Design Development

The baseline exterior lighting power allowance (ELPA) may not take credit for any category which does not have any lighting fixtures in the proposed building, or for any area or width within any category which is not lit in the proposed building, even within the tradable categories. In addition, the lighting for a single building component cannot be counted within two separate categories in the baseline ELPA calculations.

Compliant carpeting is easy to find. Consider purchasing compliant carpet and padding that also has a high recycled content too. This will contribute to MRc4 – Recycled Content as well as EQc4.3.

Durability and performance of carpet that are compliant with this credit should not be an issue, compared with conventional materials.

Low-emitting carpet should not have much of a cost premium, if any. 

Consider using low-emitting carpet and carpet padding.

Simulation is the only way to account during the design phase for daylight designs that have many variables such as the use of lightshelves and light-colored interior finishes. The

Measurement is a low-cost compliance method but may not help to optimize daylight during the design phase. An optimized daylight design can cut down substantially on lighting costs over the long run.

Measurement can account for complex daylight designs but does not help inform the design process. It can only confirm compliance once the space has already been constructed.  At that late phase, it may be too costly to make design changes to bring more floor area into compliance.

Measuring daylighting with handheld light meters can be time-consuming for large areas. Also, you are likely to need to defer this credit to the construction phase LEED submittal so that accurate light readings can be taken with interior walls in place.

Option 3:  Daylight Measurement