Sub-metering is the implementation of a system that allows a residents welfare associations (RWA) or Property Management Companies to bill residents for water or any other utility measured on usage. The approach makes use of individual meters as per the relevant utility.The concept of sub-metering in USA was "invented" sometime in the 1920s, when many of their laws currently affecting sub-metering were written. However, sub-metering really did not take a hold until the late 1980s, with the ever increasing costs associated with utilities and a society more aware of environmental conservation.Studies have been done in other countries to better understand how billing methods affect water consumption patterns, it is found
- That the residents who pay for their water use less.
- Billing type is a more important influence on consumption patterns than either the cost of water/sewer or the age of the building.
- There are two main methods of allocating the charges to the resident
Sub-Metering : Sub-metering a master-metered building is unlike virtually any other energy conservation measure that can be undertaken by a building owner. Sub-metering as a conservation measure enlists both management/association and residents in the effort and generally produces a conservation savings of 20 to 40%. With advancements made over the past years, there now exists a wide range of technologies available to accomplish sub-metering for water, gas or electric for almost every property configuration. A typical sub-metering system consists of a meter to measure usage of a specific utility for each unit and a wireless system to transmit the data to a central computer to allow for remote reading. A third party billing company is normally used to read the meter data and format a bill that is sent to the tenants.Through Sub-metering:
- Residents Pay for Actual Usage
- Reduce utility usage 20% - 50%
- Less legal complication
- Enhances property value
RUBS (Ratio Utility Billing System) : RUBS is a method of allocating water and sewer costs in apartments, condominiums, offices, shopping centers and other multi-housing communities. The actual utility bill for the property is distributed to each resident based on an allocation formula. Factors in the formula can include one or a combination of the following:
- Number of occupants
- Square footage
- Number of bathrooms
- Allocation is Consistency
- Cost – Little or no upfront investment
- 15% to 20% reduction in usage
- May be implemented where Sub-metering is difficult
- Excellent means of starting program
RUBS Vs Sub-meteredAdvances in metering technology have made it possible to economically convert multi-unit properties to individual metered service using sub-meters. However, the plumbing configuration in many properties makes it too costly, and in some cases, impossible to install individual sub-meters.RUBS is a way to help residents understand the true cost of utility service in properties where meters cannot be feasibly installed. By allocating a portion of the property utility costs, residents can see the connection between usage and cost. By separating utility costs from rent, water conservation is encouraged. This helps keep resident total housing cost as low as possible and also promotes environmental conservation.