MATERIAL DATA SHEET

Earth Brick - Stabilized

Earth/Clay
mineral › Clay-Based › Earth/Clay
mineralclay-basedearthcompressed-earth-blockCSEBCEBstabilisedcement-stabilisedsustainablelow-embodied-energythermal-massfire-resistantnon-combustibleowner-builder
ATLAS CODE
MIN-CLY-ETH-002
Earth Brick - Stabilized
Category mineral
Material Family Clay-Based
Regulatory Status Non-combustible (by performance)
Density
1700-2100 kg/m3
Carbon (A1-A5)
0.03-0.08 kg CO2-eq/kg
Fire Class
Non-combustible (by performance)
Lifespan
100+ years
Description

Compressed stabilised earth blocks (CSEB) made from subsoil, sand, and a small percentage of cement or lime (typically 4-8%), mechanically compressed at high pressure (approximately 21 MPa / 3000 psi) to produce dense, durable masonry units. Unlike traditional adobe, CSEBs achieve higher compressive strength (5-10+ MPa), improved water resistance, and consistent dimensional accuracy through mechanical pressing. The stabilising agent (Portland cement, lime, or combinations) creates a permanent chemical bond that resists moisture penetration and weathering. Blocks are cured (not fired) for 28 days, using approximately 1/5 to 1/15 the energy of fired clay bricks. In Australia, CSEB construction is governed by HB 195-2002 (The Australian Earth Building Handbook) published by Standards Australia, with NCC compliance typically achieved through performance solutions. CSIRO fire testing has demonstrated 4-hour fire resistance ratings for 250 mm earth block walls. Australian manufacturers include Compressed Earth Bricks Australia (CEBA) and Mudtec, with blocks tested for erosion resistance and compressive strength per HB 195.

Primary Sectors
[Residential]
Typical Uses
  • Residential load-bearing walls
  • Bushfire-zone construction
  • Sustainable housing projects
  • Garden and landscape walls
290140mm
Primary Form [290 / X / 140 / X / 90 / Mm / (common)]
Weight [5-10] kg/block
Recycled Content 0-50
Renewable Content 0-2
Recyclability 80-95
Embodied Carbon 0.03-0.08 kg CO2-eq/kg
Embodied Energy 0.5-1.5 MJ/kg
EPD Available No
Advantages
Significantly improved durability and water resistance compared to traditional adobe through cement/lime stabilisation.CSIRO-tested fire resistance: 4-hour rating for 250 mm walls — excellent bushfire zone performance.Uses only 10% of the energy of fired bricks — approximately 50-70% lower embodied carbon than conventional masonry.High compressive strength (5-10+ MPa) comparable to medium-quality fired bricks, suitable for load-bearing construction.Integrated walling system — load-bearing CSEB walls eliminate need for separate framing, cladding, and insulation in appropriate climates.
Cautions
NCC compliance requires performance solutions — not covered by deemed-to-satisfy provisions in most jurisdictions.Requires specialised pressing equipment (manual or hydraulic CEB press) for production.Cement stabilisation increases embodied carbon compared to unstabilised adobe, though still much lower than fired bricks.Thermal insulation (R-value) is low — additional insulation typically required to meet NCC energy efficiency requirements.Limited mainstream market acceptance in Australia — specialist builders and engineers required.
TECHNICAL DATA: PERFORMANCE PROPERTIES MIN-CLY-ETH-002
Density (Dry) 1700-2100 kg/m3
Specific Gravity 1.7-2.1
Porosity 15-30 %
Water Absorption 5-15 %
Hardness 3-5 Mohs
Surface Roughness 100-1000 um
UV Resistance good
Chemical Resistance moderate
pH Tolerance 6-12 pH
Available Colors
Natural earth tones — varies with local soil typeRed/ochre soils — warm red-brownGrey/dark soils — charcoal to dark brownSandy soils — cream to buffOxide pigments can be added for colour variationRendered and painted — any colour
Surface Finishes
Exposed face brick (machine-pressed)Lime render (breathable, traditional finish)Cement render (higher durability)Lime wash (simple protective coating)Earth plaster (matching clay-based finish)Clear sealant (consolidates surface, maintains natural appearance)
Texture Options
Machine-pressed smooth faceTextured face (from mould patterns)Rendered (lime or cement render)Lime-washedNatural exposed earth surface
Pattern Options
Standard running bondStack bondExposed face (natural earth colour and texture)Interlocking patterns (proprietary block systems)Rendered (smooth or textured finish)Feature walls with contrasting soil colours
Compressive Strength 5-10 MPa
Tensile Strength 0.3-1.0 MPa
Flexural Strength 1.0-2.5 MPa
Shear Strength 0.3-1.0 MPa
Elastic Modulus 1.0-5.0 GPa
Yield Strength Not applicable MPa
Impact Resistance moderate J/m
Bearing Capacity Not specified kPa
Poisson's Ratio 0.15-0.25
Creep Resistance moderate
Abrasion Resistance Moderate-Good
Thermal Conductivity 0.35-0.80 W/mK
Thermal Resistance 0.50 m2K/W
Specific Heat Capacity 900-1000 J/kgK
Thermal Expansion 5-10 x10^-6/degC
Melting Point Not applicable (vitrifies >900) degC
Ignition Temperature Not applicable degC
Sound Transmission Class (STC) 48-55 Rw
Noise Reduction Coeff. (NRC) 0.05-0.10
Optical
Light Transmittance 0 %
Light Reflectance (LRV) 20-50 %
Solar Reflectance (SRI) 15-40

