How to Calculate Your Office Carbon Footprint When You Rent or Share an Office
Calculating your office carbon footprint can become more complicated when your business rents its workspace, shares a building with other organisations or works from a serviced office.
You might not receive the electricity bill directly, your landlord may manage the heating, or several businesses could share the same energy meter. In some serviced offices, energy costs are simply included within the rent or service charge, leaving you with very little information about how much energy your organisation actually uses.
If this sounds familiar, the important thing is not to assume that a lack of perfect data means you cannot start measuring your office emissions. You need to understand how the premises fit within your greenhouse gas inventory, find the best information reasonably available and clearly record where estimates or assumptions have been necessary.
At Scope, we think this distinction matters. A carbon footprint becomes much more useful when you understand the data behind it, rather than focusing only on producing a final CO2e figure.
This guide explains how to approach a rented office carbon footprint, what energy information to ask your landlord or workspace provider for and what you can do when accurate consumption data isn't readily available.
Does a Rented Office Count Towards Your Business Carbon Footprint?
A rented office can contribute to your business carbon footprint because emissions associated with leased premises may need to be included within your greenhouse gas inventory, depending on your organisational boundary and the activities you are accounting for.
Under the GHG Protocol, emissions from leased facilities can be classified as Scope 1, Scope 2 or Scope 3 depending on the source of the emissions, the approach your organisation uses to establish its organisational boundary and the leasing arrangement.
This is an important distinction because renting an office does not automatically make all the emissions associated with that office Scope 3.
Where a leased asset falls within your organisational boundary, relevant direct emissions may fall within Scope 1, while indirect emissions associated with purchased electricity may fall within Scope 2. Where the leased asset sits outside that organisational boundary, associated emissions may instead be accounted for within Scope 3.
For a business measuring its footprint for the first time, the terminology can make a fairly practical question sound unnecessarily complicated. Before worrying about which scope to enter against a spreadsheet or carbon tracking platform, establish what you rent, what energy sources are involved and how the premises fit within the boundary you are using for your inventory.
If you're new to these categories, our guide to Scope 1, Scope 2 and Scope 3 emissions explains how the three scopes fit together.
What Are Upstream Leased Assets?
Upstream leased assets are assets that a business leases from another organisation and operates during its reporting period, where the associated emissions aren't already included within its Scope 1 or Scope 2 inventory.
Within the GHG Protocol's Scope 3 framework, these emissions are covered by Category 8: Upstream Leased Assets.
For a business renting office space, the building or part of the building it leases may therefore be relevant when establishing its greenhouse gas inventory. However, that does not mean every rented office should automatically be recorded under Scope 3 Category 8.
The correct treatment depends on how the leased premises fit within your organisational boundary and whether the relevant emissions are already included within Scope 1 or Scope 2.
Our advice is to resist the temptation to assign a category simply because you've found a definition that sounds similar to your situation. Establishing the reporting boundary first gives you a much stronger basis for deciding how your leased building emissions should be treated.
What Data Do You Need to Calculate an Office Carbon Footprint?
To calculate an office carbon footprint, businesses should collect energy consumption data for relevant sources such as electricity, gas and purchased heating or cooling, alongside information showing which premises and reporting period the data covers.
For a business that owns and manages its premises directly, some of this information may already be available through utility bills, meter readings or energy-management systems.
When you rent or share an office, however, the information may sit with your landlord, building manager or serviced-office provider instead.
The data you need will depend on the building and the energy sources involved, but useful information can include:
Information | What to look for |
Electricity | Electricity consumption in kWh for your office or relevant building |
Gas | Gas consumption in kWh or another clearly stated unit |
Heating or cooling | Consumption information for purchased heat, steam or cooling where relevant |
Reporting period | The dates covered by the consumption figures |
Meter coverage | Whether the meter covers your office, floor or whole building |
Shared energy | How your organisation's share of consumption has been calculated |
Supporting records | Meter readings, utility information or landlord records where available |
For UK activities, the Government publishes company reporting conversion factors that allow organisations to calculate greenhouse gas emissions from activity data such as fuel use and purchased electricity. These factors are updated annually.
One of the most useful habits you can develop at this stage is keeping the context alongside the number. Knowing that your business used 5,000 kWh is useful, but knowing where that figure came from, which dates it covers and whether it represents actual or allocated consumption makes the data much more valuable for future reporting.
If you're unfamiliar with the calculation stage, our guide to emission factors explains how activity data can be converted into CO2e.
What Energy Data Should You Ask Your Landlord For?
Businesses renting or sharing office space should ask their landlord or workspace provider for energy consumption data covering their premises and reporting period, together with enough information to understand exactly what the figures include.
Even if energy costs are included within your rent or service charge, it is worth finding out whether more detailed consumption information exists behind the amount you pay.
Your landlord, building manager or serviced-office provider may hold meter readings or building-level energy records that aren't shown on your own invoices.
Useful questions can include:
Can you provide electricity consumption in kWh for our reporting period?
Is our office separately metered for electricity or gas?
