| Functional unit | Production of 1 tonne of natural slate from Oppdal (12.3 m² at 30 mm thickness), natural surface with hewn or sawn edge. Covers production, transport, installation, use over 60 years, and waste management at end of life. | ||
| Service life | The reference service life is the same as for buildings and is usually set at 60 years. Natural slate has an almost unlimited service life. | ||
| ENVIRONMENTAL FIGURES PER LIFE CYCLE STAGE | (kg CO₂-eq. per tonne) | per tonne | |
| Hewn: | Sawn: | ||
| Total greenhouse gas emissions (GWP-total), Whole life cycle (A1–C4) excluding transport (A4) | 121,7 | 149,0 | |
| Production (A1–A3) | 86,0 | 109,0 | |
| Transport to construction site (A4) | 27,4 | 27,4 | |
| All production generally goes directly from Oppdal to the construction site. A transport scenario of 400 km by truck >32 tonnes is used, corresponding to the distance from Oppdal to Eastern Norway. | |||
| Installation with adhesive (A5) | 24,6 | 26,9 | |
| Slate products can be installed in various ways: loose laying (steps, slabs), with mortar, with screws, or with cement-based adhesive. A 10% material loss during installation is included. | |||
| Use phase (B1–B7) | 0 | 0 | |
| Slate is maintenance-free. It is often used untreated and typically requires no maintenance, replacement, or repair. Impregnation in kitchens and bathrooms is possible but not included in the calculations. | |||
| Demolition and waste treatment (C1–C4) | 11,1 | 11,1 | |
| It is assumed that the slate is dismantled and transported 50 km to landfill as inert waste. Reuse or recycling is not included in the calculations, but the impact from this phase is low. | |||
| Reuse/value after end of life (D) | – | – | |
| Module D is not included in the EPD, as reuse or recycling benefits are not calculated without specific assumptions. The slate in this product has, in practice, 100% reuse potential—even when laid with mortar, as long as it is not glued. | |||
| SUPPLEMENTARY ENVIRONMENTAL INDICATORS | (unit per tonne) | ||
| Hewn: | Sawn: | ||
| Primary energy use (non-renewable), Production (A1–A3) | 1050 MJ | 2190 MJ | |
| Water consumption, Production (A1–A3) | 1,53 m3 | 4,45 m3 | |
| Waste after use, Inert slate (non-hazardous waste) | 1000 kg | 1000 kg | |
| The entire product mass (1 tonne) is assumed to be sent to landfill at end of life in the scenario. This is a conservative basis in the EPD and does not reflect actual practice. Slate has very high reuse potential and is often reused in new projects. As an inert material, it does not release environmentally harmful substances and does not react with its surroundings. According to TEK17, the reuse potential of materials must be considered during planning. |
| Functional unit | Production of 1 tonne of natural slate from Oppdal (33.7 m² at 11 mm thickness), calibrated thickness with sawn edge. Covers production, transport, installation, use over 60 years, and waste management at end of life. | ||
| Service life | The reference service life is the same as for buildings and is usually set at 60 years. Natural slate has an almost unlimited service life. | ||
| ENVIRONMENTAL FIGURES PER LIFE CYCLE STAGE | (kg CO₂-eq. per tonne) | per tonne | |
| Hewn: | Sawn: | ||
| Total greenhouse gas emissions (GWP-total), Whole life cycle (A1–C4) excluding transport (A4) | 249,3 | 301,8 | |
| Production (A1–A3) | 183 | 230 | |
| Transport to construction site (A4) | 27,4 | 27,4 | |
| All production generally goes directly from Oppdal to the construction site. A transport scenario of 400 km by truck >32 tonnes is used, corresponding to the distance from Oppdal to Eastern Norway. | |||
| Installation with adhesive (A5) | 55,4 | 61 | |
| It is assumed that the slate is installed using cement-based adhesive. A 10% material loss during installation is included. | |||
| Use phase (B1–B7) | 0 | 0 | |
| Slate is maintenance-free. It is often used untreated and typically requires no maintenance, replacement, or repair. Impregnation in kitchens and bathrooms is possible but not included in the calculations. | |||
