Will a standard P-trap fit with a 5" vertical clearance?
A tight 5-inch vertical gap between the wall drain and a tall vanity or vessel sink leaves very little margin for error, with the P-trap requiring about 1 to 1.25 inches above the cabinet floor and 1.5 inches below the tailpiece. Homeowners struggle to figure out if this setup works without opening the wall and moving the plumbing down, while still leaving enough space below the bend to remove the trap for cleaning.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
- 1Opening the wall to lower the drain height
- 2Checking if the tight vertical clearance is sufficient for standard fittings
- 3Opening the wall to move the plumbing and add bracing
- 4Cutting the back panel or shelf of the vanity cabinet
- 5Lowering the desanco to create more space
- 6Calling in a plumber to configure the pipes
- 7Adding pipe to make the drain reach the new sink
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“Would 5" of vertical difference be enough to install a standard P-trap without lowering the drain inside the wall?”source ↗
“I’m trying to avoid opening the wall and moving the plumbing if possible.”source ↗
“Mine is a freestanding vanity with legs, so I’m mainly trying to figure out whether the 30" wall drain can work with a 35" vanity top and vessel sink without moving the drain.”source ↗
“The center of the existing wall drain is about 30" from the floor, so there is only about 5" between the wall drain and the vanity top.”source ↗
“Would 5" of vertical difference be enough to install a standard P-trap without lowering the drain inside the wall?”source ↗
“I’m trying to avoid opening the wall and moving the plumbing if possible.”source ↗
“Trying to DIY a floating bathroom vanity and I’m concerned about the limited clearance underneath the sink.”source ↗
“The bottom of the P-trap sits about 1–1.25” above the bottom of the cabinet. The top of the P-trap is about 1.5” below the bottom of the bare sink drain/tailpiece connection.”source ↗
“Wouldn’t lowering it also make the ptrap sit lower? There’s not much clearance in the cabinet as I also need space below the bend to remove the ptrap for cleaning.”source ↗
Where this came up
People with this problem also raised
- 7No room to fit a plumbing vent in tight spaces
- 4How to fit water supply lines in a tight bathroom vanity
- 2How to add a vent when you can't reach the stack
- 3How to fix a sink drain pipe that is too short
- 2How to route a plumbing vent offset around obstacles
- 3How to keep a drain hose from popping out of a PVC pipe