EA 07-04 indicated that buildings with central DHW systems must submit a project-specific CIR. Can the TAG provide some information about what is considered standard practice and what kinds of improvements might be eligible for credit in multi-family buildings with central DHW systems? Similarly, what should be considered standard practice - for comparison? Is a thermostat-controlled recirculation system standard practice or an efficiency upgrade? What are reasonable plumbing run lengths - from the central recirculation loop to the fixtures in each unit - that may be worthy of credit?
Multifamily projects with a central DHW system can earn credit if they install a central demand-controlled recirculation loop that is insulated to at least R-4.
Updated 10/1/13 for rating system applicability.