Water submetering for duplexes, triplexes, and quadplexes

Why SimpleSUB Water is the unequivocal answer for small multifamily submetering

If you own or manage a duplex, triplex, or quadplex, you already know how quickly water can turn into a headache.

One unit might have a single quiet resident, while another has four people who love long showers. Maybe you have a large main house and a small carriage house sharing the same line, but everyone pays the same “water included” rent. Maybe the irrigation system or hose bib is tied to one unit’s plumbing, and you are constantly arguing about what is “fair.”

On top of that, there is always the nagging worry about hidden leaks. You only find out something is wrong when the city bill shows up and it is much higher than usual.

It all adds up to the same core problem:

When water is bundled into rent at a small multifamily property, the people who use the most often pay the least, and the owner or manager gets stuck with the difference.

Water submetering fixes that. Instead of one opaque bill from the city, you can see how much each unit actually uses, split the cost accordingly, and encourage everyone to be more responsible with water.

You probably already understand that much. You are here because you want a practical solution that works month after month, not just a theory.

You want:

• Separate water usage for each unit
• A fair way to split your existing utility bill based on real usage
• A repeatable process that does not become a second job

There are lots of ways to get part of the way there. You can buy cheap in-line meters from Amazon. You can try WiFi-connected gadgets that clamp onto the pipe. You can talk to large submetering and billing providers that are really built for very big communities.

SimpleSUB is different. It is the best choice for duplexes, triplexes, and quadplexes and is also proven at scale. The same technology that works for larger apartment communities, HOAs, and mobile home parks also works incredibly well for smaller buildings.

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The submeter system you're looking for (even if you don't know it yet)

Most owners and managers are not out shopping for “ultrasonic over-the-pipe cellular submeters.” You are shopping for a simple, repeatable outcome:

“I want my water bill to be fair, predictable, and easy to pass through to each unit, without giving myself a new monthly job.”

Underneath that, there are three core pieces you need:

1. A water submeter for each unit: The physical device that measures how much water flows through the pipe that feeds that unit.‍
2. A way to get meter data online automatically: So you are not standing in a basement every month reading dials and typing numbers into a spreadsheet.‍
3. A billing-friendly portal: Somewhere you can:
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   1. Enter your actual city water bill
   2. Decide how to treat fixed fees, sewer, and taxes
   3. Let the system split costs by usage
   4. See clearly what each unit owes

Bonus points if you can keep good records and reduce disputes when questions come up.

SimpleSUB Water covers that entire chain, from water line to billed amount. Here's what that looks like.

SimpleSUB: the complete package for submetering duplexes, triplexes, and quadplexes.

1. Over-the-pipe install most owners can handle

SimpleSUB meters clamp around the outside of the pipe. Installing them is usually:

1. Identify the cold water line feeding a unit
2. Place the meter on the pipe
3. Tighten the included zip ties
4. Press the "play" button, and wait for two green lights.

There is no cutting pipe, no soldering, and no invasive re-plumbing.

That means:

• No need to shut off water to the entire building
• No new fittings that could introduce leaks
• No multi-hour plumber visit just to add meters

For most duplexes, triplexes, and quads, this is true DIY. If you prefer to delegate, any handyman or plumber can install quickly because there is no pipe cutting involved.

Install once, and you have the foundation for years of accurate billing.

2. Built-in cellular connection (no WiFi required)

A lot of “smart” devices assume there is strong WiFi everywhere. Small multifamily properties rarely cooperate with that assumption.

SimpleSUB meters use built-in cellular connectivity to send data to the cloud. That means:

• No risk that tenants changing their internet plan will knock your meters offline
• No routers to configure
• No worrying about whether WiFi reaches the crawlspace or meter closet

If the meter can see the cellular network, it can send data. You are not tying your metering to anyone’s home WiFi.

For off-site owners and managers, this is particularly important. You do not want to drive over just because someone reset a router.

3. Battery powered (no outlet needed at the install point)

SimpleSUB runs on internal battery power, so you do not need an electrical outlet where the meter sits.

That means:

• No paying an electrician to add new outlets
• No extension cords in tight mechanical spaces
• Freedom to pick the best spot on the pipe, not the closest plug

Physical install becomes a matter of choosing a clean section of pipe, not an electrical project.

