pressure washer you can cut a 2x4 with. We blasted the walls for a long time and it scarcely changed the wall surface at all. The walls are extremely hard. Our engineer says a SIREwall? home, built with appropriate roof overhangs, and good drainage should last 1,000 years or more.

We do not offer rammed earth how-to courses for the general public. We do offer weekend courses for people interested in rammed earth to find out more. And we will be offering training to builders who buy SIREwall franchises. Email us with your name and we'll keep you up to date on these options.

Absolutely. A rammed earth interior wall is useful for creating a sound separation within the home and for additional thermal mass.

high as the engineer and the budget allows us to. In seismic areas, we can build two stories, and in non-seismic areas probably more. We have built many rammed earth walls 18 ft. high. There's a cost premium to building second floor rammed earth.

You can put any roof you want on rammed earth. There are no limitations. If you want to collect drinking water from your roof, then metal or glass is best. If you want to shield yourself from radio waves and microwaves, then choose a heavy roof with clay or concrete. If you are concerned about the environment, you could choose recycled rubber tire roofing.

Just like any other house, you can have a basement. Structurally, it's no problem. But we don't recommend basements or crawlspaces that are outside of the main building thermal envelope. Our main problem with uninsulated basements or crawlspaces has to do with indoor air quality. It's impossible to keep an unheated underground space from becoming damp, especially on the wet west coast of Canada.

The dirt used in rammed earth is one of the most abundant materials on the planet. The "right stuff" contains absolutely no topsoil or organics. It has a minimal amount of silt and 5-20% clay. The rest is, at best, an even mix of sand and gravel with particle sizes up to 2 inches. We've spent a good deal of time developing an efficient formwork technology. Unlike rammed earth forms in California and Australia, the SIREwall? form system doesn't require any through-ties.

Load bearing rammed earth walls can support roof structures as well as second storey floors. This eliminates the need for structural timber or metal posts, and reduces the building time and cost.

Yes! SRE walls compliment any décor from rustic to modern design; they are as timeless as the earth itself and will not date.

SRE walls are non-combustible and have a high fire rating (4 hours) making them extremely suitable for dwelling in high fire risk areas.

Due to the materials and construction method, SRE walls are deemed 'termite resistant' under the Building Code of Australia. When built on a concrete slab, termite protection is required only around pipe work penetrating the slab area, reducing costs associated with termite proofing a dwelling.

Yes! We combine knowledge from a site inspection as well as a brief from you outlining your likes and dislikes, needs and project budget. This enables us to design an affordable passive solar home that meets your needs and blends in with the surroundings and environment.

No, standard council planning and building permits apply. If purchasing land, ensure that there are no caveats attached to the title restricting the construction of a rammed earth dwelling.

We have come to the conclusion that it's very risky to try the SIREwall™ system of insulated rammed earth without Terra Firma's expertise. At a minimum, the design should be overseen and approved by Terra Firma. As well, during the wall building, at least one Terra Firma expert needs to be on site at all times. Very often owners work along with us and are integrally involved in the designing and building of their rammed earth home.