Shower pan installation

I am in the middle of a remodel of the master bath. I have a Kohler shower receptor (pan) that is ready for installation. I have relocated the drain, trap (ABS). The trap aligns well with the pan (not glued up yet). The Kohler install instructions say nothing of laying a mortar bed under the pan is this a necessity? Is thinset mortar OK for this purpose, and how large should the mortar bed be? Also, the brass fitting in the pan has been installed using silicone under the flange, the rubber seal and then the fiber seal on the underside all tightened up. Does this sound correct? This is a second floor bath with no access from below.

Some pans don't require anything under them.

If the pan is flat on the floor, it's fine.
If there are gaps under the pan, you can use a filler to fill the void.
We mainly use fillers under deck installed tubs, these are hanging in space from the edges over space. Filling the space there makes them solid and supports the tub from the bottom.

Thanks, Terry
I just checked with Kohler to be sure. They claim that a mortar bed is not required on the smaller shower pans.(34X48) Just make sure its level and lay 30# felt on the subfloor before installing to reduce any squeeking.

It's not so much a required thing as a desirable thing. If you can, place the pan on a clean flat surface prior to installing it. Take your socks and shoes off. Walk on the the top of the thing. If you can feel it deflect/flex at all, you'll be happier if you fill in the voids under it to make it solid. If you can't feel anything move/flex, then don't bother with trying to impove it. The warranty should be the same either way - if the manufacturer says it is not needed.

Plumbers often use both teflon tape AND pipe dope on a threaded connection; either one should do the job on its own, but both usually means an absolutely bulletproof connection.

If you did do this, you'd use a sand/cement mix; not thinset.

A pro can give the the specific details if you decide you want to go this route, or check over at www.johnbridge.com for some useful reading on tiling.

Thanks for the guidance. I took off my shoes and just like you said ....the movement feels lousy. Sounds like cement and sand and a touch of lime and lay it down set the pan and be done with it.
Thanks
Pete

Hi, I have an issue with a Kohler receptor 9496. Something along the same lines as this post. This is a basin that extends up 21" along the walls. The instructions say that this unit needs to be supported by the floor of the pan- not the walls; and that the receptor sits plumb and level (that is if the floor existing is plumb and level). Simple enough, right? No. I get the product from Kohler, open the box and sit it on my plumb and level living room floor. The pan sits anything but. The bottom finish step (the one the track sits on for the shower doors) hits the floor 1st by maybe 1/2 to 1 inch and causes the whole thing to slant. I can't understand this??!! Kohler's instructions are clear that the pan sits flush and level on floor! It's the weekend and have to wait til Monday for Kohler. I know about the mortar thing (I did it on my whirlpool), but I didn't want to have to-- shouldn't have to, just #30 felt only. WTF??!! Anybody with similar issues with this pan?
--Chris

I use Strectolite to stabilize and level all molded pans. I don't know if it meets code in other parts of the US.