I’m sure I’m not the only home inspector who sees this on a regular basis, and it’s an issue I’ve wanted to address for some time. I’ve performed many home inspections after a bathroom remodel, and have seen these issues again and again – incorrectly sized toilets or incorrect clearances around and in front of a toilet. These issues are correct in the original bathroom, but for some reason, change during a remodel. It’s important that the proper building standards for toilet sizes / clearances are met when remodeling.
Toilet Rough-in Size
The rough-in size of a toilet is the distance between the center of the toilet flange (or the bolts mounting the toilet to the floor) and the wall. There are three rough-in sizes for toilets – 10”, 12”, and 14”. When replacing a toilet, it is important to measure the distance between the wall and the flange. This measurement may be off by ¼” to ½” or so, which is fine. It just means there will be a small space between the toilet tank and the wall. When people aren’t aware of the different toilet rough-in sizes, we see large gaps between the toilet tank and the wall. For instance, if you install a 10” toilet in a bathroom that was roughed-in for a 12” toilet, there will be a 2” to 3” gap between the toilet tank and the wall; a 10” toilet in where a 14” toilet should be will result in a 4” + gap between the toilet tank and wall.
The clearance on the sides of a toilet should measure a minimum of 15” from the wall (or cabinet, tub, shower…etc) to the center of the toilet, which equals a minimum of 30″ total area for the toilet from left to right. Some may think a few inches less is no big deal, but these standards have been in place a long time, and we’ve grown accustomed to them. So when you sit on a toilet that has less than 15” on either side, you feel it. If I find this during a home inspection, I will often put the toilet seat down, and have my client sit on the toilet (with their clothes on!) to feel the encroachment. “Wow” is their usual reaction. Yes, you really can feel it.
The standards for the clearance in front of a toilet do differ depending on the region of the U.S. you live in. Some standards require a minimum of 21” (as is the case in Phoenix, AZ); some require a minimum of 24”. I like to see at least 24”, but more is always better. Many plumbing fixture companies recommend at least 30”.
Hopefully this has shed some light on the issue of toilet clearances and sizing, and / or cleared up any confusion.