A revolutionary building system for the creation of High Mass Earthen Walls, An innovative technology for an age-old process.
The earth-building industry witnessed an initial revolution about 20 years ago when Architect and Builder, Michael Frerking, entered “POURED EARTH” (PE) into the lexicon of earthen technologies. This was because Poured Earth – a more earth-friendly soil cement material – could now be poured like concrete, thereby taking full advantage of both the existing infrastructure of the concrete industry and its readily available forming systems. But, unlike concrete, the Poured Earth mixture designed by Living Systems replaces most of the Portland cement that is typically used in concrete with more earth-friendly binders (like fly-ash, a waste-stream product). The result is a sizable reduction in the amount of carbon dioxide produced. (The concrete industry is responsible for 7% of the carbon dioxide released around the world every year due to its use of Portland cement!) With the addition of colored oxides, these high-mass, low maintenance walls beautifully reflect the varying earthen tones of the site. Today Living Systems offers an even more innovative – and affordable – method for the construction of high-mass earthen walls called “FORM FREE.” Like Living Systems’ original method of pouring its earth-friendly soil cement (Poured Earth,) this system can be pumped quickly. It also takes advantage of the concrete industry’s delivery infrastructure. However, unlike the original PE method, the patent-pending FORM FREE process now eliminates the need for expensive, heavy, labor-intensive forms! The result: EASE of CONSTRUCTION and AFFORDABILITY!
An In-depth look at the FORM FREE method
A “Bending Machine” – invented by LSSA for the easy manufacture of these forms – takes a roll of 1”x1” mesh at one end of the table and unrolls it “backwards” to the other end of the 12′ table in order to make it flat. At that point, a shear cuts the correct length and a sheet metal brake bends the material precisely where needed. The “forms” are constructed so that they can easily be folded flat for delivery. But, before they are folded, insulating foam is inserted and stabilized in the center of the “forms.” Electrical conduit and hydronic tubing for radiant heating and cooling are then attached to the foam. This is all done in the shop before delivery of the forms to the site.
Once delivered to the construction site the “forms” are bolted to the foundation. They are then joined together using lightweight stainless steel aviation cable. In essence, they are simply “stitched” together! Once the forms are secured to the foundation and to each other, the “walls” are ready to be poured with an earth-friendly soil cement mixture that is specifically designed to work with the Form Free method of construction. This mixture replaces a large portion of the Portland cement (responsible for 7% of global warming) with lime and synthetic fly-ash (thereby repurposing an otherwise discarded by-product from the burning of coal.) The mixture can also be made with natural fly-ash if and when the synthetic is no longer available. Using a concrete truck to deliver the material, it is then pumped into the walls. As the mixture fills the forms, it extrudes about 1” through the mesh and is then quickly ready to be troweled smooth. Color can be added to the mixture using oxides before it leaves the concrete batch plant or sprayed on after the walls are poured. The latter allows color to take on a more interesting and varied look at much less expense.
Here are a few process photos, click the images to enlarge…
FAQs about Poured Earth
What is the difference between Poured Earth and concrete and why is PE a more earth friendly building material?
Naturally occurring, unprocessed soils usually contain clay, which the concrete industry historically considers the “enemy” as it weakens a concrete mix. The clay, therefore, must be washed out which is both water intensive and costly. Otherwise, Poured Earth, rammed earth and concrete mixes have a similar granular composition. Poured Earth and rammed earth, however, use a much wider variation of soils – including clay – making it possible to use minimally processed on-site soils.
All these mixes are defined by aggregate which ranges from sand and silt to rock up to 3/4” diameter. Another important common factor is that the aggregate is packed tightly to allow the binder to act effectively. Imagine a jar of marbles that you can reach deep down into to pull out a marble near the bottom. Now add sand to this jar and shake up the mix and try the same thing. You can’t get the marble out very easily because the space between the marbles has now been filled with sand and the marbles no longer easily slide by each other. This is what a binder does in both concrete and PE.
Poured Earth also allows the use of on-site materials. Just as we are able harvest on-site resources such as the sun, wind and rain for our sustainable building purposes, Poured Earth gives us the opportunity to thoughtfully use site soils to build walls, floors, interior plasters, and even roof systems.