| Demolition and waste treatment (C1–C4) | 8,3 | 8,3 | |
| It is assumed that the slate is installed with cement-based adhesive and therefore must be chiseled up during demolition. After dismantling, the slate is transported 50 km and deposited as inert waste. Reuse or recycling is not included in the calculations, but the impact from this phase is low. | |||
| Reuse/value after end of life (D) | – | – | |
| Module D is not included in the EPD, as reuse or recycling benefits are not calculated without specific assumptions. The slate in this product has, in practice, 100% reuse potential—even when laid with mortar, as long as it is not glued. | |||
| SUPPLEMENTARY ENVIRONMENTAL INDICATORS | (unit per tonne) | ||
| Hewn: | Sawn: | ||
| Primary energy use (non-renewable), Production (A1–A3) | 2490 MJ | 3810 | |
| Water consumption, Production (A1–A3) | 1,02 m³ | 1,61 m³ | |
| Waste after use, Inert slate (non-hazardous waste) | 1000 kg | 1000 kg | |
| The entire product mass (1 tonne) is assumed to be sent to landfill at end of life in the scenario. This is a conservative basis in the EPD and does not reflect actual practice. Slate has very high reuse potential and is often reused in new projects. As an inert material, it does not release environmentally harmful substances and does not react with its surroundings. According to TEK17, the reuse potential of materials must be considered during planning. |
| Functional unit | Production of 1 tonne of natural slate stone from Offerdal (12.35 m² at 30 mm natural thickness and 33.67 m² at 11 mm calibrated (machine-processed) thickness) with sawn edge. Covers production, transport, installation, use for 60 years and waste handling at end of service life. | ||
| Service life | The reference service life is the same as for buildings and is usually set to 60 years. Natural slate stone has a virtually unlimited service life. | ||
| ENVIRONMENTAL DATA PER LIFE CYCLE STAGE | (kg CO₂-eq. per tonne) | per tonne | |
| Natural: | Calibrated: | ||
| Total greenhouse gas emissions (GWP-total), full life cycle (A1–C4) excluding transport (A4) | 83,3 | 144,1 | |
| Production (A1–A3) | 49,3 | 93,3 | |
| Transport to construction site (A4) | 43,9 | 43,9 | |
| All production normally goes directly from Offerdal to the construction site. The scenario assumes a distance of 650 km by truck >32 tonnes, corresponding to the distance from Offerdal to Stockholm. | |||
| Installation with adhesive (A5) | 22,9 | 39.7 | |
| Slate stone products can be installed in many ways: dry-laid (steps, slabs), with mortar, with screws, or with cement-based adhesive. A 10% material loss is assumed during installation. | |||
| Use phase (B1–B7) | 0 | 0 | |
| Slate is maintenance-free. It is often used untreated and normally requires no maintenance, replacement, or repair. Impregnation in kitchens and bathrooms is possible but not included in the calculations. | |||
| Demolition and waste handling (C1–C4) | 11,6 | 11,6 | |
| It is assumed that the slate is installed with cement-based adhesive and must therefore be chiselled up during demolition. After removal, the slate is transported 50 km and deposited as inert waste. Reuse or material recycling is not included in the calculations, but the impact from this phase is low. | |||
| Reuse/value after end of life (D) | – | – | |
| Module D is not included in the EPD, as the benefits from reuse or recycling are not calculated without specific assumptions. In practice, the slate in this product has 100% reuse potential – even when mortared, as long as it is not glued. | |||
| ADDITIONAL ENVIRONMENTAL INDICATORS | (unit per tonne) | ||
| Natural: | Calibrated: | ||
| Primary energy use (non-renewable), Production (A1–A3) | 1427 MJ | 3126 MJ | |
| Water consumption, Production (A1–A3) | 1,18 m³ | 2,79 m³ | |
| Post-use waste, inert slate (non-hazardous waste) | 1000 kg | 1000 kg | |
