Why are marine toilet bowls so small?

Jan 11, 2014
Sabre 362 113 Fair Haven, NY
The topic heading says it all. There must be a reason for marine toilets to have such a small bowl. Anybody have an idea?
Feb 20, 2011
Island Packet 35 Tucson, AZ/San Carlos, MX
The smaller the boat you can fit one in, the more toilets you might sell.
Dec 2, 1997
- - LIttle Rock
Head compartments on most recreational boats used to be quite small before "cabin" boats became floating condos...and still are on smaller boats. The discharge hole in a marine toilet bowl is always in the center of the bowl, making the front-back measurement of larger household bowl longer in front and in back...the toilet has to sit further from the wall behind it, which makes space in front of the toilet a lot tighter...sometimes TOO tight to give knees enough room, and sometimes makes it impossible to close a head door that opens inward. So compact marine toilets--which is what almost all production sailboat builders use--always have what the industry calls "marine" bowls. The good news is, if you have the space for a larger household bowl, new toilets now offer a choice of a "marine" or "household" bowl or you can just swap out the "marine" bowl on an existing toilet for one...Doesn't have to be the same make/model toilet...Any bowl that has a 4-bolt mounting pattern will fit any other toilet that has the same mounting pattern.

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Jan 11, 2014
Sabre 362 113 Fair Haven, NY
Thanks Peggie. That's what I thought. Last year I did swap out the bowl. lt was an expensive but welcome improvement.


Jun 3, 2012
Hunter 33 Steamboat Wharf, Hull, MA
I originally had the Jabsco manual compact toilet. I compared the dimensions of their compact model to their "household size" model. Every dimension is only slightly larger for the household model. I was able to replace the compact with the household size which is much more comfortable. Most boats could probably make this change.
Oct 22, 2014
CAL 35 Cruiser moored EVERETT WA

You know the little 3 marks you find on top of a coconut.

Monkeys during the full moon climb into the trees. They find the young, soft, tenderest, coconuts to service. 3 times is the charm....

When I heard that explained in the islands, I never looked the same at coconut water, again.