By using on site resources we minimize and/or eliminate the need for energy-intensive foreign oil products that are trucked across the nation and around the world. Using sustainable, local materials grows the local economy by maintaining and creating more “green” jobs.
Properly designed “high mass” Poured Earth homes minimize, and can potentially eliminate, the energy required for home heating and cooling. This is because the “mass” acts much like a battery – a highly durable energy storage system – but one that is able to last for hundreds of years. (For more information on “high mass,“Why Build High Mass Walls?”at end of Design/Build page.)
Poured Earth also minimizes the use of energy intensive Portland cement by reducing and potentially replacing it with synthetic and/or natural sources of low to no energy-use materials use such as fly-ash. Synthetic fly-ash is a bi-product of the coal industry that, for many years, was simply discarded. The use of synthetic fly-ash in Poured Earth, therefore, can be seen as providing a green “bridge” until newer, more sustainable binders become more cost effective and readily available.
Magnesium oxide (MgO) is another important way to replace Portland cement as a binder. If MgO is used, then Poured Earth actually becomes a net minus building product!!! This is because unlike Portland cement, which is a major contributor to global warming, MgO actually sequesters more carbon than it uses in its production. Hence, the carbon footprint is net minus! At this point in time MgO is more expensive than synthetic fly-ash so synthetic fly-ash tends to be the choice of most clients. But, the MgO alternative is available.
Why is Poured Earth less expensive ….even rivaling the cost of frame construction?
There are five important reasons.
1. The Form Free System reduces time and labor which reduces the cost of construction.
With the introduction of the patent-pending Form Free Wall Building System, there is no longer a need for the heavy, labor-intensive aluminum or wood forms originally used for the construction of the high-mass PE walls. Specifically, they reduce labor time and cost because they do not need to be erected, removed, cleaned, loaded onto a truck and, finally, stocked and stored. Rather, the “forms” used in the Form Free process are a fraction of the weight so they are easily created, transported and erected on site. Moreover, because they are internal, there are no residual cleaning, transporting or storage issues! The result? EASE of CONSTRUCTION and AFFORDABILITY.
2. Passive heating & cooling is “free” which saves energy and money today… and over time!
With all the savings that follow from the creation of high mass walls, the cost is now absolutely comparable to SIP, ICF and other alternative wall building materials available today. This is because high mass PE walls provide the passive heating and cooling system for the home or building. That is, it creates a system that is “free,” because it requires only heat from the sun or cool from the evening! For an in-depth explanation of how high mass walls work to heat and cool a building, see the FAQ page on High Mass. It is also important to remember that this is a savings that will continue into the future making the choice to build high mass walls over frame an even better decision as energy costs continue to climb! These walls are also inflammable!!!
3. Thoughtful architectural design reduces building costs by up to 20%
Living Systems excels in architectural design. Its goal is to design only the amount of space necessary to achieve the client’s needs. The result is a more efficient use of space that does not compromise the overall sense of spaciousness normally associated with larger homes. This process easily reduces building costs by 10-20%. Living Systems’ goal is to improve building quality and reduce future maintenance without expanding the budget.
4. The cost of a long-term investment is priceless!!
While we have been trained to think of cost within the context of a short-term return on investment (often 12 months or less), this way of thinking fails to look at the long-term return on investment that often produces the better profit. A quality, energy-efficient home that is healthy and comfortable will last for generations. As the ad says: the price of health, comfort and energy savings……PRICELESS.”
5. Poured Earth walls require little to no maintenance!
Poured earth walls require no to very little maintenance. This can amount to a lot of money over time. Frame, as well as other forms of wall construction, often need maintenance within the first few years. We all know that wood is abused by the sun in the southwest and rain in other parts of the country can lead to the deterioration of other kinds of walls. Poured Earth walls, on the other hand, are not bothered by sun or rain! They are made to last for generations.
Let us Help You Build with Poured Earth!
Living Systems is led by architect Micahel Frerking who specializes in a revolutionary building technique called Form Free Poured Earth. We offer sustainable architecture services including Design/Build and consulting, and provide Poured Earth Training and Certification. Please feel free to contact us if you would like to learn more or start a conversation about your next project.