1. Identify Total Installed Cost
This includes:
- Equipment cost
- Installation labor
- Any minor plumbing modifications
Example:
Total installed cost = $25,000
.
2. Calculate Monthly Water & Sewer Savings
Estimate savings based on:
- Historical water bills
- Property size and occupancy
- Typical savings range (often expressed as a percentage reduction)
Example:
Current monthly water/sewer cost = $10,000
Estimated savings = 15%
Monthly savings:
$10,000 × 15% = $1,500/month
.
3. Determine Annual Savings
$1,500 × 12 = $18,000 per year
.
4. Calculate Payback Period
This shows how quickly the system pays for itself:
Payback Period = Installed Cost ÷ Annual Savings
Example:
$25,000 ÷ $18,000 = 1.39 years
Payback ≈ 16–17 months
.
5. Calculate ROI Percentage
ROI expresses total return relative to cost:
ROI (%) = (Annual Savings ÷ Installed Cost) × 100
Example:
($18,000 ÷ $25,000) × 100 = 72% annual ROI
.
Long-Term Financial Impact
After payback, savings continue year after year:
| Year |
Cumulative Savings |
| Year 1 |
$18,000 |
| Year 2 |
$36,000 |
| Year 5 |
$90,000 |
| Year 10 |
$180,000 |
.
Additional Value Considerations
Beyond direct ROI, clients often see:
- Increased Net Operating Income (NOI)
- Higher property valuation (especially in multifamily/commercial real estate)
- Reduced strain on plumbing infrastructure
- Budget predictability with lower utility volatility
Simple Rule of Thumb
Most projects fall into this general range:
- Payback: 12–24 months
- Annual ROI: 50%–100%+
- Lifespan savings: 5–10× initial investment
Summary
The water bill savings valve is not just a conservation tool—it’s a financial performance upgrade:
- Fast payback
- Strong recurring returns
- No behavior change required