How does eToolLCD calculate the burdens and benefits associated with recycling?

eToolLCD follows the EN15978 standard for calculating recycling burdens and benefits.  What this means in simple terms is:

If the building designer is hoping to understand the net benefits associated with recycled content in buildings products used for construction and refurbishment, they should report Modules A-C inclusive.  In other words, reporting Modules A-C rewards the use of recycled content in new products.

If the building designer is hoping to understand the net benefits associated with recycling rates in the waste streams from refurbishment and demolition at the end of a products life they should report Modules A-D inclusive.  In other words, reporting Modules A-D rewards design for deconstruction (high recycling rates in the waste stream).

The methodology that drive this approach is that only the net outflow of a product is considered in Module D.  So if a material used in the buildings has a very high recycled content (when new) but a lower recycling recovery rate (in the waste stream) there will be negative net flow of material for secondary use from the system and a burden will be applied in Module D.  If on the other hand a product has a low recycled content and a high recovery rate there will be a large positive net outflow of material for secondary use and a benefit will be applied in Module D.

Closed Loop Recycling

The figure below demonstrates how impact calculations are made for the different life cycle phases. In this example, the material is made up of 40% recycled content and 60% primary production content. The impacts associated with primary production are 10units. The impacts associated with secondary production are 2 units. Based on these parameters, the calculation for Module A1-A3 is:

A1-A3 = Primary Impact x Primary Content (%) + Secondary Impact x Secondary Content (%)

A1-A3 = 10 x 0.6 + 2 x 0.4

A1-A3 = 6.8

At the end of the building life, 10% of the material is lost to landfill due to collection losses, corrosion, materials embedded within waste etc. 90% of the material hence flows through to secondary production. In EN15978, a benefit of only 50% of the total material input (not 90%) is claimed in Module D because of the original material contained 40% recycled content. So the net benefit calculated in module D is:

D = (Recycling Rate – Secondary Content) x (Secondary Impact – Primary Impact)

D = (0.9 – 0.4) x (2 – 10)

D = 4

Although this method means that the values of A1-3 and D will change depending on both recycled content and end of life recycling rate, the net impact (A1-3 + D) is entirely dependent on end of life recycling rate. If a study excludes reporting of Module D, the recycling allocation approach matches that of a recycled content allocation (100%,0%) and if Module D is included, it matches that of an end of life recycling rate allocation (0%,100%). In other words, the design for recovery and reuse methodology is supported in determining net impacts due to recycled content and recycling rates. A similar example is given in the Product Category Rules for Aluminium Products (European Aluminium Association 2013).

Closed Loop Recycling

Open Loop Recycling

Materials that are recovered for downstream use in other materials re-entering the economy need special treatment to differentiate where impacts and benefits will be allocated. Examples include:

  • Brick waste that is crushed and used in road base
  • Concrete waste that is crushed and used in road base
  • Plastics that are down cycled into less pure products
  • Glass that is crushed and used as aggregate

These materials do offset the use of primary materials and hence can have net benefits on the environment where recovery makes sense. As the materials they are replacing often have very low primary impacts anyway (eg road base), the benefits can be marginal and may depend largely on transportation distances.

Economic allocation is used to differentiate where benefits and loads should be accounted for. If a material is a genuine waste at the end of the building life cycle (negative value or zero value) then at this point no benefits can be claimed for this building, and the next building (recovered materials used in place of primary materials) will claim the benefit in modules A1-3. If the material has value at the end of the building life, the net benefits of recovery and primary material offsetting can be claimed in module D.

Can materials manufacturers load their products into eToolLCD?

Yes, but there are some data requirements. As a minimum, a supplier should have conducted an environmental product declaration on their product. We also look for EPDs that are registered with a member of the ECO EPD Platform. Members are listed here:

Reasons for choosing one of these program operators are:

  • Ensures compliance with ISO 14025 (it’s not an EPD if it isn’t registered with an EPD program operator) which also ensures it’s thorough, objective and likely to be reliable
  • The ECO EPD platform includes all the main EPD program operators who are currently aligning their product category rules for construction products so that all EPDs between programs will be entirely comparable. Essentially they’re creating the currency for environmental product information for the construction sector.
  • Europe lead the way with EPD activity and this system will likely become the dominant international system for construction products.
  • The ECO EPD system will also comply with EN15804 and can therefore be used in whole building LCA studies compliant with EN15978
  • ALCAS and ALCANZ (the Australian and New Zealand representative bodies for LCA) are initiating a local EPD program which aligns with the International EPD System who are also members of the ECO EPD platform

These factors essentially mean that it’s the best way of ensuring an EPD is relevant and recognised Internationally .

