I have a fiberglass tub on the second floor that appears to have water seaping out of it from the one corner. Whenever someone takes a bath the outside corner of the tub is wet. Eventually enough water comes out and soaks the first floor ceiling. I do not see any cracks of any type in the tub. I would guess the tub is about 15-20 years old. Is it possible for the fiberglass to allow water to soak through?

How do you know it's coming out of a corner when there are no cracks?

15-20 year old tub, it is possible that the seal around the drain is leaking not a corner.

You can un-screw the drain and see if the seal is cracked.
Needle nose pliers work or a drain wrench.

When you re-seal it, clean any old seal, then use alcohol to clean both the bath and drain, use silicone for bathroom, then re-screw the drain. Don't over tighten, do use for 24 hrs.

Hope this helps your problem.

Gerry

I don't believe it is the drain because the only place it is wet is on the outside corner.

If you push down on tub floor, it may open up a crack.

Is it a bath or shower when it leaks?

If the floor is not totally level water could run to that corner.

It could be a lot of things. Tap leaking when turned on, shower up pipe.

Try this clean round the drain, silicone around drain. without removing. If this stop the problem repair as I said before as this is only a quick fix for drain leaking.

There are companies around that re-do all tubs but are expensive

Okay, so the ceiling below tub is already ruined? Going to have to cut it out and repair eventually. So why not just cut out the ceiling now and find exactly where the leak is coming from. Best of luck, and please let us know what you find.

If your overflow is leaking, it may be running down tub to one area or another causing decieving wet spot.

I have had similar problem but I had cracked in the tub that leaked through to the sealing below. I have since had the tub refinished which is expensive$$'s but still cheaper then getting the tub replaced since to do that it would also mean breaking a wall to get the old tub out and new tub in. Not being a handy guy myself didn't want to spend the money. My concern is on the sealing below where we saw the leak I was planning on spraying killz to fix the patch would that do the trick?