Why IRC Says Toilet 30" From Adjacent Fixture?

[Bird Doo Head]

Hi All!
For nearly all codes that I read, no matter the trade, it's relatively easy to figure out, or find out, the "why" behind the regulation. The one I've never been able to figure out is the reason that there has to be 30" from the center line of a toilet bowl and the nearest adjacent fixture. Example: C/L toilet to C/L of a vanity sink. The other toilet clearance rules all make sense, especially the ADA ones, but this one escapes me.

I've looked on line, asked plumbers and even 2 inspectors. No one knew. We're planning a bathroom and the rule popped back into my head.
I should have asked here years ago since you all will know.

Thanks For Helping me solve one of the many "think of it in the middle of the night" things that clutter my brain.
Paul.

 

[CT18]

You only need 15" from side of vanity. The 30" is for side to side toilets. It is actually more because of the partition, you need 15" clear from that side wall to center toilet. The partition is roughly an 1". Most gang toilet rooms they center them 36", like the ones i am drawing now.

 

[Bird Doo Head]

You only need 15" from side of vanity. The 30" is for side to side toilets. It is actually more because of the partition, you need 15" clear from that side wall to center toilet. The partition is roughly an 1". Most gang toilet rooms they center them 36", like the ones i am drawing now.

Hello CY18,

Thank You for replying & explaining. I appreciate your clarifying that the intent is toilet-to-toilet (if I understand your words correctly).

There are a whole lot of drawings on line & in How-To books showing 30" required C/L toilet to C/L vanity sink, This must be where the confusion originates (inspectors, too from those with whom I've spoken).
Personally, I appreciate having a sink within arm's reach of the toilet.

When I look at IRC, it is rather ambiguous & easy to get confused as you can see in the attached screen shot.

 

[havasu]

I read that as the toilet spacing to sit down should be at least 30" (15" off center to the left and right) and 21" in front of the toilet, so you don't smack your head while sitting down.

 

[CT18]

If you have a 30" vanity and you put the drain in the center and keep 15" clear from center of toilet then you will get 30" center to center of drain

 

[Bird Doo Head]

Thanks for the drawing CT18.
It's the lower drawing showing center line of toilet to the center line of the sink that I don't understand.

Suppose one has a pedestal sink or a wall-hung. The toilet center line can easily be within 30" of the sink's center line. Actually, in our house one of the bathrooms has a pedestal sink whose center line is less than 30" from the center line of the toilet.

I guess I don't understand why does the sink care if the toilet is close? (Assuming the 15" is maintained)

 

[havasu]

You guys just got me running to the bathrooms with a tape measure. I squeaked by on one toilet!

 

[TomFOhio]

I believe those measurements are for ADA and not regular bathroom. Of course the codes may have changed on me.