Note for Australian Manufacturers:

In addition, if material manufacturers are undertaking EPDs in Australia for products likely be used for Green Star projects, they should extend their reporting of environmental indicators to include the GBCA’s current list of environmental indicators required for the whole of life, whole of building LCA credits as follows:

  • Climate change (Kg CO2, equivalent IPCC AR4)
  • Stratospheric ozone depletion potential (Kg CFC 11 equivalent, WMO 1999)
  • Acidification potential of land and water (Kg SO2 equivalent, CML)
  • Eutrophication potential (kg PO4 equivalent, CML)
  • Tropospheric ozone formation potential (Photochemical Ozone Creation Potential Ethylene equivalents, CML)
  • Mineral and fossil fuel depletion (abiotic depletion) (Kg Sb equivalent, CML)

The following indicators also enable an extra Green Star point can be obtained:

  • Human Toxicity (Kg 1,4 DB equivalent, DALY)
  • Land use Land Transformation (m2 UNEP/SETAC Land Use Indicator Value Calculation in Life Cycle Assessment)
  • Resource depletion – water (m3 water use related to local scarcity of water, Water Stress Indicator)
  • Ionising Radiation (kg U-235 equivalent to air Human Health Effect model)
  • Particulate Matter (kg PM2.5 equivalent RiskPoll)

The indicators that are currently required for EN15978 are listed in green, those that are not required are red, and those that have different characterisation methods are orange. So if a manufacturer is producing an EPD and want it to be useful for Green Star purposes, it’s a good idea to include all these indicators regardless of whether they’re strictly required for the EPD.

A list of Australian practitioners is available on the ALCAS web site (link below), many of whom could provide EPD services.

We’re happy to answer questions from suppliers about EPDs.

What LCA standards does eToolLCD comply with?

There are no ISO standards that we can measure our software against that are specific to life cycle assessment.  There are however a number of standards that eToolLCD can be used to report against.  The user still has a responsibility to ensure their report writing (publishing the numbers from eToolLCD) and inputs into eToolLCD are robust and compliant with the standard.  The standards that eTool methodology and calculations are currently compliant with include:

  • ISO 14040  2006:  Environmental management – Life cycle assessment – Principles and framework
  • ISO 14044  2006:  Environmental management – Life cycle assessment – Requirements and guidelines
  • EN 15978  2011: Sustainability of construction works. Assessment of environmental performance of buildings. Calculation method

What Functional Units does eToolLCD use?

In order to normalise assessments between building types the environmental and cost impacts are expressed in terms of an applicable functional unit.  Typically eTool uses the following functional units for different project types:

  • Commercial Office: Impacts are either measured:
      • Per Occupant Hour
      • Per m2 per year
  • Residential buildings: Impacts measured per occupant per year
  • Community, healthcare, retail: Impacts are either measured:
      • Per Occupant Hour
      • Per m2 per year
  • Industrial buildings: Impacts measured per m2 per year

All the functional units rely on a prediction of design life, which has a very large effect on their comparable sustainability. Although difficult to predict, eTool uses a methodology aimed at producing fair and repeatable comparisons between building designs. Individual building life spans will deviate significantly from the design lives calculated using this methodology, however the aim is to predict the mean expected life of all buildings with similar characteristics and circumstances.

Although studies that quantify the actual life span of buildings are lacking, the reasons for demolition of buildings are quite well documented. Studies conducted in Australia (Kapambwe, Ximenes, F, Vinden, & Keenan, 2009) and the US (Athena Institute, 2004) indicate that less than 10% of buildings are demolished due to reaching the end of their strutural service life. It is other factors that usually dictate service life, namely:

  • Redevelopment for economic reasons (surrounding land has increased in value to the extent that it is more profitable to increase the density or use of the buliding)
  • Redevelopment for aesthetic reasons (the building is no longer in fasion)
  • Fire or other disaster

For this reason the following characteristics are also considered when estimating design life:

  • Building density
  • Density of the surrounding suburb
  • Design quality

Best practice building design attempts to match the durability with the redevelopment potential of the building.

The eTool estimated design lives often differ compared to industry perceptions of building life span. Architects in Australia for example expect detached residential buildings to last over 60 years (Kapambwe, Ximenes, F, Vinden, & Keenan, 2009).

What are the System Boundaries of eToolLCD?

The current eToolLCD scope is shown in the below diagram.  Although broad, the omission of demolition and recycling impacts must be noted as this has potential to be significant in an unbounded LCA.  eTool is working now to include demolition, disposal and recycling and as credible data becomes available this will be built into subsequent versions of eToolLCD..  The eTool database does however store an estimated percentage of recyclable materials used in the construction of the building which can be reported on separately. Please contact us for more information.

Do we use the BP LCI database for materials?

Not at this stage. The BP LCI Data is unfortunately “Gate to Gate” data which does not account for the impact of the input of materials to the manufacturing process. The BP LCI team acknowledge this shortcoming and hope to expand their assessment boundary to include cradle to gate impacts.

In the meantime eToolLCD uses international LCI data. We hope to incorporate the BP LCI in one form or another as soon as the data provides cradle to gate, weighted and normalised LCA data.