NC-v4.1 MRc1: Building Life-Cycle Impact Reduction 2-5 points

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Intent

Requirements

Demonstrate reduced environmental effects during initial project decision-making by reusing existing building resources or demonstrating a reduction in materials use through life-cycle assessment.

Achieve one or more of the following options below for a maximum of 5 points.

Option 1. Building and Material Reuse (1-5 points)

Maintain the existing building structure, envelope, and interior nonstructural elements. Reused or salvaged materials from off site that are incorporated into the building can also contribute to the credit calculations. However, reuse materials contributing toward this credit may not contribute toward MR credit- Sourcing of Raw Materials.

Historic, abandoned or blighted buildings: Portions of buildings deemed structurally unsound or hazardous can be excluded from the credit calculations.

Path 1 and 2 reward projects that reuse structural and/or nonstructural elements based on the project area. Path 1 and 2 can be combined for points.

Table 1. Path 1 Points for reuse of existing building structural elements.

Option 2. Whole-Building Life-Cycle Assessment (1-4 points)

For new construction (buildings or portions of buildings), conduct a cradle-to-grave life-cycle assessment of the project’s structure and enclosure and select one or more of the following paths below to earn up to 4 points:

Path 1: Conduct a life cycle assessment of the project’s structure and enclosure (1 point).

Path 2: Conduct a life cycle assessment of the project’s structure and enclosure that demonstrates a minimum of 5% reduction, compared with a baseline building in at least three of the six impact categories listed below, one of which must be global warming potential (2 points).

Path 3: Conduct a life cycle assessment of the project’s structure and enclosure that demonstrates a minimum of 10% reduction, compared with a baseline building, in at least three of the six impact categories listed below, one of which must be global warming potential (3 points).

Path 4: Meet requirements of Path 3 and incorporate reuse and/or salvage materials into the project’s structure and enclosure for the proposed design. Demonstrate reductions compared with a baseline building of at least 20% reduction for global warming potential and demonstrate at least 10% reduction in two additional impact categories listed below (4 points).

For Paths 2, 3 and 4 listed above, no impact category assessed as part of the life-cycle assessment may increase by more than 5% compared with the baseline building. Include a narrative of how the life cycle assessment was conducted and if applicable for paths 2, 3 and 4 what changes were made to proposed buildings in order to achieve the related impact reductions.

The baseline and proposed buildings must be of comparable size, function, orientation, and operating energy performance as defined in EA Prerequisite Minimum Energy Performance. The service life of the baseline and proposed buildings must be the same and at least 60 years to fully account for maintenance and replacement. Baseline assumptions must be based on standard design and material selection for the project location and building type. Use the same life-cycle assessment software tools and data sets to evaluate both the baseline building and the proposed building, and report all listed impact categories. Data sets must be compliant with ISO 14044.

• global warming potential (greenhouse gases), in kg CO₂e;
• depletion of the stratospheric ozone layer, in kg CFC-11e;
• acidification of land and water sources, in moles H+ or kg SO₂e;
• eutrophication, in kg nitrogen eq or kg phosphate eq;
• formation of tropospheric ozone, in kg NOx, kg O3 eq, or kg ethene; and
• depletion of nonrenewable energy resources, in MJ using CML / depletion of fossil fuels in TRACI.

Europe ACP: Option 4 Whole Building Life-Cycle Assessment

For European projects, EN standard 15978 may be used as framework for the Life-Cycle-Assessment instead of ISO 14044 for this credit. Where implementation of EN 15978 conflicts with any of requirements of this credit, the credit requirements prevail, including the life-cycle stages required and treatment of EPD data (See Further Explanation - Incorporation of EPD data in WBLCA Tools). Note that the CML indicators are acceptable per the Further Explanation section of the Reference Guide language of this credit. Projects will still need to meet the individual requirements of the pathway chosen for this credit option.

Further Explanation - Incorporation of EPD data in WBLCA Tools: Combining EPD impacts with WBLCA results shall follow the best practice guidance outlined in Athena Guide to Whole Building LCA in Green Building Programs which stipulates that EPD results may only be combined provided the EPD:

• Has not expired;
• EPD scenarios should be representative of contemporary technologies and/or practice, and the project location;
• Reports all indicators and system boundary information modules required by the WBLCA tool;
• Characterizes the impact categories reported according to the same LCA methodology as the WBLCA tool;
• Can be applied to the study period of the assessment;
• Clearly indicates which product (including manufacturer and product name) or geographical region it reflects in comparison to the industry-wide weighted average results of a material or fuel already available in the tool.

Europe ACP: Whole-Building LCA according to the Level(s) framework

• depletion of the stratospheric ozone layer, in kg CFC-11e;
• acidification of land and water sources, in moles H+ or kg SO2e;
• eutrophication, in kg nitrogen eq or kg phosphate eq;
• formation of tropospheric ozone, in kg NOx, kg O3 eq, or kg ethene

• depletion of the stratospheric ozone layer, in kg CFC-11e;
• acidification of land and water sources, in moles H+ or kg SO2e;
• eutrophication, in kg nitrogen eq or kg phosphate eq;
• formation of tropospheric ozone, in kg NOx, kg O3 eq, or kg ethene

Frequently asked questions

What does it cost?

Cost estimates for this credit

On each BD+C v4 credit, LEEDuser offers the wisdom of a team of architects, engineers, cost estimators, and LEED experts with hundreds of LEED projects between then. They analyzed the sustainable design strategies associated with each LEED credit, but also to assign actual costs to those strategies.

Our tab contains overall cost guidance, notes on what “soft costs” to expect, and a strategy-by-strategy breakdown of what to consider and what it might cost, in percentage premiums, actual costs, or both.

This information is also available in a full PDF download in The Cost of LEED v4 report.

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