Coulter BIM Information Management

In the previous post we looked at Ireland’s new Green Public Procurement (GPP) circular. This week, let’s expand on what that means for carbon in BIM — particularly how embodied and operational carbon are managed, and how this all connects to the RIBA Sustainable Outcomes Guide.

Ireland’s Circular 17/2025 – raising the bar

The Irish Government’s Circular 17/2025 makes carbon reporting a mainstream requirement for public projects. From 2026, large public buildings (over 1,000 m²) will need to report whole life carbon (WLC) in line with EN 15978.

This isn’t just a policy statement — it’s a procurement obligation. Tender documents, EIRs, and BEPs will need to show exactly how carbon data is captured, delivered, and verified. For BIM managers, that makes carbon a core digital deliverable, not a side report.

Embodied carbon – counting materials

Embodied carbon covers the CO₂ associated with materials and construction processes (EN 15978 modules A1–A5, plus replacements and end-of-life).

In practice, this means taking material quantities from BIM model take-offs or cost plans and multiplying them by carbon factors from Environmental Product Declarations (EPDs).

Tools in use: EC3, TallyCAT, One Click LCA, eToolLCD.

Stage responsibilities: Architects and structural engineers lead early estimates; suppliers and contractors refine the numbers later with real product EPDs.

Information Manager’s role: Make sure schedules, classifications (e.g. Uniclass), and identifiers are in place so that embodied carbon tools can map data cleanly.

Operational carbon – the MEP responsibility

Operational carbon (EN 15978 modules B6 and B7) is about the energy and water used during a building’s life. Heating, cooling, lighting, pumps, and fans all sit under this heading.

This falls squarely into the realm of MEP engineers and energy experts. They use tools like IES VE, DesignBuilder, or PHPP (the Passive House Planning Package) to model energy demand in kWh/m²/year, which can then be converted into CO₂e.

While architects influence form and fabric, it’s the energy modelling team who take responsibility for delivering the operational carbon figures. On larger commercial jobs, PHPP alone often isn’t enough — so results from dynamic simulations are simplified back into PHPP for Passive House certification, or delivered directly for EN 15978 compliance.

Whole life carbon – bringing it together

Whole Life Carbon (WLC) is simply embodied + operational + end-of-life. What’s changing with Ireland’s GPP is that this combined picture is now mandatory for public projects.

For information managers, this means:

Updating EIRs and BEPs to specify carbon deliverables.

Making sure the Responsibility Matrix assigns embodied carbon to design teams and suppliers, and operational carbon to MEP engineers.

Clarifying how the data is delivered — reports, spreadsheets, or model exports — all valid under ISO 19650.

Does it all need to be in the model?

A common concern is whether every carbon figure has to sit inside the BIM model as a parameter. The answer is no.

Models should provide quantities and identifiers (geometry, Uniclass, GUIDs).

Carbon calculations are best handled in external tools (EC3, One Click LCA, energy software).

Results can be delivered as structured reports, Excel schedules, or COBie extensions.

ISO 19650 makes clear that any information container is valid — as long as it’s structured, traceable, and reviewable.

The RIBA Sustainable Outcomes Guide – already ahead of the curve

The RIBA Sustainable Outcomes Guide set the agenda back in 2019 by defining measurable outcomes:

1. Net zero operational carbon
2. Net zero embodied carbon
3. Sustainable water cycle
…plus five more on biodiversity, wellbeing, and social value.

Those first two outcomes map perfectly onto EN 15978’s framework. Ireland’s Circular 17/2025 has effectively taken the RIBA targets and made them policy requirements.

For BIM information managers, this creates a neat triangle:

RIBA Sustainable Outcomes Guide – sets the vision and targets.

EN 15978 – provides the calculation method.

ISO 19650 – ensures the data is structured and managed in the CDE.

Closing thoughts

Carbon is no longer just “someone else’s report.” With Circular 17/2025, it becomes a core part of digital deliverables in Ireland, and the UK/EU are heading the same way.

The good news? We already have the tools and standards:

Embodied carbon through BIM take-offs and LCA tools.

Operational carbon through energy modelling.

Whole life reporting aligned with EN 15978.

Frameworks like the RIBA Sustainable Outcomes Guide and ISO 19650 to hold it all together.

For BIM managers, the task now is to integrate carbon into the same workflows as drawings, models, and COBie. That means updating EIRs, BEPs, and Responsibility Matrices, and ensuring the outputs flow through the CDE in a structured, auditable way.