The ICE Database (Inventory of Carbon & Energy) is an open dataset of embodied-carbon and embodied-energy values for construction materials, compiled by Circular Ecology (Hammond & Jones). For most materials it expresses embodied carbon as kg CO₂e per kg of material — a per-kilogram intensity you can use to compare options early, before a formal assessment. It’s one of the most widely used reference datasets for ICE Database embodied carbon work, and it’s a foundation for fast, indicative comparison rather than certified reporting.
This guide is for practitioners: architects, engineers, developers, and sustainability consultants who already know what embodied carbon is and want to use ICE values well, without overreading them.
The short version
- The ICE Database gives embodied-carbon values, mostly in kg CO₂e/kg, for ~1,600+ construction materials.
- Values are generic, regional/sector averages — useful for early comparison, not project-specific or certified.
- Most figures are cradle-to-gate (extraction to factory gate), a narrower boundary than whole-life carbon.
- Read values as ordinal signals: timber low, concrete moderate, primary aluminium high.
- Check the licence before you build ICE into a workflow: Circular Ecology does not permit its use in software tools, and from 30 September 2026 not for non-educational use.
- Elementa no longer uses ICE. It prices each layer from a pinned ÖKOBAUDAT generic dataset (A1–A3) and shows indicative impact classes per m³ — not an EPD or LCA.
What is the ICE Database?
The ICE Database is an open, freely available embodied-carbon dataset compiled by Circular Ecology (Hammond & Jones), widely used across the construction sector as a starting reference for material carbon. It collates published values from many sources into one consistent table, so practitioners can look up a material and get a defensible “first number” without commissioning bespoke data.
It matters because embodied carbon is becoming the carbon conversation. As operational energy decarbonises, embodied (upfront) carbon becomes a larger share of whole-life carbon (World Green Building Council, “Bringing Embodied Carbon Upfront”, 2019). The buildings and construction sector already accounts for ~37% of global energy- and process-related CO₂ emissions (UNEP, Global Status Report for Buildings and Construction 2025-2026). A shared, open reference like ICE lets teams reason about material choices long before a certified assessment exists.
The database covers a broad span: metals, concrete and cement, masonry, timber and wood products, insulation, plastics, glass, and more. That breadth is exactly why it’s useful at the sketch stage, when you’re choosing between material families rather than specifying a product.
What does “embodied carbon, kg CO₂e/kg” actually mean?
It means the greenhouse-gas emissions associated with producing one kilogram of a material, expressed in carbon-dioxide equivalent. “CO₂e” rolls several gases (CO₂, methane, and others) into a single figure weighted by warming effect. So a value of, say, “X kg CO₂e/kg” reads as: every kilogram of this material carries X kilograms of CO₂-equivalent emissions from its production.
Per-kilogram is the key. To get a material’s contribution to a building, you multiply its intensity by the mass you’re using, not its volume or area. That’s where intuition can mislead: a dense material with a modest per-kg value can still dominate a build simply because you use tonnes of it. Concrete is the classic case. Its per-kg intensity is moderate, but the sheer mass in a typical structure makes it a major contributor.
A few materials in ICE use other units (for example, per m² or per functional unit) where that’s how the source data is reported. Always check the unit before you multiply. Mixing kg-based and area-based values is a common and costly slip.
How do you read ICE values — and what boundary do they cover?
Read ICE values as ordinal comparisons first, absolute numbers second. The dataset is strongest at telling you that primary aluminium is far more carbon-intensive per kilogram than structural timber, and that timber sits well below most metals. It’s weaker as a precise quote for a specific product from a specific supplier — for that, you need an EPD.
The boundary question matters most. Most ICE figures are cradle-to-gate: they count emissions from raw-material extraction through manufacturing, up to the point the material leaves the factory gate. That’s a clear, comparable boundary, but it’s narrower than whole-life carbon. It excludes transport to site, installation, in-use effects, maintenance, and end-of-life.
Whole-life carbon assessment widens the boundary across the building’s life, following an industry methodology such as the RICS Whole Life Carbon Assessment (RICS). The practical takeaway: a cradle-to-gate ICE value is a sound basis for comparing materials, but it isn’t a whole-building or whole-life number. Don’t present it as one. (We’re describing these boundaries qualitatively; we won’t put invented figures on them.)
A note on averages and variation
ICE values are typically averages, and real materials vary. Recycled content, fuel mix at the factory, and regional grid carbon all move the true figure. Two cement products with the same generic ICE value can differ markedly in practice. Treat the number as the centre of a range, not a point.
What are the ICE Database’s strengths and limits?
Its strengths are openness, breadth, and consistency. The ICE Database is free, covers a wide material span, and applies a comparable method across entries, which makes it ideal for early, like-for-like screening. For a team weighing material families before any formal assessment, that’s the right kind of reference, within the licence limits below.
The limits follow directly from how it’s built:
- Generic, not project-specific. Values are averages, not a measurement of your material from your supplier.
- Regional/temporal averaging. Figures reflect particular regions and production snapshots; your context may differ.
