INSULATION
Defining embodied carbon and energy
Embodied carbon( EC): Embodied carbon comes from the consumption of energy consumed to extract, refine, process, transport and fabricate a material or product( including buildings). It is often measured from cradle to( factory) gate, cradle to site( of use), or cradle to grave( end of life). The embodied carbon footprint is therefore the amount of carbon( CO2 or CO2e emission) required to produce a material. 1
Embodied energy( EE): EE is the total primary energy consumed from direct and indirect processes associated with a product or service, within the cradleto-gate boundary. This includes all activities from material extraction( quarrying / mining), manufacturing, transportation and right through to fabrication processes until the product is ready to leave the final factory gate.
Applying existing data to calculate the GWP of popular insulation materials is complex. Among other things, there is a scarcity of accurate information, and some materials suppliers greenwash their product information.
For example, where to allocate system boundaries as defined by a Life Cycle Analysis in performing EC / EE calculations.
For recycled materials, the popular approach is to claim a factory gate value of zero for recycled feedstock, using the Recycled Content Approach( RCA). This approach assigns a material value of zero for energy and carbon at the factory gate. Bear in mind that recycled materials may have been shipped to factories over long distances from their sources. For example, recycled plastic, glass waste bottles or even newsprint“ dumped” in South Africa from the Far East.
Then claims are often made that the carbon sequestered( embodied) in the previous life of the original raw material( e. g. trees) may be carried over into the next life stage, yielding a net negative zero carbon at factory gate. Architects, developers and engineers should take note that this is also greenwashing.
Embodied energies carried by installed insulation materials to achieve specified R-values Achieving SANS10400-XA: 2021 required R-Value of 3.5 for Thermal Regions 1- 7
Material / Product Typical
EE |
EC |
Density |
Recommend |
|
|
|
Installation depth |
Mass Per Installated m2
Figures MJ / kg kgCO2 / kg kg / m3 mm( SANS10400-XA) In kg
Cellulose Insulation fibre( recycled substrate)
Glass Wool Blanket( typical)
PET Blanket( partly recycled substrate)
EE per Installated m2
3,3 0,63 27,5 135 3,71 12,25
Ref: The ICE- Hammond and Jones, pub. BSRIA Guide 2011
28 1,35 18 135 2,43 68,04
89,2 – 10 170 1,70 151,64
EPS( Expanded) Board 88,6 2,55 15 120 1,80 159,48
XPS( Extruded) Board 47,3 – 32 100 3,20 151,36
Hemp fibre( based on virgin hemp shiv)
* Ref: Hill et al, 2018
10 – 39 150 5,85 58,50
* Ref: G. Grazieschi et al. 2021
*** Wood wool- virgin 10,8 – – – – –
NOTE Hemp shive values are estimations, based on measured results plus wood wool parameters.
Table 1: The embodied energy values for each popular insulation type, calculated to the required deemed to satisfy installed thickness, per 1m2 of the surface being insulated. Numbers as per desktop survey done in 2023.
Having applied the RCA once to a recycled raw material means no“ doubledipping”. Therefore, a realistic account must be made of the embodied carbon / energy content of a product made from recycled materials considering emissions of original embodied carbon if dumped or incinerated at its end-of-life.
So how does this apply to insulation made from natural fibre, such as cellulose?
Typical EC / EE values and R-values
South Africa’ s building regulations are rather specific for building insulation. Under the deemed-to-satisfy energy building efficiency approach, R-values are specified for each of the country’ s energy zones.
Low Embodied Carbon Cellulose Fibre Insulation For Compliant, Energy-Efficient Builds.
info @ eco-insulation. co. za
SUSTAINABLE INSULATION STARTS HERE.