# Why is the average bathtub not long enough for an adult to stretch out in? **URL:** \ **Category:** Factual Questions\ **Created:** [February 19, 2012, 9:15pm UTC](https://boards.straightdope.com/t/why-is-the-average-bathtub-not-long-enough-for-an-adult-to-stretch-out-in/613355 "2012-02-19T21:15:55Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![Tim\_T-Bonham.net](https://avatars.discourse-cdn.com/v4/letter/t/46a35a/32.png) [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)\ **Post date:** [February 19, 2012, 11:41pm UTC](https://boards.straightdope.com/t/why-is-the-average-bathtub-not-long-enough-for-an-adult-to-stretch-out-in/613355/21 "2012-02-19T23:41:29Z")
> [@aceplace57](#): > > Found this Vol calculator > I entered 6.5, 2.5, 1.5 and it says 182.08 gallons. times 8.35 = 1520 lbs. plus a 230 lb obese American male = 1750 lbs Thats a lot of weight concentrated in a small area of the floor. For a tub 30 inches wide and 6.5 ft long and only 18 inches of water. > > [http://www.dep.state.pa.us/dep/deputate/waterops/redesign/calculators/volcalchtm.htm](http://www.dep.state.pa.us/dep/deputate/waterops/redesign/calculators/volcalchtm.htm) You’re double-counting there. If you filled the tub that full, then that obese male would displace quite a bit of the water when he got in the tub, so you can’t count both. ---
**Author:** ![aceplace57](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/aceplace57/32/3500_2.png) [@aceplace57](https://boards.straightdope.com/u/aceplace57)\ **Post date:** [February 19, 2012, 11:44pm UTC](https://boards.straightdope.com/t/why-is-the-average-bathtub-not-long-enough-for-an-adult-to-stretch-out-in/613355/22 "2012-02-19T23:44:15Z")
Depth makes a big difference in how much water is needed. I was estimating a luxury bath with a 18 inch depth. The average home tub is more like yours and about 10 to 12 inches at most. t-bonham makes a valid point. I didn’t consider water displacement when someone gets in the tub. My mistake, glad someone caught it. ---
**Author:** ![CrazyCatLady](https://avatars.discourse-cdn.com/v4/letter/c/dfb087/32.png) [@CrazyCatLady](https://boards.straightdope.com/u/CrazyCatLady)\ **Post date:** [February 20, 2012, 12:06am UTC](https://boards.straightdope.com/t/why-is-the-average-bathtub-not-long-enough-for-an-adult-to-stretch-out-in/613355/23 "2012-02-20T00:06:21Z")
Because for the most part, people don’t want to take naps in there. By and large, most folks are either in a tub to get clean, which is more easily accomplished when you’re sitting up and can reach the soap, shampoo, etc, or to lounge with a book, glass of wine, etc, which is also easier sitting up. And, historically speaking, modern standard tubs are luxuriously large. Back when water had to be hauled and heated by hand, tubs were much smaller. ---
**Author:** ![Foggy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/foggy/32/1082_2.png) [@Foggy](https://boards.straightdope.com/u/Foggy)\ **Post date:** [February 20, 2012, 1:22am UTC](https://boards.straightdope.com/t/why-is-the-average-bathtub-not-long-enough-for-an-adult-to-stretch-out-in/613355/24 "2012-02-20T01:22:11Z")
> [@BrainGlutton](#): > > I don’t mind if they make it narrower, so long as they make it longer. There is a dick joke in there, but I’m not going to go after it.:p:D ---
**Author:** ![Senegoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/senegoid/32/6606_2.png) [@Senegoid](https://boards.straightdope.com/u/Senegoid)\ **Post date:** [February 20, 2012, 1:31am UTC](https://boards.straightdope.com/t/why-is-the-average-bathtub-not-long-enough-for-an-adult-to-stretch-out-in/613355/25 "2012-02-20T01:31:11Z")
I don’t take sit-down baths very often (that’s more of a girl-thing, n’est-ce pas?) but I’ll remark this of the times I did: Standard tubs are obnoxiously uncomfortable to sit in, even with water. Enough so that I’ll stick with stand-up showers. ---
