We just got a lovely new vinyl bathroom floor put in. The edges (wall, tub) are nicely caulked but not the base of the toilet.

I did read What kind of caulk to use in order to caulk the toilet to the floor? where everybody said "don't caulk," but I'm concerned because the toilet sits three feet away from a washing machine. The floor isn't perfectly horizontal. It slopes slightly down toward the toilet. The washing machine might leak, or someone might pull something wet out of the washer and drip water on the floor. Also, another three feet in a perpendicular direction and we are looking at a bathtub with shower curtain. More opportunities for spills. I don't want spilled water to get under the toilet. This was a problem previously with the washing machine I used to have (was just replaced a week ago).

At that linked question, I read that if you caulk, then you should leave a gap in the caulk around the base of the toilet. I guess I could pick a segment that is at a maximum distance from both the washer and the tub. Is a one inch gap enough?

Underneath the vinyl flooring (that was cut from a long roll at Home Depot) is plywood subflooring. Under that is a primitive cellar.

  • What is the floor made of?
    – Kris
    Apr 12, 2019 at 3:26
  • @kris - vinyl..... Apr 12, 2019 at 6:58
  • I’m sorry I meant what is the substrate. Is the vinyl on top of concrete or wood framed floor?
    – Kris
    Apr 12, 2019 at 12:27
  • familyhandyman.com/plumbing/….
    – Kris
    Apr 12, 2019 at 12:35
  • @kris I find the number 1 leak point for a toilet to be the wax ring. this leaks right onto the floor. So I disagree with that part of the article, you might want to sumirize the article because if the it moves or is taken down no one will have a clue what it said.
    – Ed Beal
    Apr 12, 2019 at 16:24

1 Answer 1


This is an argument that seems to never end. I work for several hotels and in every single room the toilet is caulked. It just plain looks nicer and it helps to stabilize the toilet. Some say that it will hide a leak but that makes limited sense. If a toilet leaks at the base, it's usually related to the flange leaking. Now, if the toilet gets cracked for some reason you might get a leak there but that's rare. Also, what if someone or an animal urinates and it gets underneath the base of the toilet? How would you clean that? Consider just water sitting under there and stagnating. I'm a big fan of caulking around a toilet. Although, you have to do it right. Use tape if you are inexperienced and don't buy anything cheap.

If you do choose to caulk, use a 100% silicone mold-resistant caulk like GE.

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  • 2
    I agree it looks better and help stabilize but several inches in the back should be left open especially if wood based sub flooring. I have repaired homes that were sealed well the leak went through the floor rotted it and the joists it ended up being a large repair that if they would left a few inches open in the back the leak would have been found and repaired instead of the wall, underlayment , decking and 2 joists. This was the worst one but I have done several that the underlayment was ruined.
    – Ed Beal
    Apr 12, 2019 at 16:18

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