Embodied carbon

Overview

Embodied carbon adds up the kgCO2e of a BimCraft model. Each element's quantity (volume, area, length, mass or count) is multiplied by a factor from a table, by life-cycle module, and the totals are shown by material, class and storey, and per square metre of floor. The factor table is open and editable. The rows that ship with BimCraft are starter values to replace with your own source. Today this is part of BimCraft's core, not a separate add-on.

Who it’s for

• Sustainability and whole-life carbon consultants: an early estimate of a building's embodied carbon by material and storey.
• Quantity surveyors and estimators: carbon next to the quantities they already take off.
• Designers comparing materials: change a factor or a material and see the total move.

What you can do

• Open the Carbon pane in BimCraft to read the totals by material, class, storey and per square metre of floor.
• Edit the factor rows in the pane, or import and export the table as CSV or JSON.
• Choose a different factor row for one element; the choice is kept in the model.
• Choose the modules to count: A1 to A3 (product stage) always, and A4 (transport) and A5 (site waste) when asked and the row has a figure.
• Type the floor area that the per-square-metre figure uses.
• See the elements with no matching factor or no quantity in the Problems panel, rather than counted as zero.

Methods and standards

Quantity times factor for each element, by life-cycle module (A1 to A3, A4, A5 as the add-on labels them), summed by material, class and storey. A factor's basis sets the quantity: mass from volume times density, or volume, area, length or count. Quantities come from the element's own quantity set (net or gross volume, area or length), or from the volume of its closed mesh when there is none; a layered material splits the volume by layer thickness.

Data and sources

The shipped factor rows are generic starter values for common materials. They are not from a licensed database or an environmental product declaration, and every row is marked unchecked. Replace them with your source (an EPD, a national database, or your firm's figures) by editing the pane or importing CSV or JSON. Rows you add override the starter row with the same id, and the table is saved in the model.

Verification

bin/test-bimcraft.mjs --carbon (tools/bimcraft-test/eg-carbon-test.mjs) checks the factor table format, the carbon engine against figures worked by hand, and the totals on a small IFC model with layered walls and a floor. Not yet checked against a reference case with published factors.

Limits

An early-design estimate from the factors you load. It is not an assessment, a certified figure or a compliance result. The shipped factors are unchecked starter values, so a total is only as good as the factors and quantities behind it. Module A4 and A5 are counted only where a row has a figure, and the pane reports the gaps.

Files and formats

Reads the open IFC model (materials, quantity sets, storeys and classes). Saves the factor table and element choices in the model's project and element property sets (CadCraft_CarbonFactors and CadCraft_Carbon). Exports the factor rows as CSV or JSON (format cadcraft-carbon-factors) and the totals as CSV.

Get started

1. Open a BimCraft model whose elements have materials and quantities.
2. Open the Carbon pane and read the totals by material and storey.
3. Replace the starter factors with your own source, edit the rows, and read the totals again.

Languages

No languages are listed for this add-on yet. Its maker may add some.

Works in

Comes with

Nothing else.

Needed by: Architecture, Construction engineering and management, Energy and building performance modeling, Facilities and maintenance engineering, Renewable energy (solar, wind, storage).

Versions

Licence and maker

CadCraft (CadCraft, first-party). Licence: Apache-2.0. Dependencies carry their own licences, listed on their pages.