What is SIREWALL Insulated Rammed Earth?

Stabilized, Insulated, Rammed Earth (SIRE) walls are made using rebar and insulation enveloped with the mass of 14 – 20 inches of rammed earth. This combination, along with the SIREWALL® System for quality control and soil blending, builds walls that exceed current standards for energy efficiency and compressive strength. The SIREWALL System along with customizable forms refined over the last sixteen years by SIREWALL's expert builders, work seamlessly with unique designs and modern finishes that have timeless appeal.

SIREWALL has been the technological leader of insulated rammed earth development since its invention in 1992 and was the only practitioner for the first thirteen years. In fact, SIREWALL has a patent pending on the specific technology that leads the way in thermal and structural excellence in this emerging industry.

SIREWALL System

The SIREWALL System starts with secured reusable forms that are filled with a mixture of damp earth. The soil blend, once compacted, creates structural rammed earth walls that will last several lifetimes without the need for maintenance.

Using SIREWALL's System and ongoing advancements in technology, SIREWALL Project Managers always test soil before building, cure walls carefully, insulate with the most effective methods to ensure a continuous thermal envelope, use better retardants than those used in concrete, and tamp with mechanical tampers custom selected to optimize results.

The quality, beauty and durability of rammed earth walls are linked to the formwork used for construction. SIREWALL formwork has the flexibility of a modular system with interlocking end panels and versatile stretch panels. SIREWALL delivers predictable, cost-efficient results with minimal waste since the reusable formwork is easy to assemble and achieves consistent quality.

Ongoing Research & Development

While most people are drawn to SIREWALL by its beauty, they may not realize that this inherent beauty is actually the result of our investment in R&D. To improve functionality, the strength of Stabilized Insulated Rammed Earth needs to be so much higher than its uninsulated cousin, so we continually refine our Standards to ensure superior strength and performance. Our Standards are the highest, and we ensure SIREWALL Project Managers, professionals who are the trained more than any other in the industry, meticulously follow them.

Green Building enthusiasts inspired to break ground and build a rammed earth structure with the best of intentions may be missing key components to create healthy, energy efficient homes and buildings that will last for future generations. Here's a comparison chart that illustrates how a certain depth of experience can result in a more solid approach to rammed earth construction.

	Rammed Earth	Stabilized Rammed Earth	Non-Standard Insulated Rammed Earth	SIREWALL Stabilized Insulated Rammed Earth
Compressive Strength	1mPa - 3mPa 145psi - 435psi	3mPa - 7mPa 435psi - 1,015psi	3mPa - 28mPa 435psi - 4,060psi	10mPa - 30mPa 1,450psi - 6,000psi
R-value (insulation)	R6	R6	R12 - R29	R29 & UP
Erosion Resistance	A garden hose erodes this	Garden hose resistant	Widely variable	2,500psi pressure washer resistant
Quality Control Protocol	Unlikely	Possible	Unlikely	Yes
Risk of efflorescence	Possible	Possible	Probable	Unlikely
Curing Protocol	No	Possible	Possible	Yes
Air barrier detailing	No	No	Possible	Yes
Pre-build soil optimization	No	Unlikely	Possible	Yes
Vapour drive barrier	No	No	Unlikely	Yes
Engineer friendly	No	Yes	Unlikely	Yes
Large project capability	Possible	Possible	Unlikely	Yes
Standards & Specifications	No	Yes	Variable, Self -monitored	Yes
Possible patent infrigement	No	Yes	Yes	No

Results may vary. Matrix compares typical 2,500 square foot, two-storey home.

SIREWALL ® Cutaway

A) Rubble trench - 4 inch bed of drain rock B) Reinforced concrete footing - up to 6 feet wide C) PVC, ABS or PE drain pipe D) Interior rammed earth wall, reinforced with steel rebar E) 4" foam insulation F) Exterior rammed earth wall, reinforced with steel rebar	G) PVC or EMT pipe to function as electrical conduit H) Wooden top plate, anchored to wall, ready for roof truss I) Interior floor J) Oil or water-based acrylic sealer to prevent dusting
What's not visible in the diagram - How the strength of a stabilized, insulated rammed earth wall can vary when constructed. Depending on how a rammed earth wall is built, these factors can dramatically affect overall strength and durability: Too much or little moisture - 40% difference, best to worst Hand tamping or wrong tampers - 50% difference Curing - 50% difference Mixing - 75% difference Pneumatic tamping or wrong tampers - 25% difference Control of lift depth - 50% difference Material management - 30% difference Consistency of soils used - 25% difference The SIREWALL System uses a proven series of protocols to consistently achieve the highest possible wall strength. Download diagram PDF