The office carbon footprint calculator shows how much CO₂e is associated with preparing the space and its subsequent operation. It separates the impact of materials, building services, equipment and construction from energy over the analysis period. It compares fit-out, modernisation and refurbishment and shows the effect of retaining existing elements.
Preparing an office is a functional, financial and environmental decision. A new fit-out from shell & core has a different footprint from a modernisation that retains existing elements, and from a refurbishment that restores the existing standard. Ecoffices Carbon Engine structures these differences: its primary result is the office preparation footprint within A1–A5, while the impact of energy use and replacements over the analysed operating period is shown separately. This makes it clear which part of the impact occurs at the start of the project and which accumulates later.
The scenarios below were calculated using the engine logic applied in version 3.0.8. They show three scopes of work — fit-out, modernisation and refurbishment — and the impact of resource retention, the functional programme, specification, building services, equipment, data quality and energy. They are comparative examples, not environmental declarations for specific projects.
| Scenario | Scope | Area | Users | Work model | Standard | Resource retention | Building services retained | Data quality | Energy | Cooling | Horizon | Preparation A1–A5 | Preparation / m² | Preparation / workstation | Operation | Total | Baseline / m² | Difference vs baseline | CO₂ value | Value / month | Data confidence | Main driver | Conclusion |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| S1High-retention refurbishment | Refurbishment | 320 m² | 32 people | Hybrid | Eco Refresh | 65% | 55% | Project-level | Supplier data · 0.120 kg/kWh | Existing VRF | 7 years | 14.8 t CO₂e | 46 kg CO₂e | 568 kg CO₂e | 29.0 t CO₂e | 43.8 t CO₂e | 74 kg CO₂e | −37.5% | 14 791 PLN | 176 PLN | 72 / 100 | retention of partitions, finishes and part of the building services | The lowest preparation footprint in the comparison. The benefit comes from actually reducing new materials, not from the name of the scope itself. |
| S2Modernisation with retention | Modernisation | 320 m² | 32 people | Hybrid | Eco Refit | 45% | 40% | Project-level | Supplier data · 0.120 kg/kWh | Optimised VRF | 7 years | 38.6 t CO₂e | 121 kg CO₂e | 1 485 kg CO₂e | 30.3 t CO₂e | 68.9 t CO₂e | 161 kg CO₂e | −25.3% | 23 276 PLN | 277 PLN | 72 / 100 | balance between retention, the programme and new building services | Modernisation has a higher initial footprint than refurbishment, but still benefits clearly from retaining existing elements. |
| S3New Eco Start fit-out | Fit-out | 320 m² | 32 people | Office-based | Eco Start | 0% | not applicable | Generic | Grid mix · 0.553 kg/kWh | VRF | 7 years | 55.9 t CO₂e | 175 kg CO₂e | 1 746 kg CO₂e | 179.2 t CO₂e | 235.0 t CO₂e | 175 kg CO₂e | 0.0% | 79 442 PLN | 946 PLN | 50 / 100 | new partitions, HVAC and grid electricity | Neutral reference point for a new fit-out. Over a seven-year horizon, energy has a larger impact than preparing the space. |
| S4New Eco Flow fit-out | Fit-out | 800 m² | 72 people | Hybrid | Eco Flow | 15% | not applicable | Project-level | Grid mix · 4% annual reduction | Chilled water | 7 years | 161.8 t CO₂e | 202 kg CO₂e | 2 697 kg CO₂e | 307.0 t CO₂e | 468.8 t CO₂e | 210 kg CO₂e | −3.8% | 158 462 PLN | 1 886 PLN | 72 / 100 | programme scale, building services and operating period | Retaining some materials reduces the preparation footprint, but energy still drives the result over the full period. |
| S5Eco Signature HQ | Fit-out | 1500 m² | 130 people | Office-based | Eco Signature | 5% | not applicable | Generic | Grid mix · 0.553 kg/kWh | VRF · high specification | 7 years | 528.2 t CO₂e | 352 kg CO₂e | 4 063 kg CO₂e | 1 170.7 t CO₂e | 1 698.9 t CO₂e | 310 kg CO₂e | +13.5% | 574 259 PLN | 6 836 PLN | 50 / 100 | specification, HVAC, glazing, IT/AV and server room | An extensive programme and high specification increase both material and technical layers. Product-level data is required for further verification. |
| S6ESG-optimised fit-out | Fit-out | 1000 m² | 95 people | Hybrid | Eco Flow | 45% | not applicable | Product-specific / EPD | Supplier data · 0.040 kg/kWh | District cooling | 7 years | 151.2 t CO₂e | 151 kg CO₂e | 1 989 kg CO₂e | 18.6 t CO₂e | 169.8 t CO₂e | 205 kg CO₂e | −26.3% | 57 389 PLN | 683 PLN | 92 / 100 | retention, local sourcing, disassembly and energy | A lower result requires work on both materials and operation. Low-carbon energy alone does not replace the need to reduce new resources. |
The difference between a high-retention refurbishment and an extensive HQ is almost 36 times. The scope, specification, programme and technology are decisive.
