Retrofit Priority Stack for Existing Buildings

Last verified: August 22, 2026. By Will Tygart.

Do the stack in order unless engineering says otherwise. Most wasted CapEx in existing buildings is a plant replacement that never got metering, controls, or load reduction first.

1. Measure — metering, ESPM hygiene, LL84 as the LL97 spine
2. Controls and operations — schedules, setpoints, BMS basics
3. Load reduction — envelope, lighting, plug loads
4. Efficient thermal — plant optimization, heat recovery
5. Electrification readiness — electrical capacity, heat-pump pathways
6. On-site / off-site clean energy tools — only after load work; document claims carefully
7. Resilience co-benefits — backup, heat resilience (BC playbook)

NYC twist

Run the $268 calculator and 2030 scenarios before major plant decisions so you don’t optimize for the wrong decade. A 2026-compliant building can still be a 2030 problem at the same EUI.

Boards: tie the stack to a resolution and a reserve study, not a single vendor pitch. See the co-op / condo playbook.