Embodied carbon – does your insulation specification add up?
The long-term focus of the building industry will remain on building energy efficiency. But Vanessa Rae, Marketing and Sustainability Directorat Knauf Insulation, warns that there can be no path to net-zero unless embodied carbon is also considered.
The amount of embodied carbon in a building quickly adds up, especially when some construction products have exceptionally high levels. So, it makes sense to look for the “low-hanging fruit” – products where compromise is unnecessary. This is products such as insulation, which deliver the performance you need for a modern, sustainable building but are also low in embodied carbon.
Therefore, embodied carbon must form part of the design strategy and specification process now.
How it’s made counts
Every construction product has a different carbon footprint, including these that have the same function, such as mineral wool and rigid board insulation. So, the key to this “quick win” is to understand the factors that contribute to embodied carbon.
Mineral wool insulation is made from materials that come from naturally abundant sources or are recycled, reducing the use of virgin materials and waste to landfill.
Another consideration is how the product obtains its thermal resistance. Some insulation products contain pentane, which has a global warming potential (based on the levels of embodied carbon) that is five or ten times more harmful than CO₂. In comparison, mineral wool insulation simply uses trapped air, which has a global warming potential of zero.
Embodied carbon can also vary between products made from the same material. For example, Knauf Insulation’s unique bio-based binder, ECOSE® Technology, is 70% less energy-intensive to manufacture than traditional binders. It is also made from natural, rapidly renewable raw materials.
Then there is transport, and some consideration should also be given to the packaging. Knauf Insulation’s glass mineral wool insulation can be compressed during the packaging process, so there is more product per pack and packs per pallet. This means more insulation can be transported in one go, reducing the number of trucks on the roads and transport-related carbon emissions.
Accurate information is essential
Of course, architects and specifiers can only calculate the embodied carbon of their projects if they have accurate product data.
There are a variety of sources available, including the manufacturer’s environmental product declarations (EPDs) to EN 15804 or lifecycle assessments (LCAs). Other accreditations include BES 6001 for responsible sourcing within the construction supply chain and the DECLARE label, which brings transparency to sustainability claims. It lists a product’s ingredients and life expectancy, as well as verified responsible sourcing.
Architects’ legacies are the buildings they design. By specifying products such as mineral wool insulation that are low in embodied carbon, they will ensure that their buildings perform in the real world and create a legacy that will deliver for many years to come.