We lease 14 branch offices and shops and cannot get any energy data: how does the Scope 3 guidance let us estimate Category 8?

Use the average-data method. Multiply each building type's floor space by an average of kilograms (kg) of carbon dioxide equivalent (CO2e) per square metre per year (Formula 8.4), or count assets by type times an average per asset (Formula 8.5). It is less accurate, so use it when bills or meter readings are not available.

When the guidance allows it

The Greenhouse Gas (GHG) Protocol says the average-data method "should be used when purchase records, electricity bills, or meter readings of fuel or energy use are not available or applicable". It adds that the method "is less accurate than the lessor-specific method and limits the ability of companies to track their performance of GHG reduction actions". Before using it, check whether the sites belong in Scope 2 instead under your consolidation approach.

The two formulas

• Formula 8.4, for buildings where floor space is known: sum across building types of (total floor space of the building type in square metres) times (average emission factor for the building type in kg CO2e per square metre per year).
• Formula 8.5, for assets other than buildings and for buildings where floor space is not known: sum across asset types of (number of assets) times (average emissions per asset type in kg CO2e per asset type per year).

Data and factors it asks for

• Floor space of each leased building, and the number of leased buildings by type, for example office, retail, warehouse, factory.
• Average factors by floor space (kg CO2e per square metre per year) or by building type (the guide's example is kg CO2e per small office block per year).
• The guide names the U.S. Energy Information Administration's Commercial Buildings Energy Consumption Survey as a source of average energy use by building type. That is United States data. We found no Indian figure in the guidance, so name the source of any factor you use for your sites and label the result an estimate.

Replace it as soon as you can

Start with the sites that use the most power, such as air-conditioned branches open long hours, and get bills or sub-meter readings for those. Keep the average-data method for the small remainder.

Fourteen leased sites (example figures)

• Office-type branches: 8 sites, 2,400 square metres in total, example factor 100 kg CO2e per square metre per year: 2,400 x 100 = 240,000 kg
• Retail-type branches: 6 sites, 1,500 square metres in total, example factor 150: 1,500 x 150 = 225,000 kg
• Formula 8.4 total: 240,000 + 225,000 = 465,000 kg CO2e, which is 465 tonnes
• If floor space of the 6 retail sites were unknown, Formula 8.5 with an example 37,500 kg per site: 6 x 37,500 = 225,000 kg

The factors are numbers for the arithmetic only. They are not published factors. Do not use them in a report.

What Senseible does here

Senseible reads fuel invoices and electricity bills into monthly records. Upload what you do have, such as electricity bills for the sites where you pay them, and use them in place of the estimate for those sites.

• Floor share with occupancy rate
• Franchise estimate by floor space
• Leased factory: which scope
• Free calculators

Sources: GHG Protocol Technical Guidance for Calculating Scope 3 Emissions, Category 8 (average-data method, Formulas 8.4 and 8.5)

Last reviewed 2026-11-06. Formulas and wording are from Chapter 8. Check any factor you choose for year, area and building type.