# Types of Submeters: Water, Gas and Electric Meters Compared

Source: https://submeter.com/submetering-meters/
Publisher: National Exemption Service (NES), https://submeter.com. Last reviewed September 2026.

Water, electric, gas and BTU submeters compared: what each measures, who installs it, how it is read, and how to choose the right meter for your building.

## What types of submeters are there?
The main types of submeters are water submeters, electric submeters, natural gas submeters, and BTU or heat submeters. Water submeters include positive displacement, multi-jet, and solid-state ultrasonic meters that measure volume in gallons or cubic feet. Electric submeters are solid-state kilowatt-hour meters meeting ANSI C12.20 standards. Gas submeters use diaphragm or rotary mechanisms measuring cubic feet, which are converted to therms for billing. BTU meters combine flow sensors and temperature probes to track energy used by hydronic heating and cooling systems. All types record individual tenant utility consumption past the central utility meter.

Owners of apartment communities, condominiums, and mobile home parks with 80 or more units face large utility bills each month. Different buildings require different meters, communication networks, and reading schedules to divide these bills fairly. You will learn how each meter type works, what the hardware costs to run, and how to choose the right setup for your property.
## How a submeter differs from a utility meter
A utility meter belongs to the city or local utility company. It sits at the property boundary, measures the total water, gas, or power entering the site, and generates a single master bill.
A [utility submeter](https://submeter.com/master-metering-vs-submetering/) sits past that master meter on a dedicated line serving an apartment, condo, or mobile home lot. The submeter records only what that specific unit uses. Your local utility does not install, read, or repair these indoor meters. That hardware belongs to the property owner.
NES never bills residents more than the master bill. Common-area use from the clubhouse, pool, irrigation, and shared laundry rooms stays with the owner.

## Types of submeters by utility
Different utilities use distinct mechanical parts to measure flow. Sizing a meter incorrectly or picking the wrong design leads to broken parts, unrecorded slow leaks, and disputed bills.
### Water submeters
A [water submeter](https://submeter.com/what-is-water-submetering/) measures volume in gallons or cubic feet. Plumbers size these meters to fit unit supply lines, which are typically 5/8-inch, 3/4-inch, or 1-inch pipes in multifamily buildings. Sizing matters. An oversized meter misses small drips from a leaky toilet flapper, while an undersized meter chokes water pressure at the shower. Every meter undergoes testing for accuracy before it goes into service.
Three designs handle most water submetering:
![Row of three water meters with dials mounted on supply pipes.](https://submeter.com/wp-content/uploads/2019/05/CostofInstallingSubmeters.jpg)
Water submeters are sized to each unit's line and tested for accuracy before they go into service.
- Positive displacement meters. An oscillating piston or nutating disc moves inside a measuring chamber. Water fills and empties the chamber, turning a mechanical register with each cycle. These meters catch low flow rates well, which makes them common on indoor lines.
- Multi-jet meters. Water flows through internal ports to spin an impeller wheel. The speed of the wheel matches the flow of the water. These meters tolerate mineral scale and grit, making them practical for outdoor meter pits in mobile home parks.
- Ultrasonic meters. These solid-state meters have no moving parts. Sound waves travel between acoustic sensors to track flow speed. Without gears to wear down, ultrasonic meters keep their factory accuracy for years, though they cost more upfront.
### Electric submeters
An [electric submeter](https://submeter.com/submetering-electric/) measures power in kilowatt-hours (kWh). Modern units are solid-state digital devices that meet ANSI C12.20 standards. Licensed electricians wire them directly inside or next to unit breaker panels.
These meters handle 120, 208, or 240-volt service in single-phase or three-phase setups. Current transformers clamp around incoming power cables to track electrical load. Many models record interval data every 15 minutes, showing daily peaks in tenant demand.
![A round electric meter mounted on a wall.](https://submeter.com/wp-content/uploads/2019/05/Submeters.jpeg)
Electric submeters measure the kilowatt-hours each unit uses.
### Gas submeters
A [gas submeter](https://submeter.com/submetering-natural-gas/) tracks the volume of natural gas or propane burned by stoves, unit water heaters, and furnaces. The meter records volume in cubic feet, and billing software converts that number into therms using the heat factor from your utility bill.
Gas meters meet ANSI B109 standards and come in two styles:
- Diaphragm meters. Flexible internal bladders fill and empty as gas moves through valves. This is the standard design for residential gas lines.
- Rotary meters. Machined impellers spin as gas passes through a compact chamber. Plumbers install these where wall space is tight or gas volume is high.
Because gas requires strict safety precautions, these installations need dedicated venting and licensed pipe fitters.
### BTU and heat meters
A [BTU meter](https://submeter.com/submetering-hot-water/) measures thermal energy instead of fluid volume. Properties with central boilers, chillers, or hydronic loops do not have separate water heaters or furnaces inside each unit.
A BTU submeter tracks fluid volume alongside the temperature difference between supply and return pipes. An internal processor calculates British Thermal Units used by the apartment. This lets the property split central heating and cooling costs based on actual use.
| Meter type | What it measures | Units billed | Who installs | Notes |
| --- | --- | --- | --- | --- |
| Water submeter | Fluid volume | Gallons or cubic feet | Licensed plumber | Positive displacement, multi-jet, or ultrasonic |
| Electric submeter | Electrical energy | Kilowatt-hours (kWh) | Licensed electrician | Solid-state, ANSI C12.20 certified; uses CTs |
| Gas submeter | Gas volume | Cubic feet (converted to therms) | Licensed gas fitter or plumber | Diaphragm or rotary; ANSI B109 certified |
| BTU / heat meter | Thermal energy | BTUs or therms | HVAC technician or mechanical plumber | Measures fluid flow and temperature change across pipes |