**Author:** ![jz78817](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jz78817/32/1028_2.png) [@jz78817](https://boards.straightdope.com/u/jz78817)\ **Post date:** [February 20, 2012, 2:15am UTC](https://boards.straightdope.com/t/why-is-the-average-bathtub-not-long-enough-for-an-adult-to-stretch-out-in/613355/26 "2012-02-20T02:15:32Z")
> [@CrazyCatLady](#): > > Because for the most part, people don’t want to take naps in there. > > By and large, most folks are either in a tub to get clean, which is more easily accomplished when you’re sitting up and can reach the soap, shampoo, etc, or to lounge with a book, glass of wine, etc, which is also easier sitting up. And, historically speaking, modern standard tubs are luxuriously large. Back when water had to be hauled and heated by hand, tubs were much smaller. this is why I prefer the kind of tubs I encountered in Japan. They were even shorter than the “standard” american bathtub, but were significantly deeper. much easier to sit up with a comfortable level of submersion. ---
**Author:** ![tellyworth](https://avatars.discourse-cdn.com/v4/letter/t/977dab/32.png) [@tellyworth](https://boards.straightdope.com/u/tellyworth)\ **Post date:** [February 20, 2012, 2:28am UTC](https://boards.straightdope.com/t/why-is-the-average-bathtub-not-long-enough-for-an-adult-to-stretch-out-in/613355/27 "2012-02-20T02:28:01Z")
> [@aceplace57](#): > > Also, people were shorter a hundred years ago. I’ve seen museum exhibits of 19th century clothing and those people were typically much shorter. They’d almost fit in a 5ft tub. Not so. [Previous thread](http://boards.straightdope.com/sdmb/showthread.php?t=235399). People were a bit shorter in centuries past, but only an inch or two. ---
**Author:** ![tellyworth](https://avatars.discourse-cdn.com/v4/letter/t/977dab/32.png) [@tellyworth](https://boards.straightdope.com/u/tellyworth)\ **Post date:** [February 20, 2012, 2:29am UTC](https://boards.straightdope.com/t/why-is-the-average-bathtub-not-long-enough-for-an-adult-to-stretch-out-in/613355/28 "2012-02-20T02:29:14Z")
The average bath has to fit in the average bathroom. ---
**Author:** ![tomcar](https://avatars.discourse-cdn.com/v4/letter/t/7993a0/32.png) [@tomcar](https://boards.straightdope.com/u/tomcar)\ **Post date:** [February 20, 2012, 4:02am UTC](https://boards.straightdope.com/t/why-is-the-average-bathtub-not-long-enough-for-an-adult-to-stretch-out-in/613355/29 "2012-02-20T04:02:08Z")
I think small bathroom is the answer. I am 5’9" and never fit in bathtubs. I love a hot bath in the winter but they are generally uncomfortable affairs. ---
**Author:** ![clarkstar](https://avatars.discourse-cdn.com/v4/letter/c/439d5e/32.png) [@clarkstar](https://boards.straightdope.com/u/clarkstar)\ **Post date:** [February 20, 2012, 8:23am UTC](https://boards.straightdope.com/t/why-is-the-average-bathtub-not-long-enough-for-an-adult-to-stretch-out-in/613355/30 "2012-02-20T08:23:17Z")
> [@aceplace57](#): > > Weight on the floor could be a big issue. Water is incredibly heavy and a tub 6.5 feet long would require a lot of gallons. It would require extra framing and maybe even a support post or wall to carry it. > > I’ll let one of our math geniuses tell us how many gallons are in a 6.5 ft x 18 inches deep container. > > [How much does an Gallon of water weigh? - Answers](http://wiki.answers.com/Q/How_much_does_one_gallon_of_water_weigh) according to[this](http://www.build.com/american-standard-2774-018w-72-x-42-drop-in-whirlpool-tub-from-the-cadet-series/p1051628), a 72 42 tub only holds 82 gallons. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [February 20, 2012, 8:43am UTC](https://boards.straightdope.com/t/why-is-the-average-bathtub-not-long-enough-for-an-adult-to-stretch-out-in/613355/31 "2012-02-20T08:43:13Z")