| The entire product mass (1 tonne) is assumed to be landfilled at the end of service life. This is a conservative assumption used in the EPD and does not reflect actual practice. Slate has a very high potential for reuse and is often reused in new projects. As an inert material, it does not release environmentally harmful substances and does not react with its surroundings. According to TEK17, the reuse potential of materials must be assessed during project planning. |
| About the comparison: | Prepared by Asplan Viak in December 2022 on behalf of Minera Skifer. Shows greenhouse gas emissions (GWP – CO₂-eq.) per m² for building materials within three common application areas: indoor flooring, outdoor paving, and façade. | ||
| Data basis: | Third-party verified EPDs from a representative manufacturer for each material. For competing materials, manufacturers have been selected as close to the project location as possible, where documented availability exists. | ||
| Functional unit: | Emissions given in kg CO₂e per m² | ||
| Timeframe: | Calculation over a 60-year lifespan | ||
| Replacement: | Included for materials with a shorter lifespan than 60 years | ||
| Transport: | All materials are assumed delivered to Oslo. Slate from Oppdal and Offerdal is assessed as delivered to Oslo or Stockholm with equivalent transport distances. | ||
| Scope: | Only the product layer (flooring, paving or façade material) is included. | ||
| Substructures and underlying layers are excluded. | |||
| Illustrations: | See below for visual representations | ||
| FLOORING – INDOOR | For natural stone, a thickness of 12 mm is used for all materials (slate, granite and marble) to ensure comparability. | kg CO₂e per m² over 60 years | |
| Offerdal quartzite | 4,5 | ||
| Solid wood flooring, pine, 30-year lifespan (1 replacement) | 4,4 | ||
| Light Oppdal quartzite | 8,3 | ||
| Granite, Portugal | 12,5 | ||
| Granite, China | 13,8 | ||
| Porcellanato, Italy | 17,4 | ||
| Parquet, 30-year lifespan (1 replacement) | 18,2 | ||
| Granite, Norway (processed in Europe) | 18,8 | ||
| Vinyl, 20-year lifespan (2 replacements) | 21,0 | ||
| Granite, Norway (processed in China) | 23,3 | ||
| Laminate, 20-year lifespan (2 replacements) | 31,0 | ||
| Marble, Italy | 75,2 | ||
| PAVING – OUTDOOR | Slate has high flexural strength and can therefore be used in thinner dimensions than other materials. For the other materials, thickness is chosen based on what is required for equivalent strength and function. | kg CO₂e per m² over 60 years | |
| Offerdal quartzite, sawn edge, t: 60 mm | 15,3 | ||
| Light Oppdal quartzite, sawn edge, t: 60 mm | 22,1 | ||
| Concrete pavers, t: 100 mm | 23,3 | ||
| Eco asphalt, t: 50 mm, 10-year lifespan (5 resurfacings) | 26,4 | ||
| Granite, Portugal, t: 100 mm | 96,8 | ||
| Granite, China, t: 100 mm | 107,6 | ||
| Granite, Norway (processed in Europe), t: 100 mm | 148,9 | ||
| FAÇADE | Slate has high flexural strength and can therefore be used in thinner dimensions than other materials. For the other materials, thickness is chosen based on what is required for equivalent strength and function. | ||
| Painted wooden cladding, incl. new coating every 10 years | 4,9 | ||
| Offerdal quartzite, sawn edge, t: 24 mm | 9,0 | ||
| Light Oppdal quartzite, sawn edge, t: 24 mm | 16,7 | ||
| Façade panel (glass fiber reinforced composite) | 18,0 | ||
| Granite, Portugal, t: 30 mm | 31,3 | ||
| Granite, China, t: 30 mm | 34,6 | ||
| Glass façade (curtain wall) | 195,0 |
| About the calculations: | Transport accounts for a significant share of greenhouse gas emissions from materials. Here you will find both a tool for calculating CO₂ emissions per transported tonne and a comparison of typical transport emissions for common building materials used in European projects. | ||
| Application: | The figures can be used both to estimate CO₂ emissions from transporting various materials and as a basis for module A4 in EPDs, LCA calculations, and assessment of local material use in projects. | ||
