Water Meters
Water meters measure the volume of potable water passing through a service line so utilities can bill for usage and property owners can track consumption. They install between the curb stop and the building, usually in a meter setter inside a meter box or in a basement, and register flow in gallons or cubic feet.
Residential water meters serve single-family and small multifamily services, while commercial water meters serve larger buildings with higher or variable demand. Common meter types include positive displacement, multi-jet, single-jet, ultrasonic, turbine, and compound designs, used with registers, remote-read hardware, and water meter accessories such as couplings, gaskets, and flanges. Positive displacement and multi-jet designs cover most small services, while turbine, compound, and ultrasonic meters handle larger flows. Selection depends on service size, flow range, register units, installation conditions, and the requirements set by the local water utility.
Water Meter Products
Water meters fall into groups by measuring principle and function. Knowing each group helps contractors match water meter equipment to the service size and the utility's reading method.
Positive Displacement Meters
Positive displacement meters measure flow by filling and emptying a chamber of fixed volume with a nutating disc or oscillating piston. They hold accuracy at low flow rates, which makes them the standard choice for residential services.
Multi-Jet and Single-Jet Meters
Multi-jet meters direct water through several ports to spin an impeller, which spreads wear evenly. Single-jet meters use one jet in a compact body. Both are inferential meters built for small services, submetering, and indoor installs where space is limited.
Ultrasonic Meters
Ultrasonic meters measure flow by timing sound pulses sent upstream and downstream through the water. With no moving parts in the flow path, they keep low-flow sensitivity over time, and many include electronic registers with leak and reverse-flow alerts.
Compound and Turbine Meters
Turbine meters measure steady, high flows in commercial and irrigation services. Compound meters pair a turbine with a smaller low-flow meter and a changeover valve, so they register both peak demand and small draws in apartments, schools, and hotels.
Registers and Remote-Read Systems
The register displays and records consumption. Direct-read registers are read on site, while encoder and pulse-output registers connect to AMR or AMI radio units that form water meter systems for drive-by or fixed-network reading. Sealed, pit-rated registers resist moisture in flooded boxes.
Water Meter Accessories
Meters and related parts are listed in the Water Meter & Accessory category. Accessories used with a meter typically include couplings, gaskets, flanges, remote registers, and pulse-output modules. These water meter supplies connect the meter to the setter and seal each joint.
How Water Meters Work and Where They Install
How a Meter Measures Flow
The main water meter components are the main case, the measuring element (disc, piston, impeller, turbine rotor, or ultrasonic transducers), and the register. Larger meters often add an upstream strainer to protect the measuring element from debris.
Where the Meter Sits in the Service Line
A residential service typically starts with a tap at the main through a corporation stop, runs through service tubing to a curb stop, and ends at a meter setter inside a meter box. The setter holds the meter at the correct height and alignment and includes valves for removal. In many areas the utility sets and owns the meter, while the contractor installs the service line, setter, and box to utility specifications.
Residential, Commercial, and Submetering Uses
Residential services use small positive displacement or multi-jet meters. Commercial services use larger turbine, compound, or ultrasonic meters. Submeters and irrigation deduct meters are common water meter solutions for multifamily, mixed-use, and irrigated properties, where the utility or state rules allow them.
Key Specifications and Planning Steps
Size and Lay Length
Meter size refers to the connection and capacity, such as 5/8" x 3/4", 3/4", or 1" for residential services. Lay length is the overall length from inlet to outlet connection. Measure the existing gap and confirm the connection type before ordering a replacement.
Register Units and Reading Method
Registers read in US gallons or cubic feet. Match the unit and reading method to the utility's billing and meter reading system. One cubic foot equals about 7.48 gallons.
Materials and Lead-Free Standards
Main cases are built from lead-free bronze or copper alloy, polymer, or cast iron on some larger meters. For potable water service, check product documentation for certification to NSF/ANSI/CAN 61 and NSF/ANSI 372.
Pit Installation and Freeze Exposure
For outdoor pits, use pit-rated registers sealed against flooding, set the box to local frost-depth practice, and use insulated lids where freezing is common. Many residential meters include frost-protection bottom plates designed to break before the main case.
