Scoring Tool Default Values and Fixed Assumptions
For an asset rating to have meaning in the marketplace, one home must be comparable to another. For home characteristics NOT individually recorded and entered into the Scoring Tool, non-asset related inputs are standardized to a nationally consistent set.
Important differences from Home Energy Saver defaults include:
- Lighting energy consumption is a function of the conditioned floor area.
- Appliance energy consumption is a function of the conditioned floor area and the number of bedrooms.
- The building length and width are fixed at 5:3 ratio with the long wall of the house set as the front wall. The dimension are calculated as a function of the conditioned floor area as detailed on this page.
- Occupancy is a function of the number of bedrooms
- The thermostat schedules are described on this page.
In keeping with the standardized nature of the assessment, predicted energy costs and savings assume state-average energy prices. The Scoring Tool applies a standardized retrofit cost from the NREL National Residential Efficiency Measures Database
and limits recommendations to those achieving a payback time of 10 years or less. As a result, predicted energy use may be different from actual utility bills. The extent of these variations will depend on additional factors such as how the occupant maintains their home, appliance ownership and use, actual number of occupants, and year-to-year weather variations.