Block · Sizes pending
Clay-Based — indicative fig. M·41
Fire A1 Non-combustibleEmbodied carbon 0.01kgCO₂e/kg LowCompressive 2-8MPa StructuralDesign life 30yr
Unfired clay brick made from earth, clay, sand, and organic matter for traditional sustainable construction
01 Physical
Density 1500-1900kg/m3
Specific gravity 1.5-1.9
Porosity 20-40%
Water absorption 10-25%
Hardness 1.5-3Mohs
UV resistance good
Chemical resistance poor
pH tolerance 6-9pH
Surface roughness 500-5000um
02 Mechanical
Tensile strength 0.1-0.5MPa
Compressive strength 2-8MPa
Flexural strength 0.3-1.8MPa
Shear strength 0.1-0.5MPa
Poisson's ratio 0.15-0.25
Impact resistance low
Creep resistance moderate
03 Thermal
Thermal conductivity 0.40-0.60W/mK
Specific heat 900-1000J/kgK
Thermal expansion 5-8x10^-6/degC
04 Compliance & Fire First question
Combustibility class Non-combustible (by performance)
Fire resistance level 120-240 (estimated, performance solution required)FRL (minutes)
Ignition temp Not applicabledegC
Flame spread index 0
Smoke dev. index 0
Heat release rate 0kW/m2
05 Sustainability & Health
Embodied carbon 0.01-0.05kg CO2-eq/kg
Carbon footprint 5-25kg CO2-eq/m2
Embodied energy 0.5-2.0MJ/kg
Water footprint 50-100L/kg
Recyclability 100%
Recycled content 0-100%
Renewable content 1-4%
Circular score 9.5/10
VOC emissions 0ug/m3
Toxicity rating non-toxic
LEED contribution 3-6points
06 Durability · Cost · Logistics
Expected lifespan 30-100+years
Maintenance interval 1-5years
Warranty period Not applicableyears
Material cost (range) 5-120AUD/m2
Material cost (per unit) 2-8AUD/brick
Lead time 2-6weeks
Lifecycle cost 200-500AUD/m2
Annual maintenance 3.00-10.00AUD/m2/year
Market availability limited
07 Assessment
Advantages
- Extremely low embodied energy — materials sourced locally (often from the building site), sun-dried with minimal processing energy.
- Excellent thermal mass — 300 mm walls provide outstanding diurnal temperature moderation in Australian climates.
- Fire resistant — unfired earth is non-combustible and provides excellent fire resistance performance.
- Fully recyclable and biodegradable — earth bricks can be returned to the soil at end of life with zero waste.
- Healthy indoor environment — earth walls regulate humidity naturally and contain no VOCs, formaldehyde, or synthetic chemicals.
Constraints
- Highly vulnerable to moisture damage — driving rain, rising damp, and flooding can cause erosion and structural failure without protective measures.
- Low insulation value (high thermal mass but low R-value) — additional insulation typically required to meet NCC energy efficiency requirements.
- NCC compliance is complex — typically requires performance solutions assessed by qualified engineers rather than deemed-to-satisfy provisions.
- Labour-intensive manufacture and construction — slow build process limits commercial viability without owner-builder participation.
- Variable material properties — soil composition, mixing quality, and curing conditions create inconsistent brick strength and durability.
08 Applications
A1 Residential load-bearing walls Load-bearing mud brick walls for 1-2 storey residential construction. Typically 300 mm thick with mud mortar joints. Performance solution required for NCC compliance.
A2 Thermal mass walls (passive solar design) Internal or external thermal mass walls for passive solar heating and cooling. High thermal mass of 300 mm walls moderates diurnal temperature swings.
A3 Infill walls in timber frame Non-load-bearing mud brick infill panels within a timber post-and-beam structural frame. Simpler structural assessment than load-bearing applications.
A4 Garden and landscape walls Non-structural garden walls, retaining walls, and landscape features. Must be protected from moisture with copings and good drainage.
09 Sources & Standards
Sources pending — citations for this material are not yet recorded. Verify all figures against manufacturer data and current standards before specifying.