Block · 390 × 190 × 190 mm
Cementitious — indicative fig. M·20
Fire A1 Non-combustibleEmbodied carbon 0.12kgCO₂e/kg LowCompressive >=15MPa StructuralDesign life 100yr Durable
390 x 190 x 190 mm hollow lightweight CMU (Adbri Litec 200 series). Unit weight ~12.2 kg; f'uc ≥ 15 MPa; thermal conductivity ~0.35–0.55 W/mK; fire insulation 120 min (hollow non-loadbearing) to 240 min (solid/grouted loadbearing). Complies with AS/NZS 4455.1 and AS 3700.
01 Physical
Density 1200–1500kg/m3
Specific gravity 1.2–1.6
Porosity 20–35%
Water absorption 8–12% by mass
Hardness 4–5 (approx)Mohs
UV resistance Excellent (inherent UV stability)
Chemical resistance Good (non-aggressive environments); Fair (coastal, sulphate-bearing soils)
pH tolerance 6–13 (service); 12.5–13.5 (internal pore solution)pH
Surface roughness 200–800um
02 Mechanical
Tensile strength 1.0–1.8 (estimated)MPa
Compressive strength >=15MPa
Flexural strength 0.2–0.5MPa
Shear strength 0.15–0.25MPa
Poisson's ratio 0.15–0.20
Impact resistance Moderate
Creep resistance Moderate — higher creep than normal-weight CMU; movement joints recommended at floor levels
03 Thermal
Thermal conductivity 0.35–0.55 (hollow); 0.50–0.70 (grouted)W/mK
Specific heat 840–1000J/kgK
Thermal expansion 7–9x10^-6/C
04 Compliance & Fire First question
Combustibility class Non-combustible (AS 1530.1 / NCC Group 1)
Fire resistance level FRL –/120/120 (hollow non-loadbearing) to 240/240/240 (grouted loadbearing)minutes
Flame spread index 0
Smoke dev. index 0
Heat release rate 0kW/m2
05 Sustainability & Health
Embodied carbon 0.12
Carbon footprint 125
Embodied energy 1.5MJ/kg
Water footprint 180L/kg
Recyclability 100%
Recycled content 30%
Renewable content 0%
Circular score 7
VOC emissions 0
Toxicity rating Non-toxic (in service); respiratory hazard (cutting dust — P2 mask required)
LEED contribution 3
06 Durability · Cost · Logistics
Expected lifespan 100
Maintenance interval 7
Warranty period 10
Material cost (range) $5–10 per block (trade, AUD, 2025)
Material cost (per unit) $55–90 per m2 (blocks only, AUD, 2025)
Lead time 1–5 days
Lifecycle cost $350–550 per m2 over 50 years (AUD)
Annual maintenance $1.5–4 per m2 per year (AUD)
Market availability Widely available in eastern Australia
07 Assessment
Advantages
- 25–30% lighter than equivalent normal-weight CMU (unit weight ~12.2 kg vs ~16–18 kg), reducing bricklayer fatigue and manual handling injury risk.
- Significantly improved thermal performance — effective thermal conductivity ~0.35–0.55 W/mK versus ~0.8–1.2 W/mK for normal-weight CMU, reducing heating and cooling loads.
- Non-combustible mineral composition; achieves fire resistance ratings to FRL 240/240/240 (loadbearing, grouted) under AS 1530.4 and AS 3700.
- Manufactured with lightweight industrial by-products (expanded clay, slag), incorporating recycled/waste streams and reducing virgin material consumption.
- Compatible with standard 400 x 200 mm masonry module — direct dimensional substitution for normal-weight CMU with no design coordination changes.
- Accepts N12/N16 reinforcement in hollow cores; can be fully grouted for reinforced masonry construction under AS 3700.
- Hollow-core geometry reduces material use and self-weight while cores can be used as service conduit channels before grouting.
- Complies with AS/NZS 4455.1 Exposure durability grade, suitable for sheltered to partially exposed above-ground applications without surface treatment.
- Durable 100-year service life expectancy in normal above-ground environments with low maintenance once rendered or painted.
- Broadly available through Adbri Masonry distribution network across eastern Australia; standard stock item at major building suppliers.
Constraints
- Lower compressive strength than normal-weight CMU at equivalent density — standard lightweight CMU typically achieves 5–10 MPa, limiting loadbearing height without fully grouted or reinforced construction.
- Higher water absorption (8–12% by mass) compared to normal-weight CMU (~5–8%), requiring sealing or render to resist moisture ingress in exposed locations.
- More brittle and susceptible to chipping during handling and cutting; saw cutting preferred over hammer splitting to avoid block damage.
- Porous surface requires priming or bonding agent before direct tiling, and may absorb excessive moisture from mortar coats if not pre-wetted.
- Premium price over standard CMU — typically 15–30% more expensive per block due to the cost of lightweight aggregate processing.
- Lighter unit weight reduces acoustic mass; unrendered lightweight CMU walls achieve lower STC ratings than equivalent normal-weight walls and may require additional lining layers.
- Lightweight aggregate can be susceptible to freeze-thaw cycling in alpine or wet climates if not adequately protected by render or paint.
08 Applications
A1 Loadbearing external walls (residential, 1–3 storeys) 190 mm lightweight CMU used for loadbearing external walls in Class 1/2 residential buildings. Weight saving reduces footing loads and improves bricklayer productivity. Render finish provides weatherproofing.
A2 Non-loadbearing fire-compartment walls FRL –/120/120 to –/240/240 achievable for hollow non-loadbearing Litec 200 walls, making them suitable for fire compartmentation in commercial and multi-residential buildings.
A3 Rendered external walls (commercial) 190 mm lightweight CMU wall with 2-coat sand-cement render and acrylic paint, used as thermally improved, fire-rated external skin for commercial buildings.
A4 Internal separating walls (Class 2 apartments) 190 mm rendered lightweight CMU meets Rw + Ctr ≥ 45 dB NCC acoustic separation requirement between dwellings. Non-combustible construction satisfies NCC fire separation requirements.
A5 Acoustic barrier walls (transport noise) Single-leaf 190 mm lightweight CMU used for road noise barriers and boundary walls adjacent to transport corridors. Render both sides for Rw 48–52 dB attenuation.
A6 Reinforced retaining walls (≤1.8 m height) 190 mm lightweight CMU with vertical reinforcement in grouted cores and geotechnical design, used for garden retaining walls and site terracing up to 1.8 m height.
A7 Bushfire-prone area construction (BAL-FZ) Non-combustible masonry external wall system qualifying for all BAL levels including BAL-FZ. No combustible wall components; render or paint finish maintains compliance.
A8 Commercial and industrial loadbearing walls Lightweight CMU walls for warehouses, factories, and commercial buildings where reduced dead load is advantageous for slab-on-ground and tilt-up panel combinations.
A9 Boundary and fence walls Freestanding boundary walls using 190 mm lightweight CMU with pier posts and capping. Lighter blocks reduce footing requirements and labour effort versus normal-weight CMU.
A10 Energy-efficient residential construction (NCC Section J) Lightweight CMU walls as the primary thermal mass element in residential construction. Improved k value (0.35–0.55 W/mK) over normal CMU assists NCC 2022 Section J compliance with minimal added insulation in CZ 1–3.
09 Sources & Standards
Sources pending — citations for this material are not yet recorded. Verify all figures against manufacturer data and current standards before specifying.