MATERIAL DATA SHEET

Welsh slate roofing

Metamorphic Stone
mineral › Stone › Metamorphic Stone
mineralstonemetamorphicroofingheritagepremiumWelshtraditional
ATLAS CODE
MIN-STN-MET-003
Welsh slate roofing
Category mineral
Material Family Stone
Regulatory Status Non-combustible to AS 3959
Density
2700 kg/m³
Carbon (A1-A5)
157 kgCO2e/m²
Fire Class
Non-combustible to AS 3959
Lifespan
100 years
Description

Welsh slate is a fine-grained metamorphic rock formed over 500 million years ago in Wales. Renowned for its durability, low porosity, and distinctive grey-blue color, it remains the premium roofing material for high-end residential and heritage projects. The material offers exceptional weather resistance, minimal maintenance requirements, and a lifespan exceeding 100 years when properly installed.

Primary Sectors
[Residential][Institutional]
Typical Uses
  • Heritage building restoration
  • Premium residential roofing
  • Churches and cathedrals
  • Government buildings
  • Luxury homes
  • Traditional architecture
  • Conservation projects
Renewable Content 0
Recyclability 100
Embodied Carbon 157 kgCO2e/m²
Embodied Energy 1 MJ/kg
EPD Available No
Advantages
Exceptional durability (100+ years)Very low water absorptionDistinctive aestheticMinimal maintenanceFire resistantWeather resistantTraditional craftsmanship
Cautions
High cost due to importSkilled installation requiredHeavy weightLimited supplyLong lead timesSpecialist tools needed
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TECHNICAL DATA: PERFORMANCE PROPERTIES MIN-STN-MET-003
Density (Dry) 2700 kg/m³
Specific Gravity 2.7
Porosity 0.5 %
Water Absorption 0.35 %
Hardness 3.5
UV Resistance Excellent - Natural stone, no UV degradation
Chemical Resistance Excellent - Resistant to acid rain, salt spray
Compressive Strength 150 MPa
Tensile Strength 12 MPa
Flexural Strength 50 MPa
Elastic Modulus 60 GPa
Impact Resistance Good - varies with thickness J/m
Abrasion Resistance Excellent
Thermal Conductivity 1.49 W/(m·K)
Thermal Resistance 0.0067 m²·K/W
Specific Heat Capacity 810 J/(kg·K)
Thermal Expansion 0.0000075 /°C
Melting Point 1200 °C
Ignition Temperature N/A - Non-combustible °C

Slate has been used as roofing material for centuries. Welsh Penrhyn slate arrived in Australia as ship ballast in the early 1800s and remains functional after 150+ years. Spanish slate introduction occurred 15-20 years ago. AS 4597-1999 standardised installation requirements, reconfirmed in 2015.

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SAFETY, ECOLOGY & INSTALLATION MIN-STN-MET-003
Flame Spread Index 0
Smoke Developed Index 0
Combustibility Class Non-combustible to AS 3959
Ignition Temperature N/A - Non-combustible °C
Fire Resistance Rating Non-combustible hours
Embodied Carbon (A1-A3) 157 kgCO2e/m²
Embodied Energy 1 MJ/kg
EPD Available No
Renewable Content 0%
Circular Economy Score 85 /100
VOC Emissions 0 g/L
Skill Level Professional slater required
Crew Size 2-4 persons
Installation Time 1 m²/person/day
Temperature Range 5-40 °C
Required Tools
Slate ripperSlate hammerSlate cutterNail gun
Certifications Required
Licensed roof tilerWorking at heights
Weather Limitations
No installation in rainWind speed <40km/h
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COMMERCIAL, LOGISTICS & REGULATORY MIN-STN-MET-003
Material Cost 130 – 150 $/m²
Installation Cost 70 – 350 $/m²
Annual Maintenance 0.5 $/m²/year
Lifecycle Cost (50yr) 3.5 $/m²/year
Market Availability Readily available - Import required
Lead Time 6 weeks
Design Life 100 years
Warranty Period 30 years
Maintenance Interval 5 years
Service Temp Range -40 to 80 °C
Freeze/Thaw Resistance Excellent - <0.4% water absorption
Dimensional Stability Excellent - Minimal thermal movement
Certifications Held
CE Marking (imported slate)Low embodied carbonNon-toxic natural material
Fire Code Compliance
AS 3959-2018 (BAL-12.5 to BAL-FZ)
Standards Compliance
NCC 2022 Volume Two Part 3.5.2ASTM C406ASTM C120ASTM C121ISO 14025 (EPD methodology)EN 12326-1EN 12326-2

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-STN-MET-003 Schema: v3.0
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