# My floor has no sub-meter: how does the GHG Protocol say to estimate my share of the building's energy?

Canonical: https://senseible.earth/answers/ghg-leased-floor-share-with-occupancy-rate

Divide your floor area by the building's total area multiplied by its occupancy rate, then multiply by the building's total energy use. The Greenhouse Gas (GHG) Protocol's example: 200 square metres in a 2,000 square metre building at 75% occupancy gets 200 / (2,000 x 0.75), 13.3% of the energy.

## The formula

Energy used by your space in kilowatt hours (kWh) = your area / (building total area x occupancy rate) x building total energy use. Dividing by occupied area, not total area, shares the energy among the space that is in use. Do it separately for electricity, fuel and refrigerant top-ups, then apply each factor.

## The Greenhouse Gas Protocol's own example

- A tenant leases 200 square metres of a 2,000 square metre building, 75% occupied.
- Building totals: gas 1,500 kWh, electricity 3,000 kWh, 5 kg of refrigerant leaked.
- The tenant's share is 200 / 1,500 = 13.3%: 200 kWh of gas, 400 kWh of electricity, 0.67 kg of refrigerant.
- At the example factors in the guide, that is 1,325 kg of carbon dioxide equivalent (CO2e).

## When to use it

It belongs to Scope 3 Category 8 (upstream leased assets) when the lease is not already in your Scope 1 or 2. The guide offers three methods, in order of the data you have: the building's own meter data, the landlord's emissions allocated by area, and an average per square metre for the building type. The occupancy rate comes from the landlord, so keep the email or statement that gives it.

## A 400 square metre floor, 80% occupied (estimate)

- Share: 400 / (4,000 x 0.80) = 12.5%, not 10%
- Building electricity 3,60,000 kWh a year: 12.5% = 45,000 kWh
- 45,000 x 0.675 = 30.4 tonnes carbon dioxide (CO2) a year; without the occupancy rate, 36,000 kWh and 24.3 tonnes

The 4,000 square metre building, 80% occupancy and 3,60,000 kWh are example numbers. Grid factor: Central Electricity Authority financial year 2025-26, an estimate.

## What Senseible does here

Senseible reads electricity bills and fuel invoices into monthly records with dates. If your landlord passes on a bill or a statement for the building, the figures sit on record, but the share by floor area and occupancy rate is a step you set.

- [Mall common area electricity: who gets what](https://senseible.earth/answers/mall-common-area-electricity-allocation)
- [Rented unit for part of the year: Category 8](https://senseible.earth/answers/leased-asset-part-year-category-8)
- [Coworking space: Scope 2 or Category 8](https://senseible.earth/answers/coworking-space-emissions-scope-2-or-category-8)
- [Rented factory: which scope](https://senseible.earth/answers/leased-factory-emissions-which-scope)

Sources: [GHG Protocol, Technical Guidance for Calculating Scope 3 Emissions, Category 8](https://ghgprotocol.org/sites/default/files/2022-12/Chapter8.pdf), [GHG Protocol, Corporate Value Chain (Scope 3) Standard](https://ghgprotocol.org/corporate-value-chain-scope-3-standard), [CEA, CO2 Baseline Database for the Indian Power Sector](https://cea.nic.in/cdm-co2-baseline-view?mappingId=234&lang=en)

Last reviewed 2026-11-04. The guidance is dated 2013. Re-check if the GHG Protocol's Scope 3 revision changes how leased assets are allocated.