Greywater & Rainwater System Sizing Calculator
Use our free sizing calculator to estimate the water recycling potential for your commercial building. Designed specifically for M&E consultants, architects, and developers, this tool provides rapid volume estimates for greywater yield, rainwater catchment, and attenuation requirements.
System Size & Savings Calculator
⚠️ Retrofit Feasibility Notice
Rainwater harvesting and greywater recycling systems typically require a dedicated non-potable distribution network. In retrofit applications, installing separate pipework to serve WCs, irrigation, and other non-potable uses can be significantly disruptive and cost prohibitive, unless a wider plumbing refurbishment is already planned.
Greywater systems also require separate drainage collection from suitable sources (e.g. wash hand basins, showers and baths). Existing buildings are rarely configured for this, and modifications to drainage infrastructure can further impact feasibility.
We recommend early-stage review of distribution and drainage constraints before progressing to detailed design.
1. Building Details
2. Surfaces (Catchment)
3. Location & Climate
4. Storm Water Maximum Outflow Rate
5. Financials
Advanced Parameters
Results
Total Non Potable Demand
🚿 Greywater System
🌧️ Rainwater Harvesting
⚡ Stormwater Attenuation
💰 Potential Savings
Estimated 24-Hour Non Potable Profile (Peak Day)
Visual representation of greywater supply vs combined non-potable demand on a day where all systems (including irrigation) are active.
10-Year Estimated Savings Forecast
Projected financial returns assuming a standard 4% annual increase in water utility costs.
📩 Request a Detailed Quote
Send your system calculations directly to our engineering team.
