White paper
Redefining ROI.
Incorporating human performance into lighting valuation models.
Lighting decisions are made on installation cost, energy use, and payback, and they consistently overlook the most valuable asset in any building: the people inside it. This paper introduces the methodology for pricing what standard ROI models leave out.
Chris Sembroski · Sarah Morgan · Sarah Solbiati, PhD
Presented in Leiden, Netherlands, March 2026
The argument
Value engineering is killing human-centric lighting design
Value engineering cuts lighting specifications after design is complete, targeting the upfront cost of the luminaire, which is less than 2% of lighting's total lifetime value, and ignoring the human performance impact that carries the other 98%. For a typical ten-person lighting design team, the toll looks like this:
86%+
of projects require unpaid value-engineering rework
810+
hours of value-engineering rework a year
$200K+
estimated annual cost of that rework
Inside the paper
Lighting science, translated into financial proof
- Why value engineering targets the fixture (less than 2% of lighting's total lifetime value) and ignores the human performance impact that carries the other 98%
- The hierarchy of circadian synchronizers, and why light dominates it
- A methodology for bringing alertness, sleep quality, error reduction, and long-term health outcomes into the ROI calculation
- Peer-reviewed evidence for productivity, health, and risk-reduction gains across offices, hospitals, and schools
- How to reframe the savings envelope so Total Lifetime Value can be calculated and defended
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The paper makes the argument. The program applies it to your building: see the worked ROI model → or see the whole program →