Hello,
We are working on a low-rise office building and pursuing LEED CS v2009 for the base-building and LEED CI v2009 for at least one of the tenant spaces. These are separate projects that are being designed simultaneously. I have a couple of questions about the requirements and strategies for tenant sub-metering.
1. The tenant lease spaces will only have electricity, they will not have gas, steam or chilled water. To satisfy the metering portion of LEED CI v2009 EAc3 is is acceptable to provide only a single electric meter for each tenant, or do we need to separately meter lights and receptacle loads?
2. Are we required to meter the HVAC used by the tenant spaces? The building is served by 3 variable volume, CHW AHU's on the roof. These AHU's are ducted down through the building in separate chases but are not dedicated or zoned to any particular floor or tenant space. The conditioned air from the roof-mounted AHU's is distributed to all the various zones and spaces through a mix of fan-powered and VAV terminal boxes. With this type of air distribution, how can we meter HVAC energy use at the tenant level(if this is even required)?
Michael Smithing
Director - Green Building AdvisoryColliers International Ltd.
304 thumbs up
March 28, 2016 - 10:14 pm
The requirements for this credit in CS and CI are different but complementary.
1. You do not need to separately meter lights and receptacle loads to achieve this credit. Each tenant (pursuing LEED CI certification) will need to have an electric submeter. Note that if the building intends to pursue LEED EBOM certification the tenant submeters are not sufficient - EBOM requires submetering on a system level and thus wants lighting and plug loads separately metered.
2. Submetering of HVAC energy is not required (although it is one way to meet the credit requirements. The credit requires that the tenants pay the ACTUAL COST of thermal energy, which can be pro-rated on a per square meter basis. It is important to demonstrate (in the lease) that - in the event the tenant pays a fixed amount monthly for utility services - these payments are reconciled to actual costs on a regular (typically annual) basis. This provides an incentive for the tenant to reduce consumption (which a fixed payment would not.)
Rob Pinkston
Mechanical EngineerMarch 29, 2016 - 11:08 am
Thanks Michael.