4. You don't have to guess your exact pipe type and size

With many metering systems, you have to figure out in advance whether your pipes are copper, PEX, CPVC, or galvanized, and what the exact diameter is. SimpleSUB is designed to work with a wide range of common residential pipe materials and sizes, and our Automatic Pipe Detection (APD) feature helps the system dial in the right settings without you becoming a plumbing expert.

SimpleSUB does not support every pipe type or layout in existence, so if you have an older building, mixed materials, or anything unusual, it is always best to check with us before you order. APD handles a lot of the pipe details for you, but we will confirm whether your specific setup is a good fit.

If you want the technical deep dive, you can read more in our APD article.

5. Daily readings that are tuned for billing and leak detection

SimpleSUB takes readings daily and sends them to your online dashboard.

Daily data is the right level of detail for most small multifamily properties:

• It is granular enough to catch leaks and odd usage patterns
• It lets you compare units sensibly over time
• It keeps the data set manageable, so you are not drowning in minute-by-minute charts you never use

You are not buying a laboratory instrument; you are getting consistent, practical information that helps you protect your bottom line and allocate water fairly.

6. Billing tools included (not as an afterthought)

This is where SimpleSUB really separates itself from WiFi gadgets and cheap meters.

Every billing period, your workflow looks like this:

1. You receive your water bill from the city
2. You log into the SimpleSUB portal
3. Enter the bill total, plus any fixed fees or sewer charges you want to include
4. SimpleSUB pulls usage data for each meter and splits the bill by the rules you set
5. You see a clear breakdown showing what each unit owes

You can:

• Export or copy those amounts into your existing rent collection system
• Share line items with residents if they have questions
• Keep a clean history in case you ever need to look back

Instead of downloading data and maintaining your own spreadsheet formulas, you let the system do the tracking and math, and you focus on decisions and communication.

Install once, and month-to-month billing becomes a repeatable routine instead of a chore.

Important: SimpleSUB provides tools to measure usage and calculate allocations, but it does not provide legal advice. Before billing residents for water, you should review all applicable local, state, and utility regulations (including any submetering or RUBS restrictions) and consult with your attorney or other qualified advisor to make sure your billing practices are compliant in your jurisdiction.

7. How SimpleSUB fits with how you already collect rent

SimpleSUB does not force you to change how you get paid.

You can keep using:

• Property management software
• Online payment tools
• Checks, Zelle, or whatever your current setup is

SimpleSUB handles:

• Metering
• Data collection
• Bill splitting

You simply add the water amount for each unit to whatever system you already use. It becomes another line item, not another platform you have to convince residents to adopt.

8. What you get with SimpleSUB, in concrete terms

For each metered unit, you get:

• An over-the-pipe meter that installs without cutting pipe
• Battery-powered hardware, so no electrical work at the install point
• Built-in cellular connectivity (no WiFi required)
• Daily water usage data stored in your online dashboard
• Tools to input your city water bill and split costs by actual usage
• Visibility into abnormal usage patterns and potential leaks
• Ongoing platform updates and support from a team that works with properties of all sizes

Pricing starts at $349 per device with a $6 dollar / month subscription. When you compare that to the cost of plumber time, wasted water, and manual billing overhead, the numbers become very compelling.

SimpleSUB is trusted on larger, more complex properties; for a duplex or quadplex, you get the same professional-grade system, scaled down to exactly the number of meters you need.

What does payback look like?

It is one thing to say “it pays for itself.” It is another to see how that actually plays out, whether you are already billing for water or not.

If you are currently passing water costs along

Even if you already bill residents for water, there is a limit to what feels fair.

If a leak runs for weeks behind a wall and your city bill suddenly jumps hundreds of dollars, most owners will not pass that full spike through to residents who had no way of knowing it was happening. In practice, you often split the difference, discount the bill, or simply eat the extra cost to avoid angry phone calls and lease issues.

Without submetering and real leak detection, you are exposed to:

• Higher total usage from leaks and overuse
• Large surprise bills that you feel obligated to absorb or discount
• Disputes because residents cannot see a clear connection between their behavior and the charges
  

With SimpleSUB in place, you can catch leaks early, show residents their actual usage, and bill from a position of clarity instead of guesswork. That reduces both the size of surprise bills and the likelihood that you are the one eating them.

If you are not currently passing water costs along

If water is “included” in rent, the payback math is actually very simple.