## Submetering equipment beyond the meter
Meters alone do not complete a submetering system. Manual walk-by reads take too much staff time, so properties rely on wireless networks to collect data.
![A water meter installed on supply piping next to valves and pressure gauges.](https://submeter.com/wp-content/uploads/2024/04/NESWaterMeter.jpeg)
The meter is one piece. A transmitter, repeaters and a gateway carry its readings to the billing software.
A wireless submetering network uses three hardware components:
- Transmitter. A small battery-powered radio connects to the meter register. It sends consumption pulses across the property using radio frequencies.
- Repeater. Concrete walls, steel studs and subfloors weaken radio signals. Repeaters in halls or breezeways pick up faint signals and pass them along.
- Gateway. A central receiver gathers data from every repeater. It bundles the readings and transmits them to billing software over a cellular link, without touching property Wi-Fi.
Not sure which meters your building needs?. Send your unit count and 12 months of bills. A specialist replies within one business day.

## Methods for measuring submetering usage
How you collect readings determines how fast you spot leaks.
| Reading method | How it works | How often you get data | Leak detection capability |
| --- | --- | --- | --- |
| Manual reading | Staff walk the site, inspect registers, and write numbers on clipboards or mobile apps. | Once per month | None. A running toilet can run unnoticed for weeks. |
| Drive-by (AMR) | A vehicle with a receiver drives the property roads to pick up short-range radio signals. | Once per month | Very low. The system only collects data on the day the vehicle visits. |
| Fixed network (AMI) | Repeaters and a cellular gateway transmit wireless readings automatically. | Multiple times per day | High. Continuous flow alerts flag running toilets within a day. |
At NES, we install wireless, fixed-network systems. Our meters report readings several times a day through the [MyReads leak detection](https://submeter.com/myreads-leak-detection/) portal. When a toilet flapper sticks open, the software flags continuous flow so your maintenance team can fix it quickly. That stops high water waste before the utility sends its monthly bill.

## Which submeter is best for your property?
Every property has unique plumbing and wiring. Choosing your setup involves several practical steps:
- Check plumbing access. Water submetering works best when each unit has a single cold-water line in an accessible closet. When a water heater must be pulled out to reach the pipe, installation costs rise noticeably.
- Avoid proprietary hardware. Some vendors lock meters to their own private reading software. If their customer service drops, you cannot change billing providers without buying new meters. NES installs nonproprietary meters you own, backed by a warranty.
- Pick network types by leak risk. Underground lines and aging indoor plumbing need fixed wireless networks rather than drive-by reads. A single running toilet can waste thousands of gallons before an inspector visits.
- Look at your utility bills. If water is your largest bill, meter cold water lines first. When winter heating runs on unit electric baseboards, electric panel meters make more sense.
- Review local regulations. State, county, and city codes govern resident billing. Texas requires registration with the Public Utility Commission of Texas, while North Carolina requires a certificate from the North Carolina Utilities Commission. When local rules or shared plumbing risers rule out submeters, ratio utility billing (RUBS) allocates bills by occupant count or square footage without new hardware.

## Keeping submeters accurate: testing, repair, and replacement
Meters run constantly for years, so hardware needs regular upkeep.
Plumbing meters are tested at the factory to confirm accuracy before installation. Over time, mineral scale and mechanical friction cause water meters to slow down. Slow meters do not overbill residents, but they under-record volume and reduce your utility recovery. Electronic meters have fewer moving parts, but internal lithium batteries and radio transmitters eventually run down.
NES installs nonproprietary meters you own, backed by a warranty. When a battery dies or a transmitter stops reporting, our team handles repairs and [meter equipment replacement](https://submeter.com/meter-equipment-replacement/). Routine maintenance protects monthly cost recovery across every building.

## Questions
**Which water submeter is most accurate?**
Positive displacement and ultrasonic meters provide the best accuracy in apartments. Positive displacement meters register slow, low-volume leaks from running toilets or dripping faucets. Ultrasonic meters maintain factory calibration longer because they have no internal gears to wear down or clog with lime scale. Learn more about testing tolerances in our guide on whether submeters are accurate.

**Who owns the submeters?**
The property owner owns the submeters. Unlike city utility meters, submeters are private hardware installed on building plumbing or electrical panels. NES installs nonproprietary equipment with a warranty, and you own the meters outright. You are never locked into NES if you ever decide to switch providers.

**How long do submeters last?**
Many years, but not forever. Mechanical water meters slow down as mineral scale and wear build up, and the batteries in solid-state meters and transmitters eventually run down. A fixed network shows you which ones are slipping, so you replace meters as they fail instead of all at once.

**Can existing meters be read by a new provider?**
Yes, as long as the meters are nonproprietary. If your property has functional meters from established manufacturers, a new provider can read them without installing new hardware. If your current billing service is slow to respond, explore how to switch submetering providers while keeping your existing meters.

**Do I need a meter on the hot and cold line?**
It depends on how the building was plumbed. If an apartment has its own water heater fed by a single incoming cold pipe, one cold-water meter is enough. Buildings with central boilers often route separate hot and cold riser lines into each kitchen and bathroom, which requires multiple meters per unit.

**What happens when a meter or transmitter fails?**
A fixed network catches equipment failures quickly. If a transmitter stops sending data or a register reports erratic numbers, our billing software flags the unit. NES repairs or replaces the failed part. How a missed read is billed depends on state rules, and our compliance team sets that up for your property.