mineral / Glass / Glass Products
Glass Block System
Structural glass blocks for partition walls and decorative elements with thermal and acoustic insulation properties
Atlas code
MIN-GLA-PRO-005
At-a-glance signals
Structural glass blocks for partition walls and decorative elements with thermal and acoustic insulation properties
Overview
Executive summary
Glass blocks (also known as glass bricks) are hollow or solid translucent masonry units manufactured from pressed and fused soda-lime glass, used to construct non-loadbearing or semi-structural walls, partitions, and infill panels that admit natural daylight while providing privacy, thermal insulation, and sound attenuation. Standard hollow glass blocks consist of two pressed half-shells fused together at high temperature (~800 degC), creating an enclosed air cavity that provides insulating properties. Standard block sizes are 190x190x80mm and 240x240x80mm, with larger formats also available. Glass blocks are laid in mortar or proprietary channel systems with reinforcement, similar to conventional masonry. In Australian construction, glass blocks are primarily used for commercial and residential feature walls, bathroom partitions, stairwell enclosures, and facade elements where light transmission with privacy is required. Fire-rated glass block systems are available achieving 45, 60, or 90-minute FRL ratings when installed with compliant framing and mortar systems.
Best when…
- Excellent natural daylighting while maintaining visual privacy
- Good thermal insulation for a glazing product (U-value 1.1-2.8 W/m2K)
- Strong sound insulation (STC 35-53 depending on type)
- Non-combustible with fire-rated options up to 90 minutes
- Durable and low maintenance - glass surface resists staining and weathering
- Wide range of patterns, colours, and finishes for design flexibility
- Vandal and graffiti resistant (glass surface easily cleaned)
- Suitable for wet areas - impervious to moisture
Top advantages
- 01 Excellent natural daylighting while maintaining visual privacy
- 02 Good thermal insulation for a glazing product (U-value 1.1-2.8 W/m2K)
- 03 Strong sound insulation (STC 35-53 depending on type)
- 04 Non-combustible with fire-rated options up to 90 minutes
- 05 Durable and low maintenance - glass surface resists staining and weathering
Top limitations
- 01 Heavy self-weight (60-80 kg/m2) requiring adequate structural support
- 02 Cannot carry structural loads beyond self-weight and in-plane loads
- 03 No ventilation capacity - fixed glazing only
- 04 High installed cost compared to conventional glazing or masonry
- 05 Limited to non-loadbearing or infill panel applications
Technical
Physical ·9
- Density
- 2400-2500 kg/m3 Soda-lime glass density. Wall assembly density is lower due to hollow core. Assembled wall ~60-80 kg/m2. Source: Wikipedia Glass brick, glass material properties
- Specific gravity
- 2.4-2.5 Soda-lime glass
- Porosity
- 0 % Glass is non-porous. Mortar joints have some porosity
- Water absorption
- 0 % Glass is impervious to water. Mortar joints may absorb moisture
- Hardness
- 5.5-6.5 Mohs Soda-lime glass hardness. Surface is scratch-resistant
- UV resistance
- Moderate-Good Glass transmits UV to varying degrees depending on composition. Standard soda-lime glass blocks approximately 90% of UVB but transmits most UVA. Some blocks available with UV-filtering coatings
- Chemical resistance
- Excellent Excellent resistance to most chemicals, acids, and cleaning agents. Only hydrofluoric acid and strong alkalis at high temperature attack glass
- pH tolerance
- 1-12 pH Glass is resistant to most acids except hydrofluoric acid. Alkaline solutions can etch glass over time
- Surface roughness
- 1-50 um Smooth glass surface. Textured/patterned faces have controlled roughness for light diffusion
Mechanical ·7
- Tensile strength
- 30-50 MPa Soda-lime glass tensile strength. Actual block strength lower due to surface flaws and stress concentrations at fused seam
- Compressive strength
- 6-45 MPa Standard hollow glass blocks ~6-7 MPa per EN 1051-1. Aerogel-filled research blocks ~45 MPa. Solid blocks significantly higher. Source: ScienceDirect 2023, EN 1051-1
- Flexural strength
- 30-50 MPa Individual glass block flexural strength. Wall panel flexural capacity depends on reinforcement and mortar
- Shear strength
- 5-15 MPa Glass block wall shear capacity depends on mortar joint strength and reinforcement. Individual block shear strength per EN 1051-1
- Poisson's ratio
- 0.22-0.24 Soda-lime glass
- Impact resistance
