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PVC DWV fitting allowances
How far it is from where a fitting's center lines cross to the bottom of its socket, for PVC DWV 45° (1/8 bend) and 22 1/2° (1/16 bend) fittings, 1 1/2″ to 4″. Subtract it at each end of a piece to get the pipe to cut.
These are one maker's published figures; fittings vary, so check yours. The pipe offset calculator fills them in for you.
Verify with your local code and AHJ. Reference only, no warranty.
Center to socket bottom, each end
| 45° | 22 1/2° | |
|---|---|---|
| 1 1/2″ | 1 1/8″ | 1/2″ |
| 2″ | 1 1/2″ | 11/16″ |
| 3″ | 1 3/4″ | 13/16″ |
| 4″ | 2 3/16″ | 1″ |
Spears published center-to-socket — fittings vary, check yours.
Open the Pipe Offset calculatorOpen this sheet in the toolkit to search it, pin it and use it offline.
Questions
What is the fitting allowance for a 2 inch 45?
About 1 1/2″ for PVC DWV, each end. Check your fittings.
What is the take-off for a 3 inch 45?
About 1 3/4″ at each end for a PVC DWV 45. Check your fittings.
How do I use the allowance?
Measure center to center, then subtract the allowance of the fitting at each end. That is the pipe to cut.