> [@t-bonham@scc.net](#): > > You’re double-counting there. If you filled the tub that full, then that obese male would displace quite a bit of the water when he got in the tub, so you can’t count both. Only once he’s lying down and floating in the water. If you fill a bath full up to the brim, then step into it, the floor is bearing the weight of all the water, plus your body weight, minus the weight of water displaced by your feet and lower legs(not much). Sure, the weight will go down when you lie down and the water displaced by your body goes down the overflow, but the peak load may be higher than the weight of the filled bath. Maybe somewhat moot, because I doubt this happens very often. ---
**Author:** ![Shalmanese](https://avatars.discourse-cdn.com/v4/letter/s/45deac/32.png) [@Shalmanese](https://boards.straightdope.com/u/Shalmanese)\ **Post date:** [February 20, 2012, 9:26am UTC](https://boards.straightdope.com/t/why-is-the-average-bathtub-not-long-enough-for-an-adult-to-stretch-out-in/613355/32 "2012-02-20T09:26:48Z")
> [@aceplace57](#): > > Found this Vol calculator > I entered 6.5, 2.5, 1.5 and it says 182.08 gallons. times 8.35 = 1520 lbs. plus a 230 lb obese American male = 1750 lbs Thats a lot of weight concentrated in a small area of the floor. For a tub 30 inches wide and 6.5 ft long and only 18 inches of water. > > [http://www.dep.state.pa.us/dep/deputate/waterops/redesign/calculators/volcalchtm.htm](http://www.dep.state.pa.us/dep/deputate/waterops/redesign/calculators/volcalchtm.htm) IOW, it’s less than the weight of 8 people. Modern houses are obviously built to support more than 8 people standing in an area that large so that can’t be it. ---
**Author:** ![Dr.Colossus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.colossus/32/9423_2.png) [@Dr.Colossus](https://boards.straightdope.com/u/Dr.Colossus)\ **Post date:** [February 20, 2012, 9:57am UTC](https://boards.straightdope.com/t/why-is-the-average-bathtub-not-long-enough-for-an-adult-to-stretch-out-in/613355/33 "2012-02-20T09:57:26Z")
about the weight: old clawfoot tubs, as mr. fluff pointed out, are already heavier and were larger–and they concentrated all their weight on 4 localized points–not evening distributing it across the whole bottom. not to mention old flooring didn’t usually have plywood or sheet underlaying–it was thin tongue and groove oak or pine, lain directly on the joists–and the slats weree usually just a few inches wide. there’s a LOT of exacerbating symptoms for a fall-through, is what i’m saying, and i never heard of it happening, so it was at the very least infrequent. ---
**Author:** ![flodnak](https://avatars.discourse-cdn.com/v4/letter/f/838e76/32.png) [@flodnak](https://boards.straightdope.com/u/flodnak)\ **Post date:** [February 20, 2012, 9:59am UTC](https://boards.straightdope.com/t/why-is-the-average-bathtub-not-long-enough-for-an-adult-to-stretch-out-in/613355/34 "2012-02-20T09:59:13Z")
Another vote for small bathrooms. Ever seen the bathrooms in houses from when indoor plumbing was first becoming common? A five-foot/one-and-a-half meter tub still takes up as much as half of the space. And most families wouldn’t have used the tub every day at that time. When a house does have a larger bathroom, many people are now opting for a separate shower stall. That’s what we chose when we had our bathroom enlarged. With no little kids in the house any more, we use the tub only a few times a month, but the shower is in heavy daily use. When you’ve set aside the space for the shower stall, you need a bathroom large enough to hold square dances in to still have the space for a tub a tall adult can lie down in. The market is probably still too small for most manufacturers to bother with extra long tubs, and too small for most bathroom supply stores to stock any that _are_ out there. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [February 20, 2012, 10:18am UTC](https://boards.straightdope.com/t/why-is-the-average-bathtub-not-long-enough-for-an-adult-to-stretch-out-in/613355/35 "2012-02-20T10:18:54Z")
