How to measure a toilet rough-in without removing it
Figuring out if a 10-inch or 12-inch toilet will fit is difficult when your current unit lacks visible floor anchor bolts. You cannot simply pull the toilet out to check if you only have one bathroom and need the replacement installed the same day. This leaves you unable to safely buy the new toilet before taking the old one out.
What the numbers show
Counted from the threads quoted below. How we count
- People have been saying this in most months since September 2026.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
Found another way around this?
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- 1Looking inside the tank or under the lid for model numbers and specification labelsDid this help you?
- 2Searching for old installation paperwork or looking up manufacturer spec sheets onlineDid this help you?
- 3Measuring to the center of the floor flange after pulling the toiletDid this help you?
- 4cheating the toilet forward a quarter inchDid this help you?
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“Problem is that I don’t seem to have a conventional toilet since there are no bolts to anchor it to the floor.”source ↗
“The thing is I only have one bathroom, so if I pull it out and don’t have a replacement kind of ready to be installed within the day, it’ll be a hassle. That’s why I wanted to buy the new toilet before removing the old one.”source ↗
“Will a 12 inch fit here or a 10 inch?”source ↗
Where this came up
People with this problem also raised
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- 7How to figure out correct plumbing and venting requirements for a remodel
- 3How to figure out what toilet seat shape I have