- Mostly cradle-to-gate. A narrower boundary than whole-life carbon — fine for material comparison, not for compliance reporting.
- Not certified. ICE is a reference dataset, not an EPD or a third-party-verified product declaration.
- Licence terms. Circular Ecology’s licence does not permit ICE data inside software tools, and from 30 September 2026 it rules out non-educational use. Read the current terms before you build ICE values into a tool or a commercial workflow.
None of this is a flaw; it’s a scope. ICE is built to inform decisions early and cheaply. The mistake is using it where a certified, product-specific figure is required. For compliance, certification, or official reporting, you move to verified EPDs and a formal LCA conducted by qualified professionals.
Does Elementa use ICE?
Not any more. Earlier versions of Elementa built their material values on the ICE Database. Those ICE-derived records have been removed: Circular Ecology’s licence does not permit ICE data inside software tools, and from 30 September 2026 it rules out non-educational use altogether. This article stays up because ICE is still worth understanding as a reference, not because Elementa runs on it.
Elementa now prices each layer from an ÖKOBAUDAT generic dataset (EN 15804+A2, modules A1–A3) pinned to that layer. It proposes the dataset that fits the project’s location first, generic before product-specific, and asks you when several fit equally. A pinned dataset keeps its version until you change it. A layer with no dataset pinned stays unpriced and is left out of totals rather than given a default figure. For when a generic dataset is enough and when you need a product EPD, see EPD or generic dataset under the EPBD.
Alongside the figure, Elementa shows an indicative impact class. Impact classes are computed per cubic metre (carbon × density): Low below 200, Medium 200–800, High above 800 kg CO₂e/m³.
| Impact class | Elementa cut-points (kg CO₂e/m³, A1–A3) |
|---|---|
| Low | below 200 |
| Medium | 200–800 |
| High | above 800 |
Working per cubic metre rather than per kilogram matters for the reason covered above: a dense material with a modest per-kg value can still carry a lot of carbon in each cubic metre you build. That is why concrete reads Medium despite a small per-kg figure. A material with no density recorded shows no class rather than a guess.
To be unambiguous: these figures and classes are indicative, for decision support — not for certification, compliance, or official reporting. They cover the product stage (A1–A3) only, and they don’t replace an EPD or a qualified LCA. They help you have a better conversation earlier, then hand off to formal assessment with a clearer sense of where the carbon hotspots probably sit.
For more on turning impact classes into specification choices, see Choosing material alternatives by impact class. For the wider context on why early material decisions dominate a project’s footprint, see the pillar guide to embodied carbon in construction.
FAQ
Is the ICE Database the same as an EPD?
No. An EPD (Environmental Product Declaration) is a third-party-verified document for a specific product, following a defined product category rule. The ICE Database is a generic reference dataset of average material values. Use ICE for early comparison; use EPDs and a formal LCA when you need certified, product-specific figures for reporting or compliance.
Are ICE values cradle-to-gate or whole-life?
Most ICE values are cradle-to-gate, covering extraction through the factory gate. They generally exclude transport to site, installation, in-use effects, and end-of-life. Whole-life carbon widens the boundary across the building’s life, following a methodology such as the RICS Whole Life Carbon Assessment. Don’t read a cradle-to-gate value as a whole-life number.
Can I use ICE values for compliance or certification?
No. The ICE Database is a reference dataset for indicative comparison, not a certified or compliance-grade source. For certification, compliance, or official reporting, use verified EPDs and a formal LCA carried out by qualified professionals. Check the licence terms too: Circular Ecology restricts use of ICE data in software tools and, from 30 September 2026, non-educational use.
Does Elementa use the ICE Database?
No. Elementa used ICE-derived values in earlier versions and has removed them, because the ICE licence does not permit use in software tools. Elementa now prices each layer from an ÖKOBAUDAT generic dataset (EN 15804+A2, modules A1–A3) pinned to that layer. A layer with no dataset pinned stays unpriced and is left out of totals. The results are indicative and for decision support only.
Why does concrete rank “moderate” yet still dominate my carbon?
Because ICE’s per-kilogram intensity hides quantity. A structure’s footprint depends on mass × intensity: concrete’s per-kg value is moderate, yet you use very large quantities, so its total contribution is often high. Elementa’s impact classes are computed per cubic metre (carbon × density) for this reason, which is why concrete reads Medium there despite a small per-kg figure. Either way, combine the class with how much of the material you’re actually using before drawing conclusions.
Use ICE values where they’re strongest
The ICE Database is a genuinely useful reference when you respect its scope: open, broad, consistent, and well suited to learning how material options compare — provided you read it as generic, mostly cradle-to-gate, and indicative, and stay within its licence. Elementa no longer uses it. It prices layers from pinned ÖKOBAUDAT generic datasets and shows Low / Medium / High impact classes per cubic metre, so teams can compare strategies before formal assessment, then move to certified EPDs and LCA when precision is required.
If you’d like to put structured, indicative material intelligence to work on your next project, start a project.