Submetering for Commercial and Multi-Tenant Buildings

A utility meter answers one question: how much did the whole building use? Submetering answers the questions that actually drive cost — which tenant, which floor, which chiller, which compressor, which shift. Energy submetering covers electricity, gas, heating and cooling, steam and compressed air; water submetering covers domestic and process water. The same data platform can carry all of them, which is why most portfolios end up metering more than one utility once the first one pays back.

What submetering is

Submetering means installing meters downstream of the revenue meter the utility owns. The utility still bills the building; the submeters divide that consumption among the people, systems or processes that caused it. That division is used three ways:

• Cost allocation and tenant billing — charging each occupant for what they used rather than for their square footage.
• Operations — finding equipment running out of schedule, leaks, simultaneous heating and cooling, and baseload creep.
• Compliance and reporting — energy codes such as ASHRAE 90.1 and the IECC require separate metering of certain end uses in new construction; see the compliance hub.

Electric, water, gas, BTU and compressed air submetering

Each utility uses a different sensing technology, but they share the same output options and can report into one system.

Electric submetering

Current transformers clip around conductors and a meter calculates kWh and demand. Use a branch circuit monitor such as the Leviton S7100 BCM 24-input to meter a whole panel circuit by circuit, or self-powered wireless sensors such as the Panoramic Power PAN-12 when retrofit labour has to stay low. Browse electric meters.

Water submetering

Positive displacement and multi-jet meters suit small residential and tenant lines; ultrasonic meters cover larger pipe and clamp-on retrofits. In multi-unit residential this is its own discipline — see multifamily water submetering. Browse water meters.

Gas submetering

Diaphragm meters such as the Itron Gallus G4 with pulse output cover tenant and kitchen loads; thermal mass meters such as the Sage Model 51 cover boiler and process lines. Browse gas meters.

BTU (thermal energy) submetering

A BTU meter combines flow and supply/return temperature to measure the heating or cooling delivered to a tenant or air handler on a central plant — the only fair way to split chilled or hot water. The EES-301 ultrasonic BTU meter is a clamp-on option. Browse BTU meters.

Compressed air submetering

In industrial plants compressed air is often the most expensive utility per unit of delivered energy, and metering by header or department exposes leak load and idle demand. See compressed air flow meter selection.

How does submetering work?

Every submetering system, at any scale, has the same four layers. The detail of each is covered on the utility submetering systems page.

• Meters measure one load or supply each and output pulses, Modbus RTU, BACnet or a wireless signal.
• Data collection — a data acquisition server such as the AcquiSuite A8810 or a high-density pulse module reads the meters on a schedule and stores interval data.
• Backhaul — the building LAN, a cellular router, a wireless mesh such as the ModHopper, or a LoRaWAN gateway such as the Milesight UG65.
• Software converts readings into dashboards, alerts, reports and, where needed, bills.

The choice that most affects cost is not the meter, it is how readings get from the meter to the network. A panel full of meters next to a network switch is cheap to connect; fifty water meters spread across a garden-style apartment complex need wireless.

Tenant submetering

Tenant submetering bills each occupant for their own consumption. In commercial property it replaces pro-rata recovery by floor area, which over-charges low users and gives heavy users no reason to change. Typical tenant points are the tenant's electric panel, its domestic water branch and, on central plants, a BTU meter on its chilled and hot water.

• Check the lease first. The lease, not the meter, decides whether consumption can be billed and how.
• Meter at the point of supply to the tenant, not at shared equipment, so readings are attributable.
• Use meters with accuracy appropriate to billing and keep a record of meter serial numbers and multipliers.
• Residential billing is regulated differently and varies by state; the multifamily water page covers the common approaches.

Where each type applies

• Office and retail — electric by tenant panel, BTU by tenant on central plants.
• Multifamily residential — water by unit, sometimes electric and gas.
• Industrial and manufacturing — electric by line, compressed air and gas by department.
• Campuses and healthcare — electric, steam, BTU and water by building.
• Data centres and labs — electric by circuit and rack, chilled water BTU.

See industries for sector-specific guidance.

How a submetering deployment works

• 1. Define the question. Billing, operations or compliance — it sets accuracy and reporting requirements.
• 2. Survey. Panel schedules, riser diagrams and pipe sizes and materials for every point.
• 3. Point list. One line per meter: location, utility, size, output and communication path.
• 4. Select hardware. Meters, data collection and backhaul; pre-wired metering panels cut field labour.
• 5. Install and connect. Your electrician and plumber install; meters are mapped into the data platform.
• 6. Verify and report. Check readings against the utility bill before relying on them.

What it costs to start

Start-up cost is driven by four things: the number of points, the meter types, whether lines and panels can be shut down for installation, and the backhaul. Catalogue meters show list prices on their product pages and on the pricing page. For a building-level figure, send the point list or the building details and we return a scoped bill of materials. Most portfolios start with the largest or least understood load, prove the data, then extend.

Choosing who to work with

If you are comparing providers for water specifically, read how to choose a water submetering company.