If it isn't separately metered, can you provide consumption for the whole building or our floor?
What areas and tenants are included within that figure?
Is heating or cooling provided centrally?
Are there separate consumption figures for those services?
If energy has already been allocated to our organisation, how was our share calculated?
Are meter readings, bills or other records available to support the figures?
The aim isn't simply to obtain a number from your landlord. You need to understand what that number represents.
For example, 20,000 kWh of electricity could represent your individual office, one floor of a building or the consumption of every tenant in the property. Without that context, it becomes much harder to know whether the figure can be used directly or needs to be allocated.
This is an area where a little extra information can significantly improve your carbon data. Rather than asking your landlord for “our carbon emissions”, asking for the underlying energy consumption and what it covers can give you a clearer record to work from.
How Do You Calculate a Shared Office Carbon Footprint?
When several organisations share the same energy meter, calculating a shared office carbon footprint may require part of the building's total consumption to be allocated to your organisation using the most appropriate information available.
The starting point should still be the best actual consumption data you can obtain. If your office has a sub-meter, for example, that can provide more specific information than dividing the consumption of an entire building between its tenants.
Where tenant-specific consumption isn't available, an allocation may be needed. The method should reflect the information available and should be documented so that somebody reviewing the calculation later can understand how your organisation's figure was reached.
Consider a simple example where a building uses 10,000 kWh of electricity during the reporting period and your organisation occupies 100 m² of 1,000 m² of comparable tenant space.
An illustrative floor-space allocation would be:
100 m² ÷ 1,000 m² = 10%
Applying that proportion to the building's electricity consumption would give:
10,000 kWh × 10% = 1,000 kWh
The resulting 1,000 kWh is an estimate of the electricity allocated to your organisation, rather than a directly measured consumption figure or a carbon emissions figure. You would still need to use the appropriate carbon accounting method and emission factor to convert the relevant activity data into CO2e.
At Scope, we think being clear about that distinction is more useful than creating a figure that looks more precise than the underlying data really allows. Recording that the electricity was allocated using floor area gives future users of the data important context and creates an obvious area to improve if better information becomes available.
How Can You Track a Rented or Shared Office in Scope?
Scope allows businesses to enter their office energy use and account for electricity bills or meters that are shared with other occupants, helping turn the office data you have collected into part of your wider carbon footprint calculation.
In Scope's Business Energy & Water section, you can enter the electricity your business or site used during the reporting period. Where you have your own electricity bill or meter, you can enter the electricity consumption in kWh along with information about your electricity supplier.
For businesses in shared offices, serviced offices or other multi-occupancy buildings, there is an additional step. Scope asks whether the electricity meter or bill is shared with other occupants.
If it is, you can enter the percentage of the bill that relates to your business. Scope then calculates your share of the electricity consumption rather than treating the entire building's electricity use as your own.
For example, if the shared electricity figure is 50,000 kWh and your business is responsible for 60%, Scope calculates your share as 30,000 kWh.
If you are unsure of your percentage, the platform suggests dividing your floor area by the building's total floor area as one way of estimating your share. As we explained earlier, floor area will not always reflect differences in how individual occupants actually use energy, so more specific tenant-level information should be used where it is available.
Scope's Energy & Refrigerant section also asks about other energy-related activities, including gas and how the site is heated. This helps you record the information that actually applies to your premises rather than assuming every office has the same energy sources.
The important part is still the quality of the information you enter. Scope can help you organise the calculation, but you should understand where your original energy figure came from, what it covers and whether your share is based on measured consumption or an allocation.
Can You Estimate Office Energy Use If Your Landlord Doesn't Have the Data?
Office energy consumption may need to be estimated when actual consumption data isn't available, but the calculation should clearly identify the data source, estimation method and assumptions rather than presenting the result as an exact measurement.
This situation can arise when a landlord cannot separate your energy use from other tenants, historic meter information is unavailable or a serviced workspace does not provide individual energy consumption to occupiers.
If you're calculating your business footprint for the first time, reaching this point can make it feel as though you don't have enough information to continue. In practice, carbon data is not always complete from the outset, particularly when important information sits with landlords, suppliers or other organisations.
Before estimating, check whether there is another source of more specific information. Building-level consumption, sub-meter readings, landlord records or information covering part of the reporting period may all be more useful than immediately moving to a broad proxy.
Where more specific activity data cannot be obtained, an estimate may provide a practical starting point, provided its limitations are understood and documented.
If your calculation relies on an estimate or proxy, keep a record of:
what information was unavailable;
what alternative data was used;
where that data came from;
how the estimate or allocation was calculated;
which assumptions were made; and
which reporting period the calculation covers.
For us, this is one of the most important principles in practical carbon tracking: an estimate that is clearly identified and documented is very different from an estimate presented as though it were an exact measurement.
Keeping that record gives you a clearer audit trail and makes it easier to replace the estimate with better data during a future reporting period.
Is Floor Space the Best Way to Divide Shared Office Energy?