Choosing the Right Water Meter
Selecting water measurement equipment starts with the utility, since many utilities specify the approved meter type, size, register, and reading system. Next, size water meters to expected flow demand rather than pipe size alone. A home with irrigation or high-flow fixtures needs a meter whose operating range covers peak demand without excess pressure loss. For buildings with widely varying demand, compare compound and ultrasonic options. Choose direct-read, encoder, or pulse-output registers based on how the meter will be read, and pit-rated models for outdoor boxes. Confirm lay length, connection type, and lead-free certification before ordering. These checks keep water metering systems accurate and readable over the meter's service life.
Frequently Asked Questions
Where can I buy residential water meters in common service sizes?
Residential water meters are available through waterworks and plumbing supply channels in common service sizes, most often 5/8" x 3/4", 3/4", or 1". Confirm the size, type, and register your utility requires before ordering for a new service.
What water meter supplies do I need for a complete meter set?
A typical residential meter set includes a corporation stop at the main, service tubing, a curb stop, a meter setter, a meter box, the meter, and couplings and gaskets. These water meter supplies vary by utility, so check local specifications for sizes and connection types.
What are the main types of water meters?
The main types of water meters are positive displacement, multi-jet, single-jet, and ultrasonic for smaller services, plus turbine and compound meters for larger services. Positive displacement meters measure fixed volumes, jet meters infer flow from impeller speed, and ultrasonic meters time sound pulses through the water.
How do positive displacement and compound water meters differ for commercial service?
A positive displacement meter measures flow through a single chamber and holds accuracy at low flows. A compound meter combines a turbine for high flows with a smaller low-flow meter and switches between them, which suits commercial water meters serving buildings with widely varying demand.
How do I choose between gallons and cubic feet for a water meter register?
Match the register unit to the utility's billing and meter reading system. Neither unit is more accurate. One cubic foot equals about 7.48 gallons, so a mismatched register creates billing and reading errors.
How do I check lay length before ordering a replacement water meter?
Measure the overall length between the existing inlet and outlet connections, and confirm the connection size and type. The replacement meter's lay length must match that gap, or the setter or couplings will need to be changed.
How do I size a water meter for a home with irrigation?
Size the meter to expected peak flow demand, not pipe size alone. Add the demand from irrigation zones and high-flow fixtures, then choose a meter whose operating range covers that peak without excess pressure loss. Check the utility's sizing requirements before ordering.
Who is responsible for installing and setting a water meter on a new residential service line?
Responsibility varies by utility and jurisdiction. In many areas the utility supplies, sets, and owns the meter, while the contractor installs the service line, curb stop, meter setter, and meter box to utility specifications. Confirm the division of work with the local utility before starting.
What lead-free certifications should I check when selecting a water meter for potable water?
Check product documentation for certification to NSF/ANSI/CAN 61, which covers health effects of drinking water components, and NSF/ANSI 372, which covers lead content. Local codes and utility specifications may list additional requirements.
What should I consider when installing an outdoor water meter in a pit exposed to freezing or water intrusion?
Use a pit-rated or sealed register that resists moisture in a flooded box. Set the meter box to local frost-depth practice, use an insulated lid where freezing is common, and confirm the meter includes frost protection, such as a bottom plate designed to break before the main case.
What are the main water meter components?
The main water meter components are the main case, the measuring element, and the register. The measuring element can be a disc, piston, impeller, turbine rotor, or ultrasonic transducers. Larger meters often add an upstream strainer to protect the measuring element.
How do water metering systems with AMR or AMI transmit readings?
An encoder or pulse-output register sends the reading to a radio unit. In AMR water metering systems, readers collect data by driving or walking past the meter. AMI systems send readings over a fixed network on a set schedule, without a site visit.
What water meter accessories are used with a meter?
Common water meter accessories include couplings, gaskets, flanges, remote registers, and pulse-output modules. They connect the meter to the setter or piping, seal each joint, and extend reading options to remote or automated systems.
Can I add a submeter to an apartment building or an irrigation line?
Yes, where the utility and local rules allow it. Submeters track individual units or tenant spaces, and irrigation deduct meters measure water that does not enter the sewer. If readings are used for billing, check state requirements for approved meters.
What do contractors need to know about a water meter setter and meter box on a new residential service?
The meter setter holds the meter at the correct height and alignment and includes valves for removal. The meter box protects the setter and meter and provides reading access. Both should match the meter size and follow utility specifications for depth, materials, and placement.