Your Cameras Know the Building Is Empty. Your HVAC Doesn't.

Rhombus + Claude Series — Tying Into the Enterprise

It’s 8 PM. The floor has been empty for two hours. The lights are still on. The HVAC is still running at its 2 PM setpoint. Every night, every office, every empty room — in aggregate, it’s one of the biggest line items in your facilities budget. And it’s entirely preventable.

The reason this waste persists isn’t that the technology to prevent it doesn’t exist. It’s that the system that knows the building is empty — your cameras — isn’t talking to the system that controls the HVAC. They’re built by different vendors, managed by different teams, and connected only in the sense that they both live in the same building.

Occupancy data is the missing input for smart buildings. When your camera system produces it as structured data, every other system that cares about occupancy can finally use it.

Rhombus already detects and reports occupancy. Most BMS platforms expose a setpoint API. The integration is a short prompt away.

For the developers:

With Claude and the Rhombus plugin:

“Every hour after 5 PM, check occupancy across all floors. For any floor empty more than 60 minutes, send the BMS API a setpoint change to energy-saving mode.”

Claude reads occupancy, the BMS adjusts, the bill shrinks.

The payoff: The same cameras that run your security program now drive your sustainability program. Energy spend drops measurably. No new sensors, no new hardware budget, no new vendor. Just two systems you already own, finally talking to each other.