- Moderate-High J Glass blocks resist moderate impact. Solid blocks (Vistabrik) are vandal and bullet resistant. Standard hollow blocks can crack from heavy impact but typically do not shatter dangerously
- Creep resistance
- Excellent Glass does not creep at ambient temperatures. Mortar joints may exhibit minor creep under sustained load
Sustainability & Health
Embodied carbon & energy ·7
- Embodied carbon
- 0.70-1.20 kg CO2-eq/kg Glass manufacturing is energy-intensive (~1500 degC melting). Embodied carbon for soda-lime glass ~0.86 kg CO2-eq/kg (ICE database). Glass blocks have higher embodied carbon per m2 due to thickness and mass. Source: University of Bath ICE database, Vitro EPD, AGC data
- Carbon footprint
- 50-100 kg CO2-eq/m2 Per m2 of glass block wall (~80 kg glass/m2). High due to energy-intensive manufacture and material mass. Standard glass ~6.64 kg CO2-eq/m2 per 4mm thickness (Saint-Gobain). Glass blocks ~80mm thick = substantially more. Source: Saint-Gobain ORAE EPD, AGC data, industry estimates
- Embodied energy
- 12-18 MJ/kg Energy-intensive manufacturing. Glass melting at ~1500 degC consumes significant energy. Recycled cullet reduces energy by ~25%. Source: ICE database, glass industry EPDs
- Water footprint
- 5-15 L/kg Water used in glass manufacturing for cooling and cleaning. Moderate water consumption
- Recycled content
- 15-50 % Glass blocks can incorporate recycled cullet. Industry moving toward >50% recycled content. Seves Glassblock uses recycled glass in production. Source: AGC, Saint-Gobain sustainability data
- Renewable content
- 0 % No renewable content - 100% mineral composition (silica, soda ash, dolomite)
- Circular score
- 5.0 /10 Glass is 100% recyclable but glass blocks are difficult to separate from mortar for recycling. Typically downcycled as aggregate. Long lifespan reduces replacement frequency
Compliance & Fire
Fire performance ·6
- Combustibility class
- A1 Glass is non-combustible. Classified A1 per EN 13501-1 (no contribution to fire). Passes AS 1530.1 non-combustibility test
- Fire resistance level
- 0-90 minutes Standard hollow blocks provide no rated fire resistance. Fire-rated glass blocks: 45, 60, and 90-minute UL-classified assemblies available. 60-min units in masonry or framed walls, 90-min units in steel-framed window openings only. Source: Innovate Building Solutions
- Ignition temp
- N/A - non-combustible degC Glass does not ignite - inorganic material
- Flame spread index
- 0 Zero flame spread - non-combustible material
- Smoke dev. index
- 0 Zero smoke development - non-combustible inorganic material
- Heat release rate
- 0 kW/m2 Zero heat release - glass is inorganic non-combustible material
Cost & Lifecycle
Capex & lead time ·6
- Material cost (range)
- 150-500 AUD/m2 Supply only. Based on ~25 blocks per m2 (190x190mm) at $15-35 per block. Fire-rated blocks significantly more expensive. Source: Glass Block Constructions Perth, Matt Turner QS ($55.42/block for framed kit)
- Material cost (per unit)
- 15-55 AUD/block Per standard 190x190x80mm block. Clear/basic patterns at lower end, coloured/specialty at upper. Source: Glass Block Constructions, industry estimates
- Lead time
- 7-60 days Standard patterns typically stocked by Australian suppliers. Specialty colours, patterns, or fire-rated blocks may require import (6-12 weeks)
- Lifecycle cost
- 300-700 AUD/m2 High initial cost offset by very low maintenance and long lifespan. Glass blocks rarely need replacement
- Annual maintenance
- 1.00-5.00 AUD/m2/year Very low - periodic cleaning and occasional mortar joint inspection/repair
- Market availability
- Moderate Specialist product with limited but established Australian supply chain. Glass Block Constructions (Perth), importers in Sydney and Melbourne. Most products imported from Europe (Seves/Vetroarredo, Italy)
Service life & durability ·3
- Expected lifespan
- 50-100+ years Glass blocks are extremely durable. Many installations from the 1930s-40s remain in service. Mortar joints may need repointing every 30-50 years
- Maintenance interval
- 5-10 years Periodic cleaning and inspection of mortar joints. Glass surface requires minimal maintenance. Check sealant at perimeter joints every 5-10 years
- Warranty period
- 10-25 years Manufacturer warranties vary. Seves Glassblock offers product quality guarantees. Glass is inherently durable with no degradation over time
Layer D
Where it's used
Interior partition walls
Bathroom and wet area walls
Facade feature panels
Stairwell and corridor daylighting
Fire-rated assemblies