FastLCA is a free, browser-based tool for calculating the Global Warming Potential (GWP) of construction materials and assemblies across their full life cycle. This page explains the methodology, data sources, system boundaries, and limitations so you can judge whether the results are appropriate for your use.
Embodied carbon refers to the greenhouse gas (GHG) emissions associated with the manufacture, transport, construction, maintenance, and end-of-life of building materials — everything except the energy used to operate the building.
It is measured as Global Warming Potential (GWP), expressed in kg CO₂ equivalent (kg CO₂e) — converting all greenhouse gases (CO₂, CH₄, N₂O, etc.) to a single comparable unit using their 100-year warming potential.
As operational energy efficiency improves, embodied carbon is becoming a larger share of a building's total lifetime emissions — often 40–80% in well-insulated buildings. The Architecture 2030 challenge and RICS/RIBA whole-life carbon targets both require embodied carbon to be tracked and reduced.
FastLCA scope: A1–A3 (product stage) + A4–A5 (construction) + C1–C4 (end of life) + Module D (beyond boundary, reported separately). Use phase B1–B7 is not included — it requires project-specific service life data beyond the scope of a generic calculator.
FastLCA follows the modular life cycle structure defined in EN 15804+A2:2019 — the European standard for environmental product declarations (EPDs) for construction products.
Raw material extraction (A1), transport to factory (A2), and manufacturing (A3). This is the primary focus of most EPDs and generic databases. Usually the largest contributor — often 70–90% of total A1–C4 for most materials.
Transport to site (A4) using user-specified distance and vehicle type. Site energy use and waste factor (A5). Defaults are illustrative — enter project-specific values for accuracy.
Maintenance, repair, replacement, and operational energy/water. Not included — these require project-specific service life assumptions outside the scope of a generic material-level calculator.
Demolition (C1), waste transport (C2), processing (C3), and disposal (C4). FastLCA uses generic per-kg estimates by material category and EOL scenario. For EPD products with declared C1–C4, those values are used directly.
The potential benefit from reuse, recycling, or energy recovery beyond the building's life cycle. Per EN 15804+A2:2019 clause 6.4.3.4, Module D is always reported separately and never added to the A1–C4 total. FastLCA strictly follows this rule. Module D = 0 for landfill is correct — no recovery means no credit.
The generic material database in FastLCA uses emission factors from the Environmental Performance in Construction (EPiC) Database 2024, published by the University of Melbourne under a CC BY-NC-ND 4.0 licence — Attribution, NonCommercial, NoDerivatives. FastLCA uses EPiC values as internal calculation inputs only; raw data values are not exported or redistributed.
CC BY-NC-ND 4.0 — creativecommons.org/licenses/by-nc-nd/4.0/
FastLCA uses EPiC Database 2024 values as internal calculation inputs only. In compliance with the CC BY-NC-ND 4.0 licence:
EPiC uses a hybrid life cycle inventory (LCI) approach, combining:
This means EPiC values are systematically higher than process-only databases like EU EPDs. The difference is real — EPiC is capturing emissions that exist in the supply chain but are excluded from process-only methods due to system boundary truncation.
⚠ EPiC is based on Australian manufacturing conditions. Values reflect Australian energy grids, transport distances, and production processes. For European or UK projects, treat EPiC values as upper-bound indicative estimates and replace with European EPDs (IBU, EPD Norway, Environdec) where formal accuracy is required.
| Material | EPiC 2024 value | Unit | Typical EU EPD range | Note |
|---|---|---|---|---|
| Concrete 25 MPa | 0.153 | kg CO₂e/kg | 0.10–0.16 | 368 kg CO₂e/m³ ÷ 2400 kg/m³ |
| Concrete 40 MPa | 0.207 | kg CO₂e/kg | 0.14–0.22 | 497 kg CO₂e/m³ ÷ 2400 kg/m³ |
| Reinforcing steel (bar) | 2.10 | kg CO₂e/kg | 0.5–2.5 (EAF vs BF) | Steel bar direct value; hot rolled sections = 2.90 |
| Aluminium extruded | 29.40 | kg CO₂e/kg | 6–12 (EU recycled content avg) | Primary production; EPiC captures full global supply chain |
| Sawn softwood (kiln-dried) | 1.215 | kg CO₂e/kg | 0.2–0.5 | 583 kg CO₂e/m³ ÷ 480 kg/m³; hybrid captures processing chain |
| Glulam (indoor) | 3.436 | kg CO₂e/kg | 0.4–1.0 | 1718 kg CO₂e/m³ ÷ 500 kg/m³; adhesives included in hybrid |
| Glass wool insulation | 4.00 | kg CO₂e/kg | 1.0–2.0 | Direct EPiC value; melting energy-intensive |
| EPS/XPS insulation | 8.00 | kg CO₂e/kg | 3.0–5.0 | EPiC combines EPS and XPS; petrochemical feedstock included |
| Polyurethane rigid foam | 17.50 | kg CO₂e/kg | 4.0–8.0 | MDI/polyol feedstocks energy-intensive; hybrid captures full chain |
| Float glass | 2.00 | kg CO₂e/kg | 0.8–1.5 | Direct EPiC value; high-temp melting process |
| Clay brick | 0.32 | kg CO₂e/kg | 0.20–0.35 | Direct EPiC value; consistent with EU ranges |
| Portland cement | 1.30 | kg CO₂e/kg | 0.70–0.90 | Direct EPiC value; higher than EU avg due to Australian grid |
For greater accuracy, FastLCA allows users to enter product-specific Environmental Product Declarations (EPDs) from verified sources. These override the generic EPiC values for that material.
