Modeling Carbon Neutral Products in eTool

When it comes to modeling carbon neutral products in eTool, you need to bear in mind that most carbon neutral certified products use carbon offsets to achieve that certification. In order to offset the carbon of a product, a LCA needs to be conducted first in order to find out what the carbon impact of the product is which is then offset outside of the LCA. For products, the LCA comes in the form on an EPD which reports on the environmental impact of that particular product. LCAs give you the information on how much carbon you need to offset in order for the product to achieve carbon neutrality.

With that understanding, it isn’t sound methodology to then go backwards and change the LCA of that product to zero after you’ve offset that carbon. Hence why EN 15978 standards do not include carbon offsets in the LCA boundary scope and why at Cerclos, we do not certify LCAs that has modeled carbon offsets. However, it is possible for a product to be carbon neutral without using carbon offsets. Therefore effort must be given to ascertain this when conducting an LCA to EN15978 standards.

LCAs are used to calculate how much carbon a product has to know how much needs to be offset outside of the LCA.

However with the increasing pressure on achieving carbon neutral targets, EPD operators have now started producing ‘carbon neutral’ EPDs that incorporate carbon offsets into their EPDs to improve the appeal of their products. Some rating schemes such as Green Star have also started accepting the use of these EPDs for their points calculation.

At Cerclos, we strive to remain rating scheme agnostic while endeavouring to support our users with achieving their LCA goals in line with EN & ISO standards. Below we have complied our recommendations on how to model carbon neutral products in eTool while remaining in compliance to EN/ISO standards.

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How to Model A Design with Carbon Neutral Products in eTool

Should you wish to demonstrate the benefit of the carbon neutral product that have used carbon offsets in eTool, this will need to be modeled outside of the headline LCA to ensure alignment with EN 15978.

Below is an example of how to model your carbon offset neutral product scenario which should be modeled after the certified Final/Proposed Design to meet EN 15978 standards while being able to demonstrate to your clients the benefits of using carbon neutral products.

Please note that you are now allowed to include carbon neutral products for Upfront Carbon points in Green Star Buildings. Please follow our reporting recommendation below to generate the report for GS. The relevant quality checks will be left in question to highlight the deviation from EN15978.

Below are two different ways to model your carbon offset neutral product, please choose the most appropriate method according to your requirements.

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Method 1 – ‘Zero impact materials’ using Bulk Swap Tool

***To maintain traceability please modify the template name to identify the zero impact material***

To model your carbon neutral product using ‘Zero impact materials’, please follow the steps below:

1. Click on Bulk Swap Tool which is located on the top right side of your design, next to ‘+Add Template’.

2. Select Material category

3. Filter by Material Name

4. Select ‘contains’ and write the name of the material you would like to replace with the Carbon Neutral product

5. Click on Find to filter

6. Select all items to be replaced

7. Select Material as the parameter to make the necessary changes

8. Select ‘Zero Impact Product or Material’ as the material to be changed for

9. Add your selection

10. Hit on Apply changes

For more guidance on how to use the Bulk Swap Tool. Please refer to this support post.

Alternatively, you can ask the material supplier for an EPD and use that to account for the carbon neutral products. To create the EPD in eTool, please refer to this support post.

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Method 2 – Use ‘Negative’ Material

To model your carbon offset neutral product using ‘Negative’ Material, please follow the steps below:

  1. Navigate to the category where your carbon offset neutral material is in. In this example, the carbon offset neutral concrete is in the Substructure. Note the current GWP impacts under the ‘Products’ category (highlighted).
  2. Next, click ‘+Add Substructure‘ to add a new element which in this case, will be the same Concrete | Unreinforced | Portland Cement Blend | 40 MPa material.
  3. In the material pop-up window, make sure that you enter the negative amount of the quantity you want to offset (pay attention that the units are correct as well) and that the inputs for ‘Lost or Damaged in Transport’ is changed to be the same as the default material. The ‘Disposal or Recovery Method’ & ‘New Product Transport to Site’ inputs (as highlighted below) need to be set to zero to ensure that only A1-A3 material impacts are offset.
  4. Click ‘Save’ to add the new material to the category.
  5. Back in the category summary view, you’ll now see that only the GWP for Products and Transport (A1-A4) has been affected while all other impacts have remained the same.
  6. You can also confirm this by running a custom table in the Analysis Tab. Note that the inputs under A4 are only for the impact of any products lost or damaged in transport.

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Reporting from eTool

Once your Final/Proposed/As-Built Design has been certified and your carbon neutral products scenario design has been reviewed (it won’t be certified), you may proceed with generating a report from eTool. You can do this by running the LCA report from the Carbon Neutral Products Scenario Design.

Reporting for Green Star Buildings

Once your Final/Proposed/As-Built Design has been certified and your Carbon Neutral Products Scenario design has been reviewed (it won’t be certified), you may proceed with generating the LCA report from the certified Proposed/Final Design. Below are the steps to generate your LCA report.

  1. In your ‘Carbon Neutral Product’ scenario, under ‘Set Scenario Purpose’ change it to ‘Improved Design’. Save to implement the changes.
  2. Jump into your Proposed/Final Design and then the ‘Reports’ tab to generate the LCA report.
  3. Turn on the ‘Compare Against Benchmark’ & ‘Include Comparison’ buttons.
  4. Under the Benchmark option, select your Reference Design while under the Comparison option, select your Carbon Neutral Product Scenario Design.
  5. Click ‘Generate’ to generate your LCA report.


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Related Articles:

Modelling Carbon Neutral Construction in eTool

GreenPower & Renewable Energy Purchase Agreements in LCA

Model Construction Equipment Energy Use Offsets (Module A5)

How to Model Carbon Offsets for Remaining Impacts 

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