They should not be combined into a single figure without explanation. The first shows the impact of delivery; the second shows the consequences of energy use and replacements over time.
The percentage assessment does not compare different offices. It compares the scenario with the same area, scope, specification and programme using neutral settings.
Carbon Engine is a decision model for preparing and operating office space. Its primary result covers A1–A5: materials and products, transport, the preparation process and the elements required to make the office operational. The impact of subsequent operation is calculated separately based on area, declared energy consumption, building services, the energy factor and the analysis horizon.
This separation helps prevent misinterpretation. An office may have a low preparation footprint but a high energy impact in later years. It may also require more material at the start while using low-carbon energy. The engine shows both effects without blurring the distinction between them.
The model does not base the result on a single average factor. It separates the project into ten categories: construction works and partitions, finishes, HVAC, electrical and lighting, low-voltage systems and IT/AV, fire protection, controls and technical systems, furniture and built-ins, the server room, and transport, waste and site works. This makes it possible to identify project hotspots and see which decisions genuinely change the result.
The functional programme also matters. Meeting rooms, offices, phone booths, focus rooms, storage and shared functions affect the number of partitions, glazing and the scope of building services. Two offices with the same area and specification can therefore have different preparation footprints.
Fit-out assumes preparation of a new space and therefore usually has the highest share of new materials and building services. Modernisation uses a lower scope factor and can additionally account for retaining existing elements and equipment. Refurbishment has the lowest baseline scope of work, but its advantage depends on whether the project genuinely remains a refurbishment rather than a full rebuild described with a softer label.
Resource retention reduces the modelled impact of existing partitions and finish layers. For modernisation and refurbishment, the retained share of HVAC equipment can be defined separately. Reusing luminaires and floor boxes affects the electrical layer. The model therefore does not treat “reuse” as one general discount across the project, but assigns the effect to specific categories.
The result is also compared with the same project without retaining existing elements. This shows avoided emissions and the percentage reduction directly attributable to retention. In practice, the retained share should be confirmed by a technical audit rather than only declared at briefing stage.
The floor type, ceiling strategy and wall finish change the material intensity of the project. A retained floor, polished concrete, LVT, carpet or a mixed solution use different multipliers. The same applies to full, mixed or open ceilings, and to painted walls, PET panels and heavier wall coverings.
Glazing is calculated from the programme of meeting rooms and offices, the share of glazed partitions, doors, acoustic class and any fire-resistance requirements. Higher acoustic performance, EI30, door closers and access control increase the material or technical scope. The model also allows the sourcing locality of glass and other materials to be specified.
HVAC, electrical systems, lighting, fire alarm, sprinklers, BMS, low-voltage systems and the server room form the technical part of the preparation footprint. The same decisions later affect modelled energy consumption, but in a different way. More extensive ventilation or a higher HVAC specification increase modelled demand, while advanced controls and efficient lighting can reduce it.
The current operational model includes electricity and finish replacements resulting from the assumed service life. It does not separately calculate water use, heating from other energy carriers, employee transport emissions or refrigerant leakage. If these elements are material to a specific report, they require an extended analysis outside the scope of the Carbon module.
For the grid mix, the engine uses a factor of 0.553 kg CO₂/kWh and can model its percentage change in subsequent years. If the organisation has reliable contractual or supplier data, it can enter its own factor. Guarantees of origin, PPA agreements and the actual settlement factor should be distinguished — the module uses the value entered by the user but does not verify the source document.
Equipment is not automatically included in every scenario. The user specifies whether the analysis includes furniture, its scope and whether some equipment is refurbished. IT/AV can be enabled separately, together with the hardware policy and server-room parameters: type, area, number of racks, power and cooling standard.
The number of physical workstations comes from the permanent and flexible workstation programme. It is used to calculate the footprint per workstation and part of the equipment scope. The number of users remains a separate context, so the result per user and per workstation do not have to be the same.
The percentage assessment does not use a fixed Ecoffices benchmark. The engine builds a reference scenario for the same area, scope of works, specification and functional programme, but with neutral material and building-services settings. The analysed scenario is then compared with this baseline.