1. Pull your water bills for the past 12 months
2. Add them up
3. That total is what you could have passed through to residents if you had a fair, usage based system in place
   

Right now, that entire amount is coming out of your pocket. With SimpleSUB installed on your duplex, triplex, or quadplex, you have the foundation to:

• Measure each unit’s usage
• Allocate 100 percent of the water bill based on actual consumption
• Treat water like any other pass through utility instead of a mysterious line in your budget

Against that, you are weighing:

• Hardware starting around 349 dollars per device
• A 6 dollars per month subscription per meter.
  

In many cases, a single year of “water included” costs is more than enough to cover the one time hardware and the first year of subscriptions. After that, every month you are recovering money you were previously eating, with less arguing about what is fair and a clear system to point to when questions come up.

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And in both cases, there is one more piece of ROI that is easy to overlook: your time.
‍Any solution that depends on manual reads, custom spreadsheets, and constant back and forth with residents is quietly costing you hours every year. SimpleSUB is designed to give you that time back while tightening up the financial side.

Who SimpleSUB is the best choice for:

SimpleSUB is the best water submetering choice for people who:

• Own or manage duplexes, triplexes, quadplexes, or other multifamily properties
• Feel every dollar on the water bill
• Want water costs to be fair, but do not want to become full-time utility administrators
• Are comfortable with simple DIY work (or hiring a handyman) but do not want invasive plumbing projects

If you recognize yourself in that list, you are exactly the kind of operator SimpleSUB is designed to help, whether you run a single quadplex or a portfolio of multifamily and community properties.

(And yes, SimpleSUB works great for larger apartments, HOAs, and mobile home parks, not just for smaller buildings.)

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Other options for submetering (and why SimpleSUB is still easiest)

Even when SimpleSUB is the best overall fit, it is helpful to understand other paths you might be weighing.

Most owners and managers of small multifamily properties end up comparing three options:

1. SimpleSUB Water
2. WiFi-based over-the-pipe devices
3. Cheap in-line meters from Amazon

Here is how they stack up.

Option 1: SimpleSUB Water

See above for all the reasons we think SimpleSUB is the no-brainer option for submetering small to medium multifamily properties!

Option 2: WiFi-based over-the-pipe devices

These products clamp onto the outside of the pipe and send data to an app, usually over WiFi. They are often marketed as smart leak detectors or whole-home water monitors.

What they do well

• Non-invasive install (over the pipe)
• App-based usage data, sometimes with real-time flow
• Helpful for watching usage and spotting leaks, especially if you live on site

Where they fall short for duplexes, triplexes, and quads

1. Dependence on WiFi and power

Most of these devices assume:

• Strong WiFi coverage at the install location
• A nearby electrical outlet

That is fine in a single-family home where the owner lives there. At a small multifamily property, especially if you are off-site, it can be a major headache. If WiFi goes down or tenants change routers, your metering can break.

2. Limited billing support

These systems are primarily designed to show usage, not to split an actual city bill between multiple units.

You still have to:

• Take the usage numbers from their app
• Move them into a spreadsheet
• Decide how to handle fixed fees and sewer
• Communicate amounts owed
• Track who has paid

You get more visibility, but you still do all the billing work.

3. More devices, more complexity

One gadget in one home is easy enough. Multiple devices across a building, each needing WiFi, power, and configuration, can start to feel like you are running a small IT network.

Option 3: Cheap in-line meters from Amazon

These are the classic “I will just grab a few meters and figure it out” choice. They are typically mechanical in-line meters that you plumb into the water line.

What they offer

• Low upfront hardware cost
• Simple mechanical technology with no network dependencies

Where they fall short

1. Invasive installation

To install in-line meters, someone has to:

• Shut off water to the building
• Cut into existing pipes
• Add new fittings and connections
• Test for leaks

If you are not already experienced with plumbing, you will probably hire a professional. By the time you pay for labor and materials, the “cheap meter” may not be so cheap.

2. Manual reading and billing forever

These meters do not send data anywhere. Every billing period you must:

• Drive to the property
• Read each meter
• Write down or photograph the readings
• Subtract last month’s reading from this month’s
• Enter everything into a spreadsheet
• Split the water bill manually

You are committing yourself to this routine every month for as long as you own the property. That is time you could spend on higher-value work.

3. No built-in leak detection or patterns

You might spot a leak if you notice a huge jump in a meter’s reading, but there is no automated pattern recognition or alerting. You mostly find problems when the city bill is already high.

