Base Case
EPIC assesses the efficacy of carbon reduction measures in relative terms as a reduction in the carbon emissions from a base case building. The base case building is a building determined from a set of conservative assumptions which represent a newly constructed project in which no efforts have been made to reduce carbon emissions. The base case provides a means of comparison for evaluating carbon reduction measures. The building's form is not parameterized; the building is assumed to be an extruded square.
When the base case form is filled, click the "Save Base Case" button at the bottom of the form to save the base case and generate the base case figure and table.

Project Information

Project name. Select a name for your project. This name will appear on graphics generated by EPIC and will be the name of the project on the EPIC website.
Project Location. The United States ZIP Code in which the project is located.
Projected year of completion. The year that construction is completed and building operation begins. This is the year to which construction emissions are attributed and the EPIC model begins calculating operational carbon emissions.

Building Structure

Primary structural system. The base case structural system, selected from the following:
  • Steel frame. A structural system comprised of columns, beams, girders, and decking constructed from steel structural members connected with rigid or pin joints.
  • Reinforced concrete. A structural system comprised of columns, beams, and slabs of concrete reinforced with steel that provides tensile strength.
  • Hybrid concrete/steel (high-rise). A structural system that combines rigid steel frames with concrete columns, beams, and slabs. These hybrid structures are more materially intensive and may be used when there are significant seismic loads, in high-rise buildings, or for programs with very high live or environmental loads.
  • Wood frame. A structural system comprised of dimensional lumber, plywood sheathing, and reinforced concrete cores and podiums.
  • Comprehensive mass timber. A structural system comprised of massive beams, panels, and columns, often assembled by aggregating many smaller timber elements. This approach assumes that timber elements are aggressively substituted for other structural materials.

Building Use

Primary Use. The CBECS category most reflective of the project’s main use. This is used to determine the building's energy use and its structural requirements.
Secondary Use. If the primary use comprises less than 100% of the program, a secondary program may be selected for the remainder. This program will affect the EUI (resulting in a ‘blended EUI’) but will not affect the building’s structural system.

Building Floor Area

Number of aboveground floors. The number of building floors above grade. These floors will be assessed using the selected structural system.
Number of belowground floors. The number of building floors below grade. These floors will be assessed as having a reinforced concrete structural system.
Floor area per aboveground floor. The area, in square feet, of the average aboveground floor. To determine cladding and roof area, the floor is always assumed to be square.
Floor area per belowground floor. The area, in square feet, of the average belowground floor. The floor is always assumed to be square.

Site and Landscaping

Previously developed site? If the site is not previously developed, it is a greenfield site and the project incurs an emissions penalty for the site disturbance. The magnitude of this penalty is equivalent to the site area’s sequestration potential with low-sequestration plantings.
Site Area. The total site area (building and landscaping). To accommodate the base case building, the site area should not be lower than the average aboveground floor area.
Planted Area. The planted area located outside the building's footprint. This input cannot be less than the site area less the average aboveground floor area.

Donut Chart

The base case is summarized with a donut chart showing the proportion of embodied, operational, and sequestered carbon emissions over 30 years.
The base case donut chart summarizes the emissions associated with the base case building.
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Project Information
Building Structure
Building Use
Building Floor Area
Site and Landscaping
Donut Chart