Check energy-code (LPD) compliance

Energy codes cap how much lighting power you can install per unit of floor area. Watching the LPD readout as you design keeps you from over-lighting a space and having to strip fixtures out later — and it reads in whichever unit system you work in.

1. Select an area with fixtures

   Lighting Power Density (LPD) is a per-area measure, so select a calculation area that has fixtures contributing to it. The energy readout appears with the area's properties in the right panel.

2. Read the watts-per-area figure

   OpenLumen totals the input watts of the fixtures over the area and divides by its size to get a power density. It's shown in your active units — W/ft² in Imperial, W/m² in Metric — so the same design reads correctly either way.

3. Understand the compliance status

   The figure is compared against the lower (stricter) of the ASHRAE 90.1-2019 and IECC 2021 limits for the selected space type. You'll see one of three states:

   • LPD Compliant (green) — at or under the limit.
   • LPD Near Limit (amber) — within 10% over the limit.
   • LPD Exceeds Limit (red) — more than 10% over.

   A tooltip breaks out both the ASHRAE and IECC limits and the code-table sections they come from.

4. Treat it as guidance, not a stamp

   The check carries a *"Guidance only — not official compliance"* note for a reason: it's a fast sanity check on your design, not a substitute for an energy model or a code official's review. Use it to catch an over-lit space early, then adjust fixture count, wattage, or the per-type output multiplier to bring it in line.