EPDs are third-party verified declarations produced by manufacturers in accordance with EN 15804 and ISO 14025. They provide GWP values specific to a named product and manufacturing facility, typically with tighter system boundaries than hybrid databases.
FastLCA does not pre-load manufacturer EPDs to avoid serving outdated or incorrect data. Instead, users can find current EPDs from:
| Database | Coverage | URL |
|---|---|---|
| EPD Hub | EU aggregator — best starting point | epdhub.com |
| EPD Norway | Nordic / EU — excellent for insulation, timber, windows | epd-norge.no |
| IBU | Germany / EU — very thorough EN 15804 compliance | ibu-epd.com |
| Environdec | Global — thousands of verified EPDs | environdec.com |
| EC3 | North America — large, free database | buildingtransparency.org/ec3 |
| BRE Global | UK — BREEAM verified EPDs | breeam.com |
FastLCA performs a simplified streamlined LCA. The core calculation for each material is straightforward:
Source: ECTA (2011) European transport emission factors. Vehicle options: heavy truck >32t (0.096 kg CO₂e/t·km), medium truck (0.114), light van (0.227), rail (0.024), sea (0.016).
Source: IEA (2023). Options include EU average (0.233 kg CO₂e/kWh), Nordic grid (0.193), Estonian grid (0.112), global average (0.450), diesel generator (0.202), and renewable (0).
For generic EPiC materials, FastLCA uses per-kg C1–C4 factors estimated from published EPD ranges by material category and end-of-life scenario (landfill, incineration + energy recovery, recycling, reuse/deconstruction). These are indicative estimates, not values from a single verified source. For EPD products that explicitly declare C1–C4, those declared values are used directly.
⚠ FastLCA is not a certified LCA tool and does not produce certified EPDs. Results are indicative estimates suitable for early-stage design decisions, material comparisons, and educational purposes. They should not be used for regulatory compliance, planning applications, or formal procurement criteria without review by a certified LCA practitioner.
| FastLCA is suitable for | FastLCA is not suitable for |
|---|---|
| Early-stage design comparisons — is CLT or concrete lower carbon for this wall? | Formal LCA reports for BREEAM, LEED, or planning requirements |
| Hotspot identification — which material dominates embodied carbon? | EPD or Environmental Product Declaration production |
| Sensitivity testing — what if we use recycled steel instead of virgin? | Regulatory submissions or legal compliance claims |
| Education and learning about embodied carbon principles | Claims about a specific manufacturer's product performance |
| Client presentations showing indicative carbon estimates | Projects where Australian-specific EPiC values would be misleading for European material specifications |
| Standard / Source | Role in FastLCA |
|---|---|
| EN 15804+A2:2019 | Life cycle module structure (A1–D), system boundary rules, Module D reporting convention |
| ISO 14040:2006 | General LCA methodology principles and framework |
| ISO 14044:2006 | LCA requirements and guidelines |
| EPiC Database 2024 — Crawford, Stephan & Prideaux, University of Melbourne | All generic A1–A3 emission factors. CC BY-NC-ND 4.0. DOI: 10.26188/10257728.v11 |
| ECTA (2011) | Transport emission factors for A4 (kg CO₂e per tonne·km by vehicle type) |
| IEA (2023) | Electricity grid carbon intensities for A5 site energy calculation |
FastLCA was built to fill a gap: most free embodied carbon tools are either too simple (a single number with no transparency) or too complex (requiring training to use). FastLCA aims to be transparent about its methodology, honest about its limitations, and useful enough to support real early-stage decisions.
The tool is maintained as a personal project. The generic database (EPiC 2024) is openly licensed. All calculation logic runs in your browser — no data leaves your device except feedback you choose to submit.
Corrections, feedback, and EPD suggestions are welcome at [email protected] or via the feedback button in the calculator.
For formal LCA work: FastLCA is a screening tool. For certified LCA reports, EPD production, or regulatory compliance, engage a certified LCA practitioner and use a fully validated LCA software platform (SimaPro, OpenLCA, One Click LCA, etc.).