1-1/2" PVC, ABS, steel and no-hub cast iron pipe are 1.900" (48.3 mm) across the outside (cast iron 1.90"). 1-1/2" copper, PEX and CTS CPVC are 1.625" (1-5/8").
1-1/2 inch pipe sizes by type
| Pipe | Outside (OD) | Inside (ID) | Wall |
|---|---|---|---|
| PVC Schedule 40 or DWV | 1.900" (48.3 mm) | n/a | 0.145" |
| PVC Schedule 80 | 1.900" (48.3 mm) | n/a | 0.200" |
| CPVC Schedule 80 (Charlotte Corzan) | 1.900" (48.3 mm) | n/a | 0.200" |
| PVC or ABS foam core drain pipe | 1.900" (48.3 mm) | n/a | 0.145" |
| Steel Schedule 40, black or galvanized | 1.900" (48.3 mm) | 1.610" | 0.145" |
| Steel Schedule 80 | 1.900" (48.3 mm) | 1.500" | 0.200" |
| Cast iron, no-hub | 1.90" (48.3 mm) | 1.50" | 0.16" |
| Copper Type K | 1.625" (41.3 mm) | 1.481" | 0.072" |
| Copper Type L | 1.625" (41.3 mm) | 1.505" | 0.060" |
| Copper Type M | 1.625" (41.3 mm) | 1.527" | 0.049" |
| Copper DWV (drain) | 1.625" (41.3 mm) | 1.541" | 0.042" |
| PEX (Uponor AquaPEX) | 1.625" (41.3 mm) | 1.244" | n/a |
| CTS CPVC (FlowGuard Gold) | 1.625" (41.3 mm) | n/a | 0.148" |
PVC, ABS and CPVC: Charlotte Pipe’s average OD and minimum wall; its Corzan Schedule 80 CPVC is iron pipe size. Copper: the Copper Development Association’s nominal sizes. Steel: Wheatland Tube’s table. PEX: Uponor AquaPEX, whose table gives OD and ID. A cell marked n/a isn’t in the maker’s table. Cast iron: Charlotte Pipe’s barrel size and nominal wall. A no-hub pipe’s spigot end has a bead 1.96" across.
Charlotte Pipe makes one solid-wall 1-1/2" Schedule 40 PVC for both pressure and drain work, printed with both ASTM D1785 and ASTM D2665, plus foam core PVC and ABS drain pipe with the same outside. Its foam core pipe is for drainage only. Charlotte Pipe’s table of service weight hub and spigot cast iron starts at 2".
What fits a 1-1/2 inch pipe
- Sink traps: Oatey’s 1-1/2" tubular traps fit 1-1/2" O.D. drain pipe, which is 0.4" narrower than 1-1/2" Schedule 40. Oatey’s trap adapter fits 1-1/2" Schedule 40 PVC, so the trap can meet the pipe in the wall. See P-trap size.
- Copper, PEX and CTS CPVC: SharkBite sizes its 1-1/2" push-to-connect fittings 1-1/2" CTS, for pipe 1-5/8" across, and they take copper, CTS CPVC and PEX.
- PEX clamps and hangers: for its PEX, Uponor says to use copper tube size supports and clamps whenever possible.
- No-hub cast iron: it joins with hubless couplings (CISPI 310), and Charlotte Pipe doesn’t recommend or warrant its no-hub pipe joined with unshielded ones.
Measuring your pipe
Measure across an open end, or wrap a tape around the pipe and divide by 3.14. 1-1/2" Schedule 40 PVC is about 5.97" around, 1-1/2" copper about 5.11", and a 1-1/2" O.D. tubular part about 4.71". To tell the kinds of pipe apart, see what pipe do I have?