Compressed earth block technology originated in the 1950s with the development of the CINVA-Ram manual press in Colombia by Raul Ramirez. This simple lever-operated press made it possible to produce consistent, high-density earth blocks without firing, opening up earth construction to systematic, repeatable building practices. The technology spread globally through development agencies and was adopted across Africa, Asia, South America, and Australia. In Australia, CSIRO conducted significant research into earth block construction in the 1970s-1980s, including fire resistance testing that demonstrated 4-hour ratings. Standards Australia published HB 195-2002 (The Australian Earth Building Handbook) to provide formal guidance. Modern developments include hydraulic and motorised presses achieving higher pressures and production rates, interlocking block systems that eliminate mortar requirements, optimised soil-cement ratios for improved strength and durability, and alternative stabilisers (geopolymers, lime-pozzolan, rice husk ash) to reduce Portland cement content and embodied carbon. The Auroville Earth Institute in India has been a global leader in CSEB research and training since the 1980s. In Australia, companies like CEBA and Mudtec now produce commercially available blocks with consistent quality assurance.

SAFETY, ECOLOGY & INSTALLATION MIN-CLY-ETH-002
Flame Spread Index 0
Smoke Developed Index 0
Combustibility Class Non-combustible (by performance)
Ignition Temperature Not applicable degC
Fire Resistance Rating 221-240 (CSIRO tested) FRL (minutes)
Heat Release Rate 0 kW/m2
Toxicity of Combustion non-toxic
Embodied Carbon (A1-A3) 0.03-0.08 kg CO2-eq/kg
Embodied Energy 0.5-1.5 MJ/kg
Water Footprint 30-80 L/kg
EPD Available No
Recycled Content 50%
Renewable Content 2%
LEED Points 3-6 points
Circular Economy Score 8.5 /10
VOC Emissions 0 ug/m3
Skill Level semi-skilled to skilled
Crew Size 2-4 persons
Installation Time 5-10 m2/day
Curing Time 28 days
Setting Time 4-24 hours
Temperature Range 5-35 degC
Humidity Range 30-70 %RH
Required Tools
CEB press (manual lever, hydraulic, or motorised)Soil screening/sieving equipmentConcrete mixer (for soil-cement mixing)Spirit level and string lineTrowel (for mortar joints, if not interlocking system)Rubber mallet (for block placement and adjustment)Moisture testing equipment (for optimal pressing moisture)Wheelbarrow and shovel
Certifications Required
No specific trade certification for CSEB construction in AustraliaStructural engineer assessment required for load-bearing walls (HB 195 or performance solution)Building permit required — performance solution typically needed for NCC complianceGeneral construction induction (White Card) for commercial sitesManufacturer training recommended (CEBA offers workshops)
Weather Limitations
Do not lay blocks or press blocks in rainProtect fresh walls and curing blocks from rainAvoid construction in freezing conditions (cement mortar hydration)Cover completed wall tops during construction to prevent water ingress
COMMERCIAL, LOGISTICS & REGULATORY MIN-CLY-ETH-002
Material Cost 15-80 AUD/m2
Installation Cost 80-400 AUD/m2
Annual Maintenance 1.00-5.00 AUD/m2/year
Lifecycle Cost (50yr) 200-500 AUD/m2
Market Availability limited-moderate
Lead Time 4-8 weeks
Supply & Logistics
Shelf Life Indefinite once cured — cement stabilisation provides permanent durability. Blocks continue to gain strength over time. months
Design Life 100+ years
Warranty Period 10-25 years
Maintenance Interval 5-10 years
Service Temp Range -10 to 60 degC
Freeze/Thaw Resistance 50-150 cycles
Dimensional Stability 0.5-1.5 mm/m
Certifications Held
CEBA batch testing per HB 195 — compressive strength and erosion resistanceIndividual manufacturer quality assurance programs
Fire Code Compliance
Performance solution required — earth blocks not listed in NCC deemed-to-satisfy provisionsCSIRO fire testing: 250 mm wall = 4-hour FRL; 150 mm wall = 3 hours 41 minutesNon-combustible by performance — inorganic earth and cement composition
Standards Compliance
NCC Volume 2 — Class 1 and 10 buildings (residential) — performance solution pathwayHB 195-2002 provides accepted design methodology referenced by building surveyorsMinimum wall thickness 200 mm per HB 195Structural engineer sign-off required for load-bearing applicationsTreated as full masonry construction for engineering and design purposes

DISCLAIMER: This specification document is generated from the CLAD Materials Atlas Database. Information is for general guidance only and does not constitute professional engineering advice. Values are typical and may vary by batch, manufacturer, and production run. Verify suitability for specific project applications independently.

ID: MIN-CLY-ETH-002 Schema: v3.0