NYC LL97: Prescriptive ECM’s

Apr 8, 2024

New York City’s Local Law 97 (LL 97) is currently in effect. An eligible building’s greenhouse gas (GHG) emissions (based on energy usage) counts against its limit now. There is no question that LL 97 will have major impacts on the bottom lines of many buildings and companies. Six-figure annual fines are expected as early as 2025.

Last minute changes to LL 97 this past December introduced the possibility, for certain buildings, of an alternative, prescriptive path to compliance, independent of what one’s GHG emissions are. Final LL 97 consists of two articles. Article 320 is the “traditional” LL 97, requiring a subject building to compile total energy usage, compute GHG emission intensity, and compare it to a limit. Article 321 is specifically for “affordable housing” and religious institutions. Such buildings may comply using the Article 320 track or could elect to follow a second option, a prescriptive path. Instead of compiling energy usage data and comparing to a limit, the prescriptive path allows the building to automatically comply with LL 97 if it implements all of 13 listed energy efficiency practices. It is likely that most buildings already do several of these. However, many would be new and require an investment of resources to implement. Thus, it should be noted that although the prescriptive path allows automatic compliance with LL 97, it may be quite expensive to implement all of the listed practices and technologies. Thus, an Article 321-subject building should be careful in determining which path to take.

The 13 prescriptive measures that must all be implemented are as follows:

  • Adjust temperature setpoints that make sense
  • Repair heating system leaks
  • Clean and maintain heating system (at least annual servicing)
  • Install temperature controls, such as thermostatic radiator valves (TRVs), or radiator enclosures; controls over the steam or hot water that enter radiators
  • Insulate all pipes that carry steam or hot water (including condensate return) and there is no restriction on size of pipe (includes piping under 3” in diameter)
  • Insulate steam condensate tank and hot water tanks
  • Install heating system sensors and boiler controls. Sensors in at least 25% of units that feedback to boiler need for steam or hot water.
  • Replace or repair steam traps. Test representative percentage. Replace failed ones. If >20% fail, then all steam traps must be tested and replaced if failing.
  • Install or upgrade steam system master venting to ensure air is not trapped.
  • Lighting upgrade is required in common areas to at least meet the NYC code at the time of the most recent installation.
  • Air sealing. Confirm that all portions of building envelope (windows, doors to outside) are properly sealed of leaks; otherwise have weatherstripping installed.
  • Install ventilation exhaust fan air timers, so they do not operate 24/7, if allowed.
  • Install radiant barriers behind radiators, so that heat is not absorbed by walls and is directed to the room.

As you can see, many are new technologies that will require planning and spending of money to implement (although many can be covered, in part, by incentive programs). The 13 measures must be implemented and approved by an appropriate professional agent. This is due by the end of this year. The NYC DOB understands that meeting such a tight deadline may be problematic. It has stated that it will allow extensions if the building demonstrates distinct progress in implementing these measures.