How to calculate the carbon footprint for heating?

Kuva: Pixabay

In this post I’ll reveal how you can calculate the carbon footprint for heating in 3 easy steps. Before going into details, let me remind you why heating emissions are a big deal: In cold Finland, keeping buildings warm accounts for 25% of the energy consumed. That’s a lot. It’s even more than is used by motor transport, which accounts for “only” 16% of the energy used. The whole energy sector is responsible for 75% of Finland’s total greenhouse gas emissions. That’s why it’s important to focus on heating, be it in your own office or rented premises.

For an art organization, its baseline climate impact comes from heating exhibition spaces and the office. IHME’s only permanent location is its office, and we use rented venues for events. For carbon calculations, this means two different ways of filling in the data.

Case study: office heating

How to find data about the carbon footprint from heating an office? With an office located in an apartment building the most knowledgeable people are the real-estate managers. The first step is to contact them. Their contact details can be usually found in the entrance hall, and our office building was no exception. It was quick and easy to get an energy certificate from the real-estate manager. I did ask for a carbon footprint calculation as well, but, even in 2020, the reply to that question is silence.

What struck me about the energy certificate was that, on scale from A to G (A being the most energy-efficient), our building was in Class F – almost as F in Failed! After recovering from the shock, I found a clear figure for district heating per square metre. With a little help from Google I managed to find the specific emissions for the Helsinki-based energy company Helen. I multiplied that by the number of square metres in the office and I was ready. Almost. I noticed Carbon-smart calculator added an extra 20% for emissions caused by the energy supply chain.

  • Energy used in our building: 194 kWh/m2 per year 
  • Our office area: 70 m2 
  • District-heating emissions from the local energy company: 198 g CO2/kWh  
  • + 20% for the supply chain

Case study: individual event

Calculating the carbon footprint from heating rented premises is another story. This is where carbon calculators come in handy. The only thing left to do is to ask the right question from the right person. In the Carbon-smart calculator that we use, we only need to fill in the length of the event in hours and the size of the venue in square metres. To make it even easier, some rentable venues list their square-metre area on their websites. I hope they will soon add carbon footprint information, too.

4 steps to calculate the carbon footprint from heating an office  

  1. Find out the size of the office
  2. Find out the (annual) district-heating energy consumption:
    1. Contact the real estate management office (contact information usually in the entrance hall)
    2. Ask for the building’s energy consumption report for the previous year (should be available in February – March)
    3. Look for district heating per square metre (kWh/m2) in the certificate/report
  3. Find out the specific carbon emissions (g CO2/kWh) at the site Local power (available in English) 
  4. Enter the data into your carbon calculator (or multiply the numbers and add an extra 20% for the energy supply chain)

2 steps to calculate the carbon footprint for an event  

  1. Find out the size of the space in square metres: Check the website or ask whoever rents out the venue.
  2. Enter the number of hours your event lasts in the carbon calculator. 

What about the results?

In conclusion, it is possible and fairly easy to calculate the carbon footprint for heating both for the office and an individual event. The carbon footprint for our office was 3.2 tonnes CO2 and the carbon footprint for an event was 4 kg CO2. Is that a lot or not? That’s a good question, and the answer depends on how you frame it. I’ll discuss that in another post.


This article is part of a series published in 2020 about the carbon footprint of an art production, written by IHME eco-coordinator Saara Korpela.

Read all Ecoblog posts published in 2020:


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