| Prepared by: | Asplan Viak on behalf of Minera Skifer, 2024 | ||
| Emission factor used: | 0.0685 kg CO₂e per tonne-kilometre by truck | ||
| Unit: | kg CO₂e per tonne of material, one-way | ||
| Method: | Within Europe: 100% road transport. From the rest of the world: primarily ship + 100 km truck. | ||
| Graphic: | See below for visual representations | ||
| Note: | Emissions are given per tonne of material. Lighter materials often provide more m² per tonne, but the figures still offer a good indication of the significance of transport. | ||
| REFERENCE TABLE | Used as support to estimate CO₂ emissions based on transport distance and volume. | ||
| Distance (km) | kg CO₂e per tonne | ||
| 500 | 34 | ||
| 800 | 55 | ||
| 1000 | 68 | ||
| 1500 | 103 | ||
| 2000 | 137 | ||
| 2500 | 171 | ||
| 3000 | 206 | ||
| 5000 | 342 | ||
| 7000 | 480 | ||
| 9000 | 616 | ||
| 11 000 | 754 | ||
| 13 000 | 891 | ||
| 15 000 | 1 028 | ||
| TRANSPORT EMISSIONS | |||
| for Norwegian and imported building materials | This table shows typical building materials used in Norwegian projects and their transport emissions to Oslo. The materials represent common export products from each region, and the figures provide a solid basis for early-phase comparison and material choices. Emission figures are given per tonne. | ||
| Approx. distance (km) | Country/Region | Common materials | kg CO₂e |
| 400 | Norway (Oppdal) | Slate | 27 |
| 1300 | Norway (Alta) | Slate | 89 |
| 2500 x 2 | Norway (processed in Europe) | Norwegian granite (round trip) | 686 |
| 8000 x 2 | Norway (processed in Asia) | Norwegian granite (round trip) | 1096 |
| 200 | Sweden (Bohuslän) | Granite | 14 |
| 400 | Sweden (Offerdal) | Slate | 27 |
| 500 | Sweden (Öland) | Granite | 34 |
| 1600 | Italy (Verona) | Marble, limestone | 110 |
| 1 800 | Italy (Carrara) | Marble | 123 |
| 8600 | Italy (processed imported granite) | Granite (from Brazil/India, via Italy) | 589 |
| 2 100 | Spain (Castellón, Galicia) | Ceramics, slate, granite | 144 |
| 2700 | Portugal (Lisbon, Porto) | Granite, limestone, ceramic tiles | 185 |
| 2700 | Turkey (Afyon, Isparta) | Marble, travertine, aluminium composite | 185 |
| 2800 | Germany (Saxony, Bavaria) | Fibre cement, ceramic façade panels | 192 |
| 3000 | Poland (Podkarpacie, Lublin) | HPL compact laminate, fibre cement | 205 |
| 5600 | USA (Vermont) | Marble, granite | 384 |
| 7100 | USA (Georgia) | Marble, granite | 486 |
| 7600 | India (Andhra Pradesh, Tamil Nadu) | Granite, slate, sandstone | 521 |
| 8400 | Vietnam (Thanh Hoa) | Slate, ceramic tiles | 575 |
| 8600 | China (Xiamen, Shandong) | Granite, ceramics, aluminium composite | 589 |
| 9600 | South Africa (Rustenburg) | Granite | 658 |
| 10 000 | Brazil (Espírito Santo) | Granite, solid quartzite | 685 |
| 13 800 | Australia (Perth) | Granite, ceramic façade panels | 945 |
| EPDs present environmental data based on different parameters and must be read carefully. For our products, the values are given per tonne of slate. To calculate the environmental values per square metre, use the following formula: | |
| CO₂ emissions per m² = CO₂ emissions per tonne × thickness (in meters) × density (2.7 tonnes/m³) | |
| Example: For standard slate with 30 mm thickness: | |
| 86.0 kg CO₂-equivalents per tonne × 0.030 m × 2.7 = 7.0 kg CO₂-equivalents per m² |
| The overview presents installation methods for façade, roofing, paving, walling, stairs, and slabs – all with potential for up to 100% reuse. Each method briefly describes how the slate is installed, disassembled, and stored for reuse in new projects. | |
| A more detailed description of the installation principles, with diagrams and technical explanations, is available further down the page and as a downloadable PDF. | |
| FAÇADE | |
| Horizontal with hook | |
| Horizontal/vertical with screws | |
| Dowel anchoring | |
| Expansion anchors | |
| . | |
| OUTDOOR PAVING | |
| Laid in loose aggregates | |
| On pedestals (raised floor system) | |
| . | |
| ROOFING | |
| Flagstone roof | |
| Square slate roof | |
