Sub-metering is a powerful solution for fair water usage billing and efficient water management in multi-unit properties. This guide covers:
- What is sub-metering and why it matters.
- Background and evolution of sub-metering.
- Key benefits for landlords, managers, and tenants.
- Modern sub-meter reading technologies.
- Best practices for successful implementation.
- A practical case study.
What is Sub-Metering?
Traditionally, water utilities supply a single water meter for a commercial or residential condo property, often located in an underground chamber at the property entrance. Utilities prefer this setup as it simplifies billing, sending one bill to the property management company and minimizing operational costs.
Sub-metering changes this by installing separate water meters in individual units within multi-unit residential or commercial properties. Each tenant or unit owner receives an accurate water usage reading instead of relying on a single, shared main water meter.
Background: Evolution of Sub-Metering
Water often receives less attention compared to gas and electricity because it’s generally cheaper. Historically, total water consumption was divided equally among tenants, which worked when usage was similar. However, this method doesn’t hold up when businesses in a building have vastly different water needs. For example, a restaurant’s water usage is significantly higher than that of an accounting office.
Thankfully, advancements in water meter technology have solved these inefficiencies. Modern meters can now detect flows as low as 1 litre per minute and eliminate the need for manual readings by enabling remote access.
Benefits of Sub-Metering
For Property Managers & Landlords:
- Accurate Billing: Bill tenants based on actual water usage.
- Remote Readings: Modern meters allow for remote data collection, saving time and labor costs.
- Water Loss Management: Identify leaks or losses by comparing the main meter reading with total sub-metered usage.
- Cost Management: Avoid unnecessary maintenance fee increases caused by inaccurate billing.
For Unit Owners & Tenants:
- Fair Billing: Pay only for your actual usage.
- Water Efficiency: Encourages conservation and reduces waste.
- Cost Savings: Avoid subsidizing high water users in shared billing setups.
Considerations:
While sub-metering has clear benefits, it does come with some costs:
- Installation Costs: Vary based on the chosen technology and infrastructure.
- Ongoing Maintenance: Includes meter servicing, billing administration, and troubleshooting high bills.
- Temporary Disruption: Installations require water shut-off for about 30 minutes per unit.
Reading Technology & Sub-Metering
Wired reading technology for commercial sub-metering is labour intensive, costly, and prone to tampering. The water meter industry has come a long way since the days of collecting water meter readings via pen and paper. RF water meter transmitters has revolutionized the water meter reading industry. Reading can be achieved either by the close proximity of the parking lot using unlicensed 910-920MHz technology or off-site data collection using cellular transmitting capabilities.
The newest sub-meter and reading technology incorporates features such as leak detection, no-flow detection and reverse flow detection. Additionally, these systems can data-log consumption hourly making it easy for property management to troubleshoot abnormal consumption based on the business type.
Best Practices for Successful Sub-Metering Projects
A good sub-metering project foundation starts with water meter selection. There are many choices when searching the internet for meters that measure or monitor your water usage especially in this day and age of iOT. Many times, these devices operate inferentially, meaning they don’t directly measure the flow and consumption. You will come across many different species of water meters including “clamp-on” and “insertion” type meters as you browse the web.
Our recommendation is to use what public water utilities throughout North America have been using for over a hundred years now to accomplish accurate water meter recording and timely reading and billing.
The two main types of water meters used by utilities today are either positive displacement or ultrasonic metering technology. Both are designed with a 20-year lifespan. Positive displacement meter accuracy will decline by 3-5% over it’s life whereas the ultrasonic holds its near perfect factory accuracy over its lifetime. The trade-off comes down to budget considerations as the newer ultrasonic technology is significantly higher in cost. The water meters will comprise a good chunk of your budget.
Another significant contributor to your budget will be determined by your reading system selection. As a general rule a system that requires the fewest reads/bills per year and also requires you to be at the property to collect the reading is often the lowest overall cost. This is typically a touchpad meter reading system that requires the reader to come to the property and probe every unit touchpad to obtain the reading. Conversely, obtaining cellular readings remotely offsite of the property will naturally be the highest overall project cost. The project cost will vary in between these two extremes based on reading interval requirements and the final selection of transmitter technology.
Water meter installations require the use certified water meter installer (5/8”-1” service size) or licensed plumber (all service sizes). Many authorized water meter distributors such as ESL have service groups that can help manage your overall project including unit owner communication, install scheduling as well as installation of the meters and reading system. Authorized distributors have in depth knowledge of the product and years of system integration experience minimizing any finger pointing should any bumps in the road are encountered.
Unlike residential homes whereby the water service almost always enters the basement from the front of the property, each commercial property is different and each unit within a property can
be unique in the way that the water service runs. If uncertain about the best approach, contact an industry professional for a consultation. Generally, consultations are low in cost (if any) and negligible in comparison to the project cost. It will help you to determine the best overall fit for your requirements.
Practical Case Study
Evans Supply Limited helped Commercia’s retail/office condo property sub-meter in order to reconcile their tenant usage to their municipal water bill and at the same time created fair and equitable billing for this 31-unit ground floor condo strip mall. Tenant business profiles ranged from a food market to a bookstore. Add to that a travel agency, a dentist as well as several hair salons, massage therapy clinics and restaurants. Some units like the hair salons and restaurant did not have a sub-meter set up so the buildings water bill from the city was split amongst the tenants. This meant that the hair salon, which used more water, was getting a much better rate then the bookstore which hardly used any. Installing sub-meters in each tenant’s unit allowed for accurate and fair billing when it came time to paying their water bills. Read more about how sub-meters saved some tenants money and helped property managers mitigate water loss in this buildings case study.
Get Started Today
For fair and equitable billing amongst unit owners within your condo corporation as well as headache free reading and billing management, get in contact with us today.
