Comprehensive Heating Upgrades for Two-Pipe Steam Systems

Market: Multifamily & Commercial
Type: Steam Systems
Location: New York, NY
Scope of Work: Comprehensive steam heating upgrades including orifice plates, thermostatic radiator valves (TRVs), distribution piping upgrades and central controls.
Total Buildings & Units Completed: ±80 buildings
±12,500 units
Total Square Footage: ±7,500,000
Realized Energy Savings: 15% - 35%


Over the past decade, the Building Optimization, Decarbonization, and Efficiency Team at SWA has worked with over 7.5 million square feet of buildings to design and oversee comprehensive steam heating system upgrades. The following case study provides a high-level overview of the upgrades performed, as well as the average costs and energy savings associated with these projects.

Project Services:

SWA staff worked closely with building maintenance personnel and outside contractors to perform various upgrades to steam heating systems in approximately 80 buildings. SWA also delivered training to building operations staff.

Specifically, project teams targeted the following  for optimization:

  • orifice plates
  • thermostatic radiator valves (TRVs)
  • distribution and dry steam work
  • central plant controls

Cost and Energy Savings:

The graph below shows pre- and post-retrofit heat slopes for a sample of  SWA’s projects. The range of savings is dependent upon factors such as pre-retrofit energy use, scope of work details, and post-retrofit building operation. Construction costs range between $700—$1,500 per apartment. The main variables affecting project cost include the use of in-house building staff versus outside contractors (for apartment labor), as well as the extent of the basement distribution work required.





The realized energy savings for the projects ranged from 15% – 35%, The amount of savings achieved is dependent upon factors such as pre-retrofit energy use, scope of work details, and post-retrofit building operation.


Pre and Post Retrofit Heat Slope Graph


Regulatory Compliance:

New York City’s Local Law 87 effectively requires steam traps to be replaced at least once every 10 years in order to demonstrate compliance. These comprehensive steam heating upgrades eliminate the need for steam traps at the radiators, allowing LL87 compliance in the simplest and most durable manner. In addition, this scope of work can support compliance with the upcoming Local Law 97 , whether trying to minimize on-site emissions to reduce fines or to comply with the prescriptive pathway allowed for rent-regulated buildings.

To learn more about steam system upgrades, read our blog, “Comprehensive Heating Upgrades for Two-Pipe Steam Systems.”