4. No billing engine at all

These meters only show totals. All allocation logic, communication, and tracking lives in your spreadsheet and your head.

Side-by-side comparison (with how it feels month to month)

Common concerns (and why they usually fade after install)

Even when the fit looks good, it is natural to have concerns. Most owners and managers ask some version of these questions.

“Is this overkill for just a few units?”

At a big complex, a few percent of waste or unfair allocation gets absorbed. At a duplex or quadplex, every dollar hits your pocket directly.

SimpleSUB is trusted on larger, more complex properties. The economics that make sense there are even more obvious at smaller buildings, where a single leak or heavy user can distort your entire bill.

“I am not very technical. Can I actually handle this?”

You do not have to be technical to use SimpleSUB.

The install is physical, not digital. Clamp the meter onto the pipe, tighten the zip ties, and follow a guided setup. From there, you mostly log in once a month to enter your bill and review numbers.

There is no WiFi configuration or networking to manage, and if you prefer, you can hire a handyman or plumber for the physical part of the install and handle the billing yourself.

“Couldn’t I just buy cheap meters and read them by hand?”

You could. Many people start there.

The real question is whether you want to commit yourself to:

• Showing up at the property every billing period
• Reading meters in basements or crawlspaces
• Maintaining your own billing spreadsheet for years

SimpleSUB is designed for the version of you six months from now, when the novelty has worn off and you just want water billing to be handled with as little effort as possible.

Ongoing support included!

SimpleSUB is used by owners and operators of duplexes, triplexes, and quadplexes; larger apartment communities; HOAs; and mobile home parks; to monitor and allocate water fairly across a wide range of properties.

Behind the hardware and software is a team that spends its time thinking about real-world plumbing layouts, billing questions, and how to keep things simple for people who cannot spend all day on this.

Support does not stop after installation. You can get help with:

• Choosing meter locations
• Understanding unusual usage patterns
• Fine-tuning your billing rules

You are not left on your own with a box of hardware and a PDF.

Quick FAQ

Do I need a plumber to install SimpleSUB

Most likely no. Many owners and managers install SimpleSUB themselves, since it clamps over existing pipe and uses zip ties rather than new fittings. If you prefer professional help, most plumbers or handymen can install quickly because there is no pipe cutting.

What if my plumbing layout is a little weird

Most small multifamily properties still have identifiable feeds for each unit (or at least for logical groupings of fixtures). If your layout is unusual, the SimpleSUB team can help you think through where meters should go to achieve fair billing.

Do my residents need an app

Nope! SimpleSUB is built for owners and managers. You log in, see usage and billing allocations, and then use your existing tools to communicate amounts owed and collect payment.

If you want to, you can set up tenant leak alerts via email and/or text, but that's optional!

What happens if a meter stops sending data

If a device ever stops reporting, you will see it in your dashboard and can work with support to troubleshoot. The system is designed so that you are not guessing in the dark.

What if I add more properties later

You can add more meters and buildings into the same SimpleSUB account. The same hardware and platform work for duplexes, larger apartments, HOAs, and community properties, so you do not have to switch systems as your portfolio grows.

Bringing it all together

If you manage a duplex, triplex, or quadplex, you do not want to become a full-time water manager. You want:

• Fair and transparent water costs between units
• Protection from surprise bills caused by leaks and overuse
• A simple monthly routine that you can stick with for years
• A system that is reasonably priced and easy to maintain

You could install cheap in-line meters and sign yourself up for manual reads and spreadsheets every month. You could set up WiFi-based gadgets that add visibility but still leave billing on your shoulders. You could try to force a large-scale billing provider to bend their process around your four-plex.

Or you can choose the option that is the best choice for both small multifamily buildings and larger properties.

SimpleSUB gives you:

• Over-the-pipe meters that install in minutes
• Battery power and cellular connectivity, so you are not chasing outlets or WiFi
• Daily usage data tuned for billing and leak detection
• Built-in tools to split your real water bill by actual usage
• A monthly process that looks like: log in, enter bill, review, done

Install once, and you can turn a messy, shared utility expense into a clean, repeatable system that works for your duplexes today and scales with you as your portfolio grows.

If you own or manage a duplex, triplex, or quadplex and you are tired of guessing at water costs, the next step is simple. Decide where you want meters installed, and explore how quickly SimpleSUB can pay for itself in reduced waste and cleaner billing, knowing you are using the same technology trusted by much larger properties.

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