Colorcoat® Column: Identifying the potential sources of CO2 emissions from a building
Levels of carbon dioxide in the atmosphere have been rising since the industrial revolution and are now rising at a rate faster than ever before.
This has led to raising temperatures over the 20th Century, the earth warmed by 0.6 degrees centigrade largely due to increased greenhouse gas emissions from human activities.
The UK climate impacts programme have carried out a number of climate change scenario assessments, which in all cases predict global surface temperature increases. Climate change and reduction in greenhouse gases is now an international agenda item with legally binding reduction targets.
The UK govenment target is to reduce CO2 emissions by 60% from the 1990 baseline level by 2050. In UK approximately 50% of all CO2 emissions are related to the operation of buildings
Which aspects of the building do I need to consider when looking to reduce CO2 emissions?
In order to minimise the CO2 emissions associated with a building, the designer should consider the whole lifecyle emission from cladding system manufacture, installation, building operation, building demolition and end of life.
- The CO2 which is generated during the building component manufacture and installation is usually referred to as the embodied CO2.
- The CO2 which is generated during the service life of the building for lighting, heating, cooling and activities within the building is usually referred to as the operational CO2 values.
What are the typical figures for embodied and operational CO2 emissions from a building?
The exact figures for the embodied CO2 and operational CO2 for a building will vary very greatly from building to building and will depend on a number of factors, including:-
- The lifespan of the building and the durability of the building components.
- The heating, cooling and lighting regime in the building.
In general for heated buildings, the operational CO2 will be greater than the embodied CO2 and typically the operation CO2 will account for 80 to 90% of the total emissions over the building life.
If embodied CO2 is such a small percentage of the overall building emissions, is it important and what can I do to reduce it?
Although the embodied CO2 only accounts for less than 20% of the total emissions, it is becoming increasingly important as legislation and other drivers increase the operational performance of the building. There are a number of actions which the building specifier can take to reduce this:
- Specify materials from suppliers who are actively looking at ways to reduce the embodied CO2 in their products.
- Make sure that the operational CO2 gains more than balance any additional embodied CO2 through building envelope enhancements such as increased insulation to inprove the building operational CO2 emissions.
- Specifying products which have greater durability will reduce the need for future maintenance and potential replacement and associated additional CO2 emissions.
Colorcoat HPS200® Ultra and Colorcoat Prisma® are available with Confidex Sustain® which allows the designer to offset all of the embodied CO2 within the building envelope against a range of climate friendly projects which reduce the use of fossil fuels.