FAQ
What is rammed earth?
Rammed Earth is an earth based wall system made of compacted quarried earth, normally Class 3 aggregates that are extremely strong and durable. In modern rammed earth 8-10 % cement is added as specified by an engineer. We can add rigid insulation panels within rammed earth walls for thermal resistance.
Quality rammed earth walls are dense, solid, and stone-like with great environmental benefits and superior low maintenance characteristics.
How much does it cost?
The initial cost of rammed earth construction is comparable to conventional solid masonry construction, however given the longevity of rammed earth the actual cost is considerably less in the long run. The CMHC estimates the average stick-frame home has a life span of 49 years. A properly designed rammed earth house can easily sustain its integrity for 1000+ years.
Primary factors affecting the cost of any project are design and site characteristics.
Is rammed earth suitable for a rainy climate?
Yes, it is a very suitable type of environmental building for a rainy climate. Rammed earth walls do not rot or decompose. Like any building, the most important aspects in protecting your building are the material of the wall system, roof design, strong foundation and good drainage. A well-protected rammed earth building has a much higher resistance to rain than a wood frame home or other structures made of degradable materials. Rammed earth homes routinely last for generations in many types of environments. Note our walls must be properly protected from rising damp and rain impact on the top surfaces of parapet or landscape walls.
Can the walls be painted or plastered?
Yes, if you like but it is not necessary. The walls have an organic beauty in their raw form. Most people choose to leave the walls the colour of the earth used.
What is Stabilised Rammed Earth?
Stabilised Rammed Earth is an environmentally friendly masonry wall material that looks and lasts like cut stone.
It is made from natural quarried aggregates, mixed with a small amount of stabiliser and pneumatically compacted within removable shuttering. When the formwork is removed, the walls are revealed with accurate spaces for windows, doorways, etc. already pre-formed.
What sort of ”earth” can be used?
For Stabilised Rammed Earth to achieve its optimum strength and weather resistance, it must be made from an earth that has a assortment of particles that fit together like a jigsaw without leaving voids. The sizes of the particles versus their percentages within the earth when plotted on a graph is called a “Particle Size Curve”. The ideal curve for rammed earth building has been determined from numerous laboratory tests and confirmed by years of experience on site. An ideal earth mixed with the correct amounts of stabiliser and water, then well compacted can achieve 98% density, which is virtually solid stone.
Can you use soil from the site for earth building?
No. Site soil is prone to heaving or spalling when exposed to excessive weather conditions. The impact on the immediate landscape in excavating site material is also hazardous, often creating more costs than bringing the aggregate in from a local quarry.