| . | |
| WALLING | |
| Machine-laid wall | |
| Double wall | |
| . | |
| STAIRS | |
| Terrain steps in loose fill | |
| Slate treads on pedestals and rails | |
| . | |
| SLABS | |
| Dot-glued or laid on substrate |
| TECHNICAL PERFORMANCE AND DURABILITY | |
| Expected lifespan: | Oppdal and Offerdal quartzite have a documented lifespan of 100 years or more – even in exposed outdoor environments. No replacement needed under normal use. |
| Frost resistance: | 100% frost-resistant. No risk of cracking from moisture or temperature fluctuations. Suitable for both inland and coastal climates. |
| UV resistance: | Does not lose color, gloss, or surface quality over time. Withstands direct sun and weather without visible aging. |
| Surface/wear resistance: | Very high. Slate withstands heavy mechanical use without losing function or appearance – also in public environments and high-traffic areas. |
| . | |
| OPERATION AND MAINTENANCE | |
| Maintenance needs: | Minimal. Only mechanical cleaning is recommended (sweeping, water, pressure washer, or brush). No need for chemicals, oil, or sealants. |
| Typical maintenance frequency: | Outdoors: approx. every 5–10 years. Indoors (dry use): as needed. Façades: can remain untouched for decades. |
| Biological growth (algae/moss): | Some growth may occur in damp and shaded areas. Easily removed mechanically or with suitable cleaning agent. Not harmful to the slate. |
| . | |
| ENVIRONMENT AND COMPARISON | |
| Effect on environmental accounting: | Long lifespan results in low emissions per year. Lifespan affects module B4–B5 in LCA and reduces the product’s GWP per functional year. |
| Comparison with alternative materials: | Many alternative materials (e.g. wood, fiber cement, tiles) have a lifespan of 20–40 years and require regular maintenance or replacement. |
| . | |
| AGING AND AESTHETIC DEVELOPMENT | |
| Aging process: | Slate can develop a natural patina in the form of lighter tones, veils, or spots. Influenced by light, moisture, and surroundings. The change is visual and limited to the surface. |
| Material performance after aging: | The slate remains technically unchanged. Density, strength, and frost resistance are not affected. |
| Aesthetic value over time: | Slate ages with character and provides a timeless, calm appearance. Suitable for projects where natural aging is appreciated as part of the architecture. |
| Design expectations: | Changes over time should be accepted as part of the material’s expression. For projects with strict visual requirements, the patina and degree of change should be considered in the material selection. |
Relevant regulations and guidance:
Level(s) – European framework for sustainable buildings
EU-wide system for assessing and reporting on the environmental performance of buildings. Provides structure and common language for circular design, LCA and sustainability documentation – especially useful in large-scale projects.
EU Taxonomy – Sustainable construction and real estate
Defines criteria for classifying construction projects as environmentally sustainable. Emphasises low embodied emissions, energy efficiency, circular economy, and product documentation through EPDs.
Construction Products Regulation (CPR) – Regulation (EU) No 305/2011
Lays down harmonised rules for marketing construction products in the EU. Requires performance documentation including environmental characteristics and suitability for reuse and recycling.
EN 15804 – Environmental Product Declarations for construction products
European standard that defines the core rules for EPDs of construction products. Widely used across Europe for LCA-based sustainability assessments and material comparisons.
Construction and Demolition Waste – EU rules & best practices
EU guidance on managing construction and demolition waste in a resource-efficient manner. Includes recycling targets, protocols for selective demolition, and circular economy measures.
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