Published industry values, such as approximately 120–130 kg CO₂e/m² for selected fit-outs in a RICS context or 185 kg CO₂e/m² for the baseline scenario in the JLL Manchester case study, are shown only as context. They do not determine the project assessment because the scopes and boundaries of individual studies may differ.
Carbon Engine distinguishes between generic, design-level and product-specific data. A result based on general assumptions is suitable for early scenario comparison. Design-level data increases reliability because the programme and scope are better defined. The highest confidence level requires product-specific data or EPD declarations that allow factors for specific materials to be verified.
The confidence score does not certify the result. It only indicates the level of detail used to describe the analysed scenario. Even a high confidence score does not replace verification of quantities, manufacturers, EPDs and construction documentation.
The model converts the footprint using a default price of 78.59 EUR/t CO₂e and an exchange rate of 4.3010 PLN/EUR. These values can be changed. The monetary result is used to compare the scale of scenarios and support management communication. It is not a construction cost, rent, tax, fee or automatic offset price.
Carbon Engine is an early-stage decision tool. It is not a full LCA, an environmental declaration, an organisational emissions inventory or a regulatory audit document. It does not replace bills of quantities, EPDs, manufacturer data, actual material and energy quantities, or the definition of reporting boundaries required by a given standard.
The office preparation footprint depends on more than area or specification. It is shaped by the scope of works, functional programme, resource retention, materials, glazing, building services, equipment, logistics and data quality. During operation, energy use and potential finish replacements are added. Separating these elements is what makes it possible to compare a new fit-out, modernisation and refurbishment.
Ecoffices Carbon Engine does not automatically provide a single “green” answer. It shows the consequences of assumptions and compares the analysed scenario with a neutral version of the same project. This makes the environmental decision depend on the structure of impact rather than a marketing claim.
Ecoffices Carbon Engine analyses the carbon footprint of decisions related to office fit-out, modernisation or relocation.
This is not a full LCA audit, but a decision module that helps identify which project parameters most increase or reduce the CO₂e footprint and how changing one assumption affects the whole scenario.
The carbon footprint of an office fit-out is the sum of CO₂e emissions associated with preparing the space for use.
In practice, this means fit-out is not only a capital investment but also an environmental commitment over the office operating period.
Phases A, B and C show when emissions occur over the office life cycle.
This breakdown matters because some solutions increase the initial footprint but reduce emissions during operation. Without separating the phases, it is easy to misjudge which solution is genuinely more sustainable.
Not always. Staying usually reduces embodied carbon, but it may lock in a high operational footprint.
Staying in the current office can be beneficial if you can retain:
However, if the current office has poor energy efficiency, an unsuitable layout, excess space or outdated building services, its operational footprint may remain high throughout the lease.
Relocation can make environmental sense if the new building and layout significantly reduce the operational footprint.
It is then worth calculating the carbon payback point — the moment when the lower operational footprint starts to offset the higher initial footprint of the new fit-out.
Resource retention is an Ecoffices metric describing what share of the existing office elements is retained in the project instead of being removed.
Resource retention is one of the strongest ways to reduce embodied carbon because it limits the production, transport and installation of new materials. In practice, it requires a good existing-condition survey and a deliberate design approach.
The largest embodied footprint often comes from layers that are treated as standard fit-out elements.
Reducing an office carbon footprint therefore is not only about choosing an “eco material”; it also means eliminating unnecessary layers, retaining the right resources and designing durable solutions.
Electricity is one of the main drivers of an office’s operational carbon footprint.
If a company uses a lower-carbon tariff, guarantees of origin or a PPA, the operational footprint can fall significantly. The embodied footprint of materials and building services then becomes increasingly important.
HVAC affects both the embodied and operational footprint of an office.
The choice of cooling system, ventilation standard and level of controls therefore has major technical as well as ESG implications.
Environmental material data determines the reliability of a carbon-footprint calculation.
In practice, the absence of an EPD does not automatically mean a poor material, but it does mean lower model confidence and greater caution when interpreting the result.
The footprint of unused space is the share of emissions allocated to office area that has been built and maintained but is not actually used.
The issue is particularly visible in hybrid work. If a company designs an office for 100 people but only 45–60 actually use it at peak times, part of the materials, energy, cooling and lighting serves empty space.
A good ESG design should therefore assess not only the footprint per m², but also per workstation, employee and actually used space.
No. Carbon Engine is a decision and pre-design module, not a formal LCA audit.
Formal reporting requires exact material quantities, specific manufacturers, EPDs and detailed energy data. The module nevertheless helps make a better decision before the project enters an expensive detailed-design stage.
The largest reductions usually do not come from a single “green” material, but from a smart decision about project scope.
The best result comes from combining resource retention, efficient use of space, durable materials and a lower operational footprint.