Floor space can provide a practical way to allocate shared-building energy consumption when more specific information isn't available, but it isn't automatically the most representative method for every rented or shared office.
Two businesses could occupy exactly the same floor area while using very different amounts of electricity. One might have a small number of employees working on laptops, while another could have substantially more people or equipment operating throughout the day.
There may also be better information available. Individual sub-metering, tenant-level consumption records or another reasonable allocation supplied by the building manager could provide a more representative picture than floor area alone.
The aim should be to use the best information reasonably available, rather than choosing whichever allocation produces the most favourable result. If floor space is the best basis you have, record that clearly and consider whether more specific information could be collected next time.
How Do You Convert Office Energy Use Into Carbon Emissions?
Office energy consumption can be converted into carbon dioxide equivalent (CO2e) by applying an appropriate emission factor to the relevant activity data, using the correct factor and reporting method for the energy source involved.
At its simplest, an emissions calculation can be expressed as:
Activity data × emission factor = greenhouse gas emissions
For example, electricity consumption might be recorded in kilowatt-hours and then combined with the relevant emissions information to calculate CO2e.
For UK activities, the Government publishes annual company reporting conversion factors that organisations can use for activities such as electricity consumption and fuel use.
If you are new to carbon reporting, it is worth remembering that the emission factor is only one part of the calculation. A technically correct factor cannot compensate for activity data that has been misunderstood, which is another reason to keep information about the source and coverage of your office energy figures.
How Can You Improve Your Office Carbon Footprint Over Time?
Businesses can improve the quality of their rented office carbon footprint over time by replacing estimates and broad allocations with more specific consumption data where it becomes available, while keeping a clear record of changes in methodology.
Your first calculation may rely on whole-building electricity consumption divided using a reasonable allocation because that is the best information your landlord can provide.
During the next reporting period, you might be able to request tenant-specific consumption, arrange access to sub-meter readings or agree a more representative allocation with the building manager.
That doesn't make the earlier calculation useless. What matters is knowing how each figure was produced so that changes in your reported emissions can be interpreted properly.
This is the approach we encourage at Scope: start with the best carbon data you can reasonably obtain, understand its limitations and create a clear path towards improving it. Carbon tracking becomes more valuable when it develops into an ongoing process rather than an exercise you have to reconstruct from scratch every year.
If you're gathering carbon information from different parts of your organisation, our guide to carbon data sources businesses already have can help you identify other records that could support your calculations.
Calculate Your Business Carbon Footprint
Calculating your office emissions can help build part of your business carbon footprint, but your wider inventory may also need to consider sources such as transport, business travel, waste and purchased goods and services.
The exact activities included will depend on your reporting boundary and what you are trying to measure, which is why it is useful to keep the underlying data organised rather than focusing only on one final carbon figure.
Scope's free Business Carbon Calculator can help you start turning the business data you already have into an initial carbon footprint.
You don't need every part of your carbon data to be perfect before you begin understanding your footprint. What matters is knowing what information you have used, where assumptions or estimates were necessary and where there are opportunities to collect better data next time.
As your reporting develops, Scope can help you bring that information together and build a clearer, more consistent picture of your emissions over time.
Office Carbon Footprint FAQs
Does a Rented Office Carbon Footprint Count Towards Scope 3?
A rented office does not automatically count as Scope 3 because emissions associated with leased premises may fall within Scope 1, Scope 2 or Scope 3 depending on the emissions source, the company's organisational boundary and the leasing arrangement.
Businesses should therefore establish their reporting boundary and understand the activities associated with their leased premises before assigning those emissions to a particular scope.
What Is Scope 3 Category 8?
Scope 3 Category 8 covers upstream leased assets operated by the reporting company where the associated emissions aren't already included within its Scope 1 or Scope 2 inventory.
A rented office can potentially fall within this category, but businesses should establish how their leased premises fit within their organisational boundary rather than assuming every rented property is automatically Category 8.
How Do I Calculate My Office Carbon Footprint If Energy Is Included in the Rent?
Businesses with energy included in their rent should first ask their landlord or workspace provider for actual consumption data before deciding whether an estimate or allocation is necessary.
If your office isn't separately metered, building-level consumption may still be available and could potentially be allocated using an appropriate method. Any allocation or estimate should be recorded clearly so that it isn't confused with directly measured consumption.
Can I Use Floor Space to Estimate Energy Use in a Shared Office?
Floor space can be used as an allocation basis when more specific tenant-level energy data isn't available, provided the approach is appropriate to the circumstances and is clearly documented as an estimate.
Where sub-metering or more representative tenant-level information exists, that information may provide a better basis for calculating your organisation's share of energy consumption.
What Energy Data Should I Ask My Landlord For?
Businesses should ask their landlord for electricity, gas and any other relevant energy consumption covering the reporting period, together with information showing whether the data relates to their individual premises or a wider shared building.
Where the landlord has already allocated part of the building's consumption to your organisation, you should also ask how that allocation was calculated and whether supporting records such as meter readings are available.
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