February 2024

Knauf Insulation Tech Talk
EMBODIED CARBON: WHY SHOULD
YOU CARE?
While insulation improves energy efficiency, it’s not the only factor that affects a
building’s carbon footprint. In his latest column Bradley Hirst, Technical Services
Manager from Knauf Insulation, answers common questions about another
sustainability measure – embodied carbon.
What is embodied carbon?
The UK Green Building Council defines
embodied carbon as the total greenhouse
gas emissions (carbon) associated with
materials and construction processes throughout
the whole lifecycle of a building asset or
infrastructure. It includes the emissions from the
extraction of raw materials, manufacturing,
processing, transportation, maintenance and
disposal of every product and element used in that
asset, as well as the construction process itself.
This differs from operational carbon which is the
greenhouse gas emissions from the energy used
to run the building (heating, lighting, maintenance
etc.) as well as energy used by occupants.
Are there regulations about embodied
carbon?
Not yet, but it’s becoming increasingly important
because it must be addressed to hit net zero. RIBA
has already set targets for levels of embodied
carbon as have many construction clients.
Do all insulation products contain the
same amount of embodied carbon?
No. The amount of embodied carbon a product
contains is affected by factors such as how it’s
made, packaged and transported.
Take mineral wool for example. Knauf Insulation’s
glass mineral wool is made from up to 80%
recycled content, mostly glass bottles and jars.
While our rock mineral wool uses volcanic rock, a
material from naturally abundant sources, and
recycled slag, a waste product from blast
furnaces. The amounts and type of energy
Above: Using recycled glass cullet to manufacture glass
mineral wool insulation uses less energy than is needed for
virgin raw materials
required to produce them are different too.
Most of our products are manufactured with
ECOSE Technology, our unique bio-based binder
that contains no added formaldehyde or phenol. It
is made from natural raw materials that are
rapidly renewable and is 70 per cent less energyintensive
to manufacture than traditional binders.
We also compress our glass mineral wool
insulation so there’s more product per pack or
pallet, so less packaging is used. This means
there’s more product per truck so fewer vehicles on
the roads and less associated carbon emissions.
In contrast, rigid boards are made using oil-based
materials and cannot be compressed because it
would damage the insulation.
How can you check levels of embodied
carbon?
Ask for the manufacturer’s Environmental
Product Declaration (EPD) for the product. These
should comply with European standard EN
15804, or International Organization for
Standardization (ISO) standards 14025, 14040,
Bradley Hirst, Technical Services Manager, Knauf Insulation.
14044, or 21930. They should also be verified,
audited, and approved by an independent,
accredited third party.
Where the EPD complies with EN 15804, there
are two methodologies that may have been used
for the calculations – the older EN 15804+A1
standard, and the new EN 15804+A2. Any EPDs
issued after July 2022 must comply with the new
standard. This new standard helps with
specification because it increases the scope and
granularity of data provided, but it does make
comparing EPDs produced using different
methodologies difficult.
Glass mineral wool is a good choice because it
has the lowest level of embodied carbon of any
mainstream insulation material.
Knauf Insulation produces EPDs to the +A2
standard for all its products, which can be
downloaded from www.knaufinsulation.co.uk.
Contact Knauf Insulation
www.knaufinsulation.co.uk
Knauf Insulation UK & Ireland
38 TC FEBRUARY 2024