Leaking tub/shower 2nd floor

[Boblvl]

I have an upstairs bath that has been leaking through my ceiling from downstairs. I have used silicone, bought door enclosures nothing worked., I cut a hole in the sheetrock to the wall where the plumbing is so I can see where the leak is coming from. I can also see the bottom of the tub since my ceiling under it is cut out from the leak. The leak is coming from where the tub meets the tile wall. It is a tight fit but I can see that it has a metal frame and not sure if the tub is supported coorectly or not since I just bought this house. I know that it has to be when the tub is full that it is pulling from the wall becasue it only leaks when my son is taking a shower. I don't know what to caulk it with how how to make it not move. Any suggestions?

 

[opps]

Is the shower head fixed?

If yes then the leak could be at the elbow in the wall where it meets the shower arm.

To test it remove the shower head (from the fixed arm) and turn it on. The water should now be falling into the bath and not hitting the walls/screen.

Provided that the leak is not from the trap then it can only be from the supply up to the head.

If it is from where the fixed head arm enters the wall then you can unscrew it and use LSX

 

[Boblvl]

It isn't the plumbing at all. The pipes and shower are totally dry to the touch from any leakage. As I stated earlier I can see where it is coming from. When the water hits the wall while showering and runs down to the tub it sits on the tub and it leaks where the tub meets the tile. The bottom row of tile sit on the tub and that is where the leak is. It only leaks while he is showering in it. If the tub runs and is full it does not leak, if you turn on the shower with no one in it then it doesn't leak. It only leaks when the weight of someone is in it. Which means the tub is moving from the wall. I have siliconed it many times to fail.

 

[john306]

Is there any way to easily get underneath bath and
a) reinforce floor if it's flexing too much
b) secure battons to wall/build frame to support bath where it is dropping.
Only then will the sealant stay in place

 

[misterhelpful]

Other than doing what has already been suggested by john306 and supporting the bath from below (best option), a simple method that may work is to remove the existing sealant, clean the area and fill the bath with water to weigh it down, then reseal (ensuring the area sealed is dry first). Leave this to dry completely before emptying the bath and hopefully this will allow the sealant to stay watertight with the weight of a person standing in the tub to shower.
Of course, if there is excessive movement, this method is not guaranteed to work and you will be left with little option other than to do as already suggested or remove the bottom course of tiles and use a tiling upstand before re-fixing them.

One point to remember is that most silicone based sealants will not adhere to themselves very well and so applying over the existing means it is still likely to fail.

 

[ic1927]

This is a common problem caused by the bath not being sealed to the wall with silicone prior to tiling. I know it's a bit of a job but your best bet maybe to remove the bottom row of tiles that sit on the bath and seal the gap with silicone, then re-tile and grout and when dry seal again with silicone, as Mr. H said, fill the bath with water before applying the silicone.

 

[Boblvl]

I do appreciate all of your suggestions. I really can't get underneath the tub to support it. I do know that it is a cast iron tub. Pretty sturdy. I removed all of the old silicone, weighted the tub down, filled it with water and then re sealed it with silicone again. Figured I would wait a few days before letting the water out and see if it helps.