Net Zero Carbon Tool

The 'Net Zero Carbon tool' can be used to calculate the net emissions of your building project by accounting for your building’s upfront, operating and end-of-life emissions and subtracting your benefits and offsets to receive the net emissions from your building project. 

Net Zero Carbon buildings focus on using less virgin materials, less fossil energy and fewer replacements throughout the lifetime of the project. They emphasize repurposable building materials, replacing fossil energy with renewable options and sequestering biogenic carbon. Net Zero Carbon can help take your project from less bad to good.

Life-Cycle & Results Scope

The Net Zero Carbon tool does not have a specific scope requirement, so the scope will be whatever parts of the building you include in your project and offsets will also be the ones you choose to include in your project. 

Data Scope

The Net Zero Carbon tool allows for EN15804+A1 (CML), EN15804+A2 (PEF) and TRACI data to be used.

Assessment Scope

The Net Zero Carbon tool does not have a specific minimum scope.

Include your construction materials

Fill in the building materials query of the design either manually or by import. Add all of your materials. This information will be used to calculate the raw material harvesting, transportation and manufacturing impacts in A1-A3.

Once the correct materials and quantities are provided, set the transportation distances from the material manufacturer to the project site and transport methods. The default transportation distances can be set up from the project’s LCA parameters page. If they are chosen, any material will use the average distance unless a more specific one is given in the query. This information will be used to calculate the impacts of material transportation in A4.

Check the material service life. This information will be used to calculate the material replacements for B4-B5. Material service life means how long each material will last in your building. If the service life is less than 60 years the material will have to be replaced. From an environmental impact point of view, this means additional emissions from the production of new material that is needed to replace the old one. Each of the materials in the One Click LCA database has a default service life. However, as the exposure conditions of the materials may vary, it may be good to check that the service life matches the condition of your building. It is especially important to check the external wall and roof material service lives as the weather conditions may vary greatly between areas.

If you have Expert features, adjust the localization of each material as needed (expert feature). This information will be used to compensate for any material data chosen from another area to match your project’s local material manufacturing conditions.

Enter your site operations (A5), energy (B6) and water (B7) demands (optional)

For construction site operations specify the climate region and construction site area (question 1 in the Construction site operations question form) OR input manually project-specific information in questions 2-5.

Include project-specific data for annual energy (kWh/y) and water (m3/y) consumption.

Fill in the emissions and removals query (optional)

This query looks at the use-phase emissions generated by refrigerants, concrete carbonisation and vegetation carbon withdrawals.

Fill in the Offsets & Net Zero Definition Query.

First, set your Net Zero definition. By default, all options have ‘Yes’ selected to be included in your Net Zero definition but you have the option to select ‘No’ from the dropdown if you do not wish to include a particular category. Categories which you exclude are not included in the calculation on the results page. 

• Next, add any carbon offsets you have purchased in the Verified Carbon Offsets section, choosing to attribute the offsets for up to completion (A1-A5) of the building or for the whole life (B1-C4).

Once your mandatory queries have been filled, you can view your results section, where results are split into Upfront Carbon (A1-A5), Operating Carbon (B1-B7) and End of Life (C-D). You can see any emissions that have been subtracted through biogenic carbon, materials reuse, exported energy and carbon offsets, and then view your final net carbon result in the bottom right corner. 

Set your calculation period and building area

Enter here the service life of the building required by the client or through regulations, for LCA this is also the reference study period/calculation period for the analysis. An often chosen calculation period is 60 years. This is the default calculation period in most BREEAM and LEED assessments.

Enter the building area in the respective question form. Specify as a minimum gross internal floor area (GIFA). This will be used to provide results per one m2, to make a possible comparison between different projects. You can find out more about the building area here.

Tips & Tricks

1. Invest in materials reduction in design - if your project can do without it, then go that route.
2. Remove or reduce systems where possible and incorporate carbon sinks where possible - selecting your location and placement for the building can make an impact on systems needed for the building. For example, building atriums with more natural sunlight can reduce energy costs for lighting.
   
3. Consider longevity and adaptability - build your structure with future adaptability in mind. 
4. Prioritize materials that can do more - Some materials are better at providing additional benefits such as producing energy, storing carbon and avoiding waste.
5. Leverage procurement to decarbonize supply - Source materials that have lower carbon impacts.