EFFICIENCY TARGET – MIXED TYPOLOGY
Example efficiency target calculation for a mixed-Typology project, such as a project combining New and Existing Building Typologies.
Example Building:
*Baseline EUI of 223 kWh/m2/yr
*Required reduction for New Buildings = 70%
*Required reduction for Existing Buildings = 50%
*Total Gross Building Area = 7,600 m2
*Area of existing building = 5,000 m2
*Area of new construction = 2,600 m2
Step 1 – Calculate Target EUI for Each Typology
New Building
- Reduction: 223 kWh/m2/yr * 0.7 = 156 kWh/m2/yr
- Target EUI: 223 kWh/m2/yr – 156 kWh/m2/yr = 67 kWh/m2/yr
Existing Building
- Reduction: 223 kWh/m2/yr *.5 = 111.5 kWh/m2/yr
- Target EUI: 223 kWh/m2/yr-111.5 kWh/m2/yr = 111.5 kWh/m2/yr
Step 2 – Calculate Weighted Average
5000m2 existing/7600 total * 111.5 kWh/m2/yr = 73 kWh/m2/yr
+
2600m2 new/7600 total) * 67 kWh/m2/yr] = 23 kWh/m2/yr
Weighted EUI for the project overall = 96 kWh/m2/yr
EMBODIED CARBON – REDUCTION
The embodied carbon reduction must be shown via the change in total value of embodied carbon in the project, measured in carbon dioxide equivalent (CO₂e) and exported from the approved LCA tool that the project team elects to use.
Step 1 – Calculate the Baseline Embodied Carbon.
Collect embodied carbon data from an approved LCA tool in order to calculate the baseline, including embodied carbon values for all materials within the structure, foundation, and enclosure. The baseline embodied carbon value is the sum of these aggregated quantities. For projects with existing elements, the baseline must include embodied carbon estimates of the in-situ materials.
Step 2 – Calculate the Embodied Carbon of the Project.
Calculate the embodied carbon of the new design, repeating the process above, using the same methodology, but incorporating any low-carbon strategies that were implemented. This results in an embodied carbon value for the new design.
Step 3 – Calculate the Reduction in Embodied Carbon
Calculate the percent change from the value of embodied carbon of the baseline to that of the new design, ensuring a reduction of 20% or greater is achieved.
[(Baseline tCO₂e – Project tCO₂e )/ Baseline tCO₂e] x 100 = Percent Reduction
- tCO₂e Delta (baseline vs project) = Baseline tCO₂e – Project tCO₂e
- Percentage Change (decimal) = (Delta / Baseline tCO₂e)
- Percentage Change (shown as a percent) = Percentage Change x 100
Step 4 – Verify Compliance Determination.
A percent reduction equal to or larger than 0.2, or 20%, meets the 20% reduction requirement.
EXAMPLE CALCULATION
Step 1 – Calculate the Baseline Embodied Carbon
Assume the baseline building design includes:
- Steel superstructure: 340 metric tons CO₂e
- A concrete foundation with reinforcing steel elements: 270 metric tons CO₂e
- Enclosure materials: 150 metric tons CO₂e
This results in a total embodied carbon value of 760 metric tons CO₂e.
Step 2 – Calculate the Embodied Carbon of the Project.
After implementing low-embodied-carbon strategies, the project includes:
- Steel manufactured using renewable energy: 310 metric tons CO₂e
- Concrete mix with less cement per unit volume: 200 metric tons CO₂e
- Enclosure materials with reduced materials and some being locally sourced: 90 metric tons CO₂e
This results in a total embodied carbon value of 600 metric tons CO₂e.
Step 3 – Calculate the Reduction in Embodied Carbon
[(Baseline tCO₂e– Project tCO₂e) / Baseline tCO₂e] x 100 = Percent Reduction
- 760 tCO₂e – 600 tCO₂e = 160 tCO₂e
- 160 tCO₂e / 760 tCO₂e = 0.21 tCO₂e
- 0.21 tCO₂e * 100 = 21%
Step 4 – Verify Compliance
A reduction of 21% from the baseline building design meets the Imperative requirements.
EMBODIED CARBON – INTERIOR PRODUCTS, INDUSTRY BASELINE
Interior materials that have lower than industry baseline must be selected where embodied carbon data are readily available for a product category (A1–A5). There are two pathways by which a product category can meet this requirement:
Path 1 – All Products Used in the Project Fall Below the Industry Baseline
Step 1 – Determine the Industry Baseline for that Product (Baseline Carbon)
Verify interior product type baseline from an ILFI-approved baseline tool.
Step 2 – Determine the Embodied Carbon of the Selected Product (Product Carbon)
Collect data for the selected interior products from an approved database’s product-specific EPD.
Step 3 – Verify Compliance
If Product Carbon < Baseline Carbon, the product is compliant.
EXAMPLE CALCULATION
Here is an example for carpet tile.
Step 1 – Determine the Industry Baseline for that Product (Baseline Carbon)
The industry baseline for carpet tile is 2.0 kgCO₂e/sf.
Step 2 – Determine the Embodied Carbon of the Selected Product (Product Carbon)
All selected carpet tile products have an embodied carbon value of 1.5 kgCO₂e/sf.
Step 3 – Verify Compliance
If Product Carbon < Baseline Carbon, the product is compliant.
Since 1.5 < 2.0, all selected carpet tile products comply.
Path 2 – All Products Within the Category Have a Weighted Average That Falls Below the Industry Baseline
Step 1 – Determine the Industry Baseline for that Product (Baseline Carbon)
Verify interior product type baseline from an ILFI-approved baseline tool.
Step 2 – Determine the Embodied Carbon of the Selected Product (Product Carbon)
- Collect the embodied carbon and quantity (i.e., square footage, cubic yards, linear feet, or percentage) data for each group of interior products in that category.
- Calculate total embodied carbon (e.g., (mass CO₂e/unit) * # units) for each product.
Step 3 – Determine the Weighted Average of the Selected Products Within a Category
Sum the product embodied carbon for all the products within a category and then divide by the total number of units of the products in that category.
Weighted average of selected products within a category = (Embodied carbon of product A + embodied carbon of product B) / Total units of products A and B
Step 4 – Verify Compliance
Ensure the weighted average for the product category falls below the industry baseline.
EXAMPLE CALCULATION
Assume a project has two types of carpets with different embodied carbon amounts per square foot.
Step 1 – Determine the Industry Baseline for that Product (Baseline Carbon)
Carpet baseline is 2.0 kgCO₂e/sf.
Step 2 – Determine the Embodied Carbon of the Selected Product (Product Carbon)
- Carpet A: 2.5 kgCO₂e/sf x 1,000 sf of carpet = 2,500 kgCO₂e
- Carpet B: 1.8 kgCO₂e/sf x 9,000 sf of carpet = 16,200 kgCO₂e
Step 3 – Determine the Weighted Average of the Selected Products Within a Category
Calculate the weighted average for the product category based on amount of material used (i.e., square footage, cubic yards, linear feet).
(2,500 kgCO₂e + 16,200 kgCO₂e) / (1,000 sf + 9,000 sf) = 1.87 kgCO₂e/sf
Step 4 – Verify Compliance
1.87 kgCO₂e/sf < 2.0 kgCO₂e/sf, therefore the project’s carpets’ weighted average is compliant.
