Solidifying shower floor??

Thanks for the kudos, folks! Let's hope these suggestions help kfp673 and others facing this, or similar issues.

BTW, for those who haven't seen my images and posts by now, here's a pair of links to my motorhome project pages:
2000 Four Winds 5000 26Q
2016 Sunseeker 2250SLEC

Enjoy!

Excellent job BruceMC

StirCrazy wrote:
if there is access you could also inject a low expansion foam into the voids to create that stability. I have seen that done before.

Steve

I am not opposed to this idea but the space is roughly 4" tall. I am not aware of foam (unless I use 10 cans) that expands that large. For now I cut a collection of pieces of 2x6 and 2x4 and added support in different areas I can reach. Towing it this weekend so I will see how it holds up. Definitely much better than it was but not perfect. I'll see how it goes.

Thanks all!

if there is access you could also inject a low expansion foam into the voids to create that stability. I have seen that done before.

Steve

Outback 277RL: I cut some small pieces of 2x2 to just the right length and glued them on end under the shower pan to support it. Then I replaced the plastic fitting on the shower with a rubber adapter and clamp. Took about an hour and didn’t have to remove anything. Never leaked another drop and was solid to stand on the 8 years we had it.

Thanks for the replies, and nice job Bruce! After looking at some of those videos it seems people do a range of full removal and rebuild like Bruce to simply cutting pieces of wood and stacking them to create support. Similar to some of the videos, the reason I even looked at this is our shower drain was leaking. Saw it dripping from the underside of the camper. I removed the access panel and reached in to make sure all of the PVC nuts for the drain pipe connections were tight and they seem to be. And, it only seems to leak when my wife or I are in the shower. When my 70lb daughter is showering it does not leak, so I am convinced the flexing is casing the leak. Ironically our dealer just completely resealed our shower seams due to a **** job done by the factory, so I would prefer not to pull it if I can. Going to try some of the other options first knowing that I can always pull it out and rebuild if needed. Thanks again!

I did the same as Brucemc. Just rebuilt the whole thing, and installing a full plywood base. I also added spray foam where I could (edges only)

On our old 2000 Four Winds, the support under the basin was, shall I say, very poorly designed and installed. I had to remove the shower walls and the basin to gain access to the area, so I installed new framing and a large piece of 1/2" plywood at the proper grade, then drilled a hole sufficient for the drain, then reinstalled & sealed the entire structure.

Original base:



Yes, that was all that was under the shower base:



New framing:



We used that unit for 5 years w/o an issue. I liked that shower... it's 1 1/2 times the size of our current shower in the Sunseeker.

Bottom line, to get sufficient support, you'll probably need to go to the effort of removing the liner and base to access the support structure (or lack thereof), and properly rebuild it.

Clicky

Those ideas seem non applicable to a RV. The mortar idea is out, it needs a solid base itself. Shims do not apply and filling the space with foam would mean never being able to get at the piping again.

The videos here specifically for RV's may have an answer. I have the same issue myself:
RV Shower floor fixes

How old is your camper? My Jayco had a similar issue. The plywood base only covered about 2/3's of the width of the shower pan, so if you stepped on that 1/3, it flexed and scared me. Turns out that the flexing actually allowed the drain to come loose and caused a leak at that connection.

Thankfully I was under warranty. They removed the shower, installed a new piece of plywood and stiffened it right up. Fixed it 100%. Without seeing actual pictures of yours, I would imagine the fix will be the same. Remove the entire shower/tub and install the support with the correct size hole.

If you have room from below, you could cut a new piece of plywood to fit the oversized hole (like a patch) and cut it in half. Slide one side in, then the other side so that the patch is flush with the floor and the plywood. Then use a larger size piece of plywood underneath the existing plywood and patch, and use a strong poly adhesive to adhere it.

That would be the only way I could think of about attacking it from below, if there was enough room.