How it works

Four steps

1. 1

   Create a project

   A project is one building. Enter its gross floor area (GFA) if you know it, so results can also be shown per m².

2. 2

   Upload a variant

   Upload the bill of quantities (Excel list of materials and amounts) and, optionally, the IFC model. Each design option (e.g. concrete vs timber) is its own variant.

3. 3

   The app finds an EPD for each material

   The AI searches the Quarry database for the Environmental Product Declaration that best fits each material. Unsure matches are marked "needs review" and are not counted until you check them.

4. 4

   Read, compare, improve, prove

   See the total carbon and the biggest sources, compare variants side by side, let the optimizer suggest lower-carbon materials, and generate a receipt anyone can verify.

The AI only searches for and matches data. All arithmetic is plain, tested code, so the same input always gives the same number.

How to read the results

The headline number

Product stage A1–A3 in tonnes CO₂e: the carbon released to make the materials. It is the most reliable figure because every EPD declares it.

Per m²

The same number divided by floor area. Use it to compare buildings of different sizes. Shown only when the project has a GFA.

Coverage

For example "92 % (40/44)" means 40 of 44 material lines are in the total. The other 4 are listed with the reason; fix them on the Materials tab.

Hotspots

The lines with the most carbon. Swapping one hotspot material usually saves more than many small changes.

Hover any kg value

Numbers with a dotted underline show how they were calculated: quantity × conversion × EPD value, and which EPD and page it came from.

Match statuses

auto-matched

Matched automatically with high confidence. Counted in the total.

confirmed

A person confirmed this EPD. Counted in the total.

needs review

The AI is not sure enough, or the units could not be converted. Not counted until you confirm it or pick another EPD.

no match

No suitable EPD found. Not counted. Search for one or upload an EPD PDF.

rejected

A person rejected this EPD. Not counted.

Glossary

Embodied carbon

The greenhouse gases released to make, transport, build with and dispose of building materials, as opposed to the energy used to run the building.

CO₂e

CO₂ equivalent. All greenhouse gases converted into the amount of CO₂ that would warm the climate equally, so they can be added up. 1 t = 1,000 kg.

GWP

Global Warming Potential: the climate impact of a material, measured in kg CO₂e. This is the number the app calculates.

EPD

Environmental Product Declaration: an independently checked document from a manufacturer that states the environmental impact of its product, e.g. "1 m³ of this concrete = 250 kg CO₂e".

Quarry

An online database of EPDs. The app searches it to find a matching EPD for each material.

Bill of quantities

An Excel list of every material in the building and how much of it there is (m³, m² or kg). This is where the quantities come from.

IFC model

The 3D building model exported from design software (Revit, ArchiCAD…). Optional: it links each material line to a wall, slab or window in the model.

GFA

Gross floor area in m². Dividing the carbon by it gives kg CO₂e per m², which lets you compare buildings of different sizes.

Variant

One design option of the same building, e.g. a concrete, a brick and a timber version. Each variant has its own bill of quantities.

Line item

One row of the bill of quantities: one material layer of one building element.

Life-cycle stages

EN 15978 splits a building's life into stages: A1–A3 making the materials, A4–A5 building, B1–B7 use, C1–C4 end of life, D benefits after end of life.

A1–A3

Product stage: raw material extraction, transport to the factory and manufacturing. Usually the biggest share, and the one every EPD declares.

A4–A5

Construction stage: transport to the site and the building work itself.

B1–B7

Use stage: maintenance, repair and replacement of materials while the building is used.

C1–C4

End of life: demolition, transport away, waste processing and disposal.

Module D

Benefits and loads beyond the building's life, e.g. credit for recycled steel. Reported separately and never added to the total.

A–C declared

Sum of all stages from A1 to C4, but only those the EPDs actually declare. A stage an EPD does not declare is left out, not counted as zero.

Coverage

How many lines of the bill of quantities are included in the total. Lines without a reliable EPD match are left out and listed with the reason.

Hotspot

A line that causes a large share of the carbon. Changing hotspots is the fastest way to reduce the total.

Confidence

How sure the AI is that the EPD fits the material (0–100 %). Below 70 % the match needs your review before it counts.

Declared unit

The amount of product the EPD values refer to, e.g. 1 m³ or 1 kg. The app converts your quantity into this unit before multiplying.

Conversion

How your quantity (e.g. m³) was turned into the EPD's unit (e.g. kg), for example using the material density.

Carbon receipt

A file that lists how every kg CO₂e was calculated. Anyone can upload it on the Verify page to check that nothing was changed.