Grease Interceptor Size Estimator
Who it's for: Plumbing designers, commercial kitchen contractors, estimators, and facility teams.
Calculator Inputs
Quick Summary
- Built for: Plumbing designers, commercial kitchen contractors, estimators, and facility teams.
- Key outputs: Recommended interceptor gallons, Suggested standard size, and more.
- Use this page for early planning estimates before final code and manufacturer verification.
Inputs
- Kitchen type (light/medium/heavy)
- Fixture flow and retention time
- Sizing method (flow x time or fixture-based)
- Sink dimensions and fill percent (fixture mode)
Outputs
- Recommended interceptor gallons
- Suggested standard size
- Method used summary
- Local verification warning
How this calculator estimates results
- Supports a flow-times-retention method and a fixture-volume method for quick planning comparisons.
- Applies kitchen load factor assumptions (light, medium, heavy) to adjust base volume.
- Maps estimated gallons to the nearest common standard interceptor size.
Cross-check assumptions with Fixture Flow Rate Calculator for a more complete planning workflow.
Common ranges and tips
- Use consistent flow assumptions across related plumbing calculators to compare options cleanly.
- Heavy-load kitchens can drive materially larger interceptor estimates than light-duty spaces.
- Fixture-based mode is useful when sink geometry is known but peak flow is uncertain.
- Final sizing must be verified with local requirements and manufacturer guidance.
Related Calculators
FAQ
Start with flow x retention for a quick estimate, then compare with fixture-based mode when sink geometry is available.
Kitchen type applies a factor to estimated volume so heavier grease loads produce larger recommended sizes.
No. This is a planning estimator only and local codes and authorities may require specific sizing procedures.
Manufacturers may use different assumptions, performance criteria, and approved sizing methods than this MVP estimator.
Disclaimer: Use results for planning only. Final design and installation decisions must follow local code and manufacturer documentation.
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