It can be wherever you want, within reason, if you do a custom shower pan. Some shower pans are made to replace bathtubs so the drain is at one end. I am not sure you will find a prefab one to your exact specifications.

i know schluter has a kerdi shower kit that has the drain off-set like that... not sure of the exact dimensions, but i know it's possible as long as you keep the slope right on each side.

If you can't find a shower pan that meets your needs you can always build one it with concrete, just be sure that you have an even slope to where ever the drain ends up being.

Does it HAVE to be in the centre? No, I guess not. Should It BE in the Centre? In my world, YES, IT SHOULD.

One thing not yet mentionsed that you may want to consider:
If the drain is off center, like you are suggesting, remember that the pitch needs to occur over the length, which would result in one of two things- either the long side would progress upward higher than the short side, or the short side would need to be steep to match the other side.

If the drain is really at the edge, then just think about how it may feel to have it all falling off to the drain.

Perhaps if you can visit a showroom that sells a prefab one (whether or not you intend on using that or mud), you can get a sense of what that may look and feel like.

hope that made sense...

In our new build I got absolutely nuts about have things centered. DH finally pointed out that our old house had a rebuilt shower with an off center drain that I had not noticed in over 20 years of living there. So if you are worried about the "visuals" I think unless it is completely off in some way that even the nuttiest person (me, for example) wouldn't notice.

I know this is odd, but I love having the tub drain opposite the fill/faucet/showerhead because when cleaning, everything rinses in the correct direction. It happened by accident, as I wanted the water piped on the right with a panel door for easy access through the closet in the next room. It's a nice feeling, to have simple access for upgrades or repairs, and to check after earthquakes to know alls well.

We are planning on using a trench drain at one end of the shower. The entire floor will slope towards it. (the floor is not level already so we plan to exploit that).

Scupper drain? Please discribe.
I'm fascinated with the trough concept, seem functional in so many applications.
How are they installed and cleaned? Love the look but wonder about keeping clean and fresh?

Bodica I love the pictures you posted, even those outdoor drains are way cool. As for the floor drains I have done some research with this company quickdrainusa.com I don't have any permanent decisions yet.

Here is a link that might be useful: quick drain usa

jjaazzy thanks for the link to quick drain, do you know how they are to be cleaned? We all know how debris collects in a trap, with the outdoor troughs, I imagined they lift out to clean like a gutter, then I thought, what a job! I really love the decorative looks, but still question how difficult to keep clean of hair, spiders, etc. that just rinsing can not resolve?

A year ago I had asked schluter if they were going to do a trench drain. They can have a huge market if they make a drain and kerdi system for the trench look but i didnt hear anything definite from them. I should collect royalties for my suggestion :)

I think the clean linear look will be the next trend in shower design. The center drain is aesthetically unpleasing for a modern bathroom. With curbless showers becoming more popular, the trench is a natural fit.

Schluter, please listen and give us what we want ;) otherwise i will be forced to look at chinese knockoffs...

Pharaoh - I'm pretty sure that the kerdi system can be made to work with the quick drain system. Their competitor's membrane system is actually shown in the install pics. The bonding flange is is very similar.

Bill V. or Mongo may know definitively.

Pharaoh, I'm with you, with aging baby boomers, the need for easily accessable and cleanable designs should grow, and easy doesn't mean medical looking, just wisely designed to look fabulous AND function well for many needs. No curbs or tracks must be the way of the future and design for quick clean is long overdo.
kgsd, I think it will be fine for your drain to be where it is and enjoy the extra two feet of elbow room. Sorry for wandering off topic.

To the OP, kgsd:

Yes, drains can be offset form the center of the floor. It happens all the time, especially in larger walk-in showers.

A couple of considerations...with offset drains it's best to keep the bottom edge of the bottom course of wall tile at the same height all the way around the shower.

That means that the perimeter height of your sloped floor pan, where it meets the wall, will be the same elevation al around the shower.

Code requires a couple of things; that the minimum slope of the shower floor be at least 1/4" per foot, that the maximum slope be 1/2" per foot, and that the height of the curb needs to be 2" above the height of the drain.

If your drain is centered in the existing 36" square pan, you have 18" from drain to wall. Add 24" to one side for a 3' by 5' shower and you'll have distances of 18", 18", 18", and 42".

Using 1/4" slope per foot on the long run will give you a needed rise of 7/8".

Taking that 7/8" elevation and applying it to the three short runs will give you a slope slightly steeper than 1/2" per foot.

To fans of trough drains. They are easy to construct, I've done one "old school" and a couple using Kerdi. Made the troughs myself when setting the dry pack. I also made one out of copper, bent on a brake and soldered the corners.

Drain the floor to the trough, then drain the floor of the trough to the drain.

Factory trough drains are available, but expensive, since most every shower I've done is a one-off size, it's much easier to just make my own. Plus I know it'll work.

Check with your building department. The first one I did the inspector wanted me to tear it out. After I educated him, he allowed it.

Mongo the insomniac

Mongo,

When making your own trench drain, what did you use for a drain cover?