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.
- Elementa turns ICE values into indicative impact classes (Low / Medium / High) for early decisions — 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 exactly the right tool.
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.
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.
How does Elementa use ICE values?
Elementa uses ICE Database values as its data foundation, then translates them into indicative impact classes to support early decisions, not to certify them. Rather than ask a practitioner to interpret a raw per-kg figure during a fast comparison, the platform bands materials into three intuitive classes by their embodied-carbon intensity.
| Impact class | Elementa band, over ICE values (kg CO₂e/kg) | Typically reads as |
|---|---|---|
| Low | lowest band | bio-based / inert (e.g. structural timber) |
| Medium | middle band | mixed materials |
| High | highest band | fossil-based / intensive (e.g. primary aluminium) |
The classes are relative bands, not published cut-points: they order materials against each other for early comparison. Elementa derives them from ICE Database values; ICE itself publishes no banding.
These bands are deliberately coarse. They’re meant for the moment before commitment, when you’re comparing a timber frame against a steel one, or deciding whether to retain an existing element rather than replace it. Elementa carries 544 material records derived from the ICE Database — a curated subset rather than the full inventory, chosen for breadth across the categories that come up in early-stage comparison.
To be unambiguous: these classes are indicative, ICE-Database-based estimates for decision support — not for certification, compliance, or official reporting. 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 these bands 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. Elementa’s impact classes, which are built on ICE values, are likewise indicative and for decision support only.
Why does concrete rank “moderate” yet still dominate my carbon?
Because impact class is per kilogram, but a structure’s footprint depends on mass × intensity. Concrete’s per-kg intensity is moderate, yet you typically use very large quantities, so its total contribution is often high. Always combine a material’s class with how much of it you’re actually using before drawing conclusions.
Use ICE values where they’re strongest
The ICE Database is a genuinely useful tool when you respect its scope: open, broad, consistent, and ideal for comparing material options early — provided you read it as generic, mostly cradle-to-gate, and indicative. Elementa builds on that foundation, banding ICE values into Low / Medium / High impact classes 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, join the waitlist.