The purpose of the LEED v4.1 ID+C credit, MR Credit, Option 3 is to conduct a life cycle assessment of the project’s structure and interior fit-out. There are up to 3 credits available depending upon which path you would like to pursue.

Within Option 3, there are 3 paths you can choose from, which earn different amounts of credits:

Path 1: Conduct a life cycle assessment of the project’s interior (1 point)

Path 2: Meet the requirements of Path 1 and conduct a life cycle assessment of the project’s interior design compared against a baseline interiors project (2 points).

Path 3: Meet the requirements of Path 2 and incorporate building reuse and/or salvage materials into the project’s scope of work. Demonstrate reductions compared with the interiors project baseline of at least 20% for global warming potential and demonstrate at least 10% reduction in two additional impact categories listed below (3 points).

For Paths 2 and 3: The baseline and proposed interior projects must be of comparable size, function and operating energy performance as defined in EA Prerequisite Minimum Energy Performance. The service life of the baseline and proposed building interior must be the same to fully account for maintenance and replacement and must be a minimum of 20 years. Baseline assumptions must be based on standard design and material selection for the project location and building type. Data sets must be compliant with ISO 14044.

For Path 3, no more than one impact category assessed as part of the life-cycle assessment may increase compared with the baseline interiors project. Include a narrative of how the life cycle assessment was conducted and what changes were made to proposed interior design in order to achieve the related impact reductions.

Select at least three of the following impact categories for reduction, one of which must be GWP:

This guidance applies to the following One Click LCA tools:

This credit requires you to conduct a life-cycle assessment of the project’s entire scope of work, including structure and enclosure (if any), ceiling, wall, flooring, and interior partition assemblies including acoustic insulation, metal framing, finishes, coatings and furnishings.

The LEED tool reports stages A1-A3, A4, B3, B4-B5 and C1-C4.

In LEED v4.1 CML, TRACI and ReCiPe methodologies are accepted. Out of these methods, TRACI is commonly used in North America and CML is required by the EN standard and is, therefore, de facto the required methodology in Europe and also widely used internationally.

Below is a chart summarizing how TRACI, CML and ReCiPe differ in showing calculations for the different impact categories.

One Click LCA supports both TRACI 2.1 and CML (2002 – November 2012 or newer). LEED tools for US and Canada support TRACI 2.1 methodology and the versions for Europe and international users support CML (2002 – November 2012 or newer). In One Click LCA all of the datasets follow ISO14044 standards and thus, the data is automatically compliant with the required standards and required impact assessment methodology.

The materials and products could include but are not limited to: flooring, walls and wall systems, ceiling and ceiling systems glass and glass systems, furniture, lighting, doors, door frames/door hardware, interior finishes, nonstructural partitions, piping, plumbing, fixtures, ductwork, cabling, and fire suppression systems.

Create a building project and select the most relevant tool for your project:

"LCA for LEED, US (TRACI)"

"LCA for LEED, US (Canada)"

"LCA for LEED, Int'l (CML)"

Fill in the building materials query of the design either manually or by import. Add all of the materials required by the calculation scope (see above).

You are allowed to use either average data, manufacturer-specific EPDs (recommended) or similar products from another manufacturer. Use net quantities (amounts of material installed in the building); the on-site losses of materials would be included in module A5, but that is excluded from the calculation by credit specification.

This information will be used to calculate the raw material harvesting, transportation and manufacturing impacts in A1-A3.
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Once the 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.

This information will be used to calculate the material replacements for B4 impacts.

Material service life means how long each material will last in your building. If the service life is less than the service life of the building, the material will have to be replaced. From an environmental impacts 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 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.
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Adjust the localisation 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.

This information will be used as a divider for the results in a separate result row and it will help you to understand how the results compare to other projects. The gross floor area is required.

After you have done one calculation, you can create as many additional designs as you wish, either by copying the first one or by creating a new empty one. This can be used for creating a baseline or to create additional 'what if' scenarios. To copy a design click its name and choose 'Copy'. To create a new one press the '+ Add a design' button on the project main page.

Once the Baseline design is completed, create a copy of it and name it 'Proposed design'.

To make sure that the baseline and proposed models can be accurately compared, the following aspects must be kept the same in both the baseline and the proposed building:

Other portions of the baseline building may be modified from the basic ASHRAE 90.1 requirements to capture the LCA goals of the project team.

As a summary:

You can read more on baseline strategies in our guidance article: LEED Baseline Strategies.