Modern plumbed-in baths evolved from the older claw-foot type (with or without hot running water), which in turn evolved from a tin tub in front of the hearth, with water warmed in metal jugs or pans and poured in. Throughout the course of that evolution, there’s a general increase in size, but it’s probably never been hugely desirable to have a full-length bath - because bathing hasn’t ever really been about stretching out at full length and just lying there - it’s about scubbing, soaping, then immersing various bits of the body in turn in order to get clean. ---
**Author:** ![chappachula](https://avatars.discourse-cdn.com/v4/letter/c/d2c977/32.png) [@chappachula](https://boards.straightdope.com/u/chappachula)\ **Post date:** [February 20, 2012, 12:20pm UTC](https://boards.straightdope.com/t/why-is-the-average-bathtub-not-long-enough-for-an-adult-to-stretch-out-in/613355/36 "2012-02-20T12:20:54Z")
> [@t-bonham@scc.net](#): > > . If you filled the tub that full, then that obese male would displace quite a bit of the water when he got in the tub, EUREKA!!! (sorry…But somebody had to say it.) ---
**Author:** ![kayaker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kayaker/32/441_2.png) [@kayaker](https://boards.straightdope.com/u/kayaker)\ **Post date:** [February 20, 2012, 12:46pm UTC](https://boards.straightdope.com/t/why-is-the-average-bathtub-not-long-enough-for-an-adult-to-stretch-out-in/613355/37 "2012-02-20T12:46:13Z")
I’d like an upright tub design. Imagine a shower stall with a solid door that is about three feet high. You would have a swimming pool type ladder on the door, climb in and sit. With around the same volume of water as a typical bathtub, you could sit fully submerged. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [February 20, 2012, 1:31pm UTC](https://boards.straightdope.com/t/why-is-the-average-bathtub-not-long-enough-for-an-adult-to-stretch-out-in/613355/38 "2012-02-20T13:31:44Z")
> [@kayaker](#): > > I’d like an upright tub design. Imagine a shower stall with a solid door that is about three feet high. You would have a swimming pool type ladder on the door, climb in and sit. With around the same volume of water as a typical bathtub, you could sit fully submerged. They exist - google _upright bathtub_ or\* soaking bathtub \* - looks like there are two kinds - those that you climb into from the top, and those that have a door in the side (obviously can only be opened when the tub is empty) - the latter sort being primarily marketed to disabled people who either can’t step into a bath, or can’t safely lie down in one. ETA: I imagine they probably use a fair bit more water than a conventional bath - by a factor of two or more, just because people wouldn’t want to be confined to a narrow vertical water-filled tube. ---
**Author:** ![BrainGlutton](https://avatars.discourse-cdn.com/v4/letter/b/82dd89/32.png) [@BrainGlutton](https://boards.straightdope.com/u/BrainGlutton)\ **Post date:** [February 20, 2012, 1:41pm UTC](https://boards.straightdope.com/t/why-is-the-average-bathtub-not-long-enough-for-an-adult-to-stretch-out-in/613355/39 "2012-02-20T13:41:35Z")
> [@KneeSid](#): > > Too soon for Whitney Houston jokes??? Did she even die in a bathtub? ---
**Author:** ![enipla](https://avatars.discourse-cdn.com/v4/letter/e/54ee81/32.png) [@enipla](https://boards.straightdope.com/u/enipla)\ **Post date:** [February 20, 2012, 2:13pm UTC](https://boards.straightdope.com/t/why-is-the-average-bathtub-not-long-enough-for-an-adult-to-stretch-out-in/613355/40 "2012-02-20T14:13:38Z")
> [@chacoguy](#): > > It can’t be weight, cause, ya know, waterbeds. That’s the first thing I thought of too. It’s not weight. It’s just the available room. I just did a huge remodel completely redoing the main bath and kitchen. I bought a 5.5 foot tub that is extra deep. The extra depth and extra 6 inches helps a lot. [Previous page](https://boards.straightdope.com/t/why-is-the-average-bathtub-not-long-enough-for-an-adult-to-stretch-out-in/613355.md?page=1) [Next page](https://boards.straightdope.com/t/why-is-the-average-bathtub-not-long-enough-for-an-adult-to-stretch-out-in/613355.md?page=3)