Bathtub drain leak: how do I know if it is something OTHER than bad putty?

[funperro]

Hey guys... quick question: I've got a tub leak that I noticed last night. Today I filled the tub up full and let it sit for 4 hrs to test if there was a leak around the outside rim of the drain. Not a single drop came through the leak spot in the room below during this time. As soon as I started draining the full tub, the leak started and was fairly strong. The leak stopped a few minutes after the tub was drained. I've never fixed one of these before... but from what I understand, the full tub test is actually testing the putty seal, is it not? If the putty was bad, it would've leaked the whole time, no? If I am wrong, that is good news since it is an easy fix (just get new putty). If my thinking is on the right track, then what do I need to do to fix this leak? I'm assuming it has something to do with one of the pipes' connection to the drain.

Any help is much appreciated.

Thoughts? Suggestions?

 

[Kreemoweet]

Unless your tub is very very very old, the seal at the tub outlet is effected by
a rubber washer, not putty. Clearly your leak is occurring past whatever mechanism
it is that keeps water from draining. You'll have to access your tub drain somehow
and have a look.

 

[Sponsor]

 

[Jimbo]

Typically, the putty seal around the flange keeps the tub from draining when the stopper is closed. It the putty fails, water leaks from the tub INTO the drain, but NOT onto the ceiling. Your symptom indicate a faulty rubber gasket under the tub, or a leak in a joint in the piping.

 

[hj]

The putty just keeps the water IN the tub. It has NOTHING to do with preventing leaks under the tub. You could even install the waste without putty, or anything else, and it would still not leak UNDER the tub. BUT, you have to find out WHERE it is leaking, before you can even try to repair the leak.

 

[Terry]

I'll bet you a cup of coffee that I could install a tub drain with only the rubber washer and it would never leak.

 

[hj]

IF you can't you had better hang up your plumber's shoes, because that is the ONLY way they can be installed.

 

[Ballvalve]

If its rough fiberglas tub, seems like some putty or silicone is due on top the rubber gasket.

 

[Terry]

You do not want anything on the rubber gasket. That is what hj and I are talking about.
You want a clean rubber seal between the tub and the shoe.
Silicone goo or putty create a small gap that allows water to seep through.
Collectively, hj and I have been doing this for almost 90 years.

 

[Ballvalve]

Wouldnt silicone act just like gasket cement on your oil pan?

I speak only of ROUGH fiberglas

 

[hj]

It the tub has "rough fiberglass" at the drain outlet, then it is a "defective" tub. The surface under, and around, the drain opening MUST be flat, smooth, and parallel to the tub's surface.

 

[Ballvalve]

You havent seen the crap they sell lately...... I could put a finger through the shower/valve wall [one piece unit - Lasco] wall. Took 2 hours, 4 tubes of glue and a ton of wood to keep someone from putting their foot thru the phony tile junk.

Steel, iron, cast plastic, no problem.

 

[hj]

quote; I could put a finger through the shower/valve wall [one piece unit - Lasco] wall. Took 2 hours, 4 tubes of glue and a ton of wood to keep someone from putting their foot thru the phony tile junk.

If their "foot" is hitting the wall, then you have a user problem, as well as a cheap unit.

 

[Ballvalve]

You may remember in your old days what went on with couples in bathtubs. Beyond me now too, but They still do it, and it puts a lot of pressure on the end walls.

When we hung 600 hotel bathroom sinks and tops and build up, the design criteria was for a 400 pound womans butt bouncing up and down
[calesthenics?] on the center of the double sink run skirt.

I dont see any thick wall offerings in the Lasco one piece book.

 

[Presence]

You do not want anything on the rubber gasket.

You want a clean rubber seal between the tub and the shoe.

Silicone goo or putty create a small gap that allows water to seep through.

It the tub has "rough fiberglass" at the drain outlet, then it is a "defective" tub.

The surface under, and around, the drain opening MUST be flat, smooth, and parallel to the tub's surface.

Well and good. I agree.

But here's my situation....

DEFECTIVE GLASS TUB; DRAIN FLANGE NOT FACTORY SMOOTH.


Little Old Lady, fixed income; I need to patch this situation up for her for under $150. Call it "defective" and get a new tub enclosure is not an option.

Very Minimal Access. I have a 16x40 opening from floor up in the tiny towel closet behind the tub; I have trouble getting into the closet. The subfloor around the drain is cut out really close to my drain pipes; I agonize at the thought of attempting to reciprocate in there.

No way I'm getting a 4" grinder in there to to flatten the flange without causing extensive damage to custom plaster work or rebuilding the closet. I have no intention of involving myself in this and she doesn't have the budget. No access from below without removing finished work: custom cabinets, crown moulding, etc. etc. Custom finished fancy plaster work; I don't want to have to talk her into a hole in the ceiling that I or another contractor will need to repair.

Fiberglass drain flange is factory rough; aka "defective". Previous plumber used "plumbers putty" between the bottom gasket and the unfinished rough glass on the bottom side of the tub where there should be no putty or silicone... just a gasket as you've stated. As expected, plumber's putty has since degraded... major drain leak; causing minor damage to ceilings below, which is still reconcilable without tear down.

Currently a screw together PVC type drain assembly w/ lever. I could be talked into brass replacement.

Thoughts on epoxy or glass resin and clamping it shut w/ rubber gasket while wet/hot?

3M 5200 Marine Sealant?
Vulkem 116 Sealant?
DAP Butyl-Flex 27062?
X-Pando?
Hercules 15703 Blue Block?
Phenoseal?

Open to suggestions. "Applied Product" preferred. I can get in there with a sanding block and probably knock the high spots but it will likely never be a factory "flat, smooth, and parallel".

I'm leaning "hand sand it", "brass trap", "double rubber gasket", and plenty of "Hercules 15703".

Thoughts?

 

[hj]

the problem is probably a "groove" not a "ridge" so sanding would be useless
"double gaskets' would NOT squeeze in to a groove any better than a single one.
You may have to settle on a bead of silicone on top of the gasket.

 

[JohnfrWhipple]

...You may have to settle on a bead of silicone on top of the gasket.

Now we are talking. That's how I like to see them done.

Over kill

 

[Hetesh]

The putty just keeps the water IN the tub. It has NOTHING to do with preventing leaks under the tub. You could even install the waste without putty, or anything else, and it would still not leak UNDER the tub. BUT, you have to find out WHERE it is leaking, before you can even try to repair the leak.

If I may ask, when I run water down the bathtub drain I smell the smell of sewage; there's a light brown ring around the dark brown flange; twice I've cleaned the tub and when I wipe around the flange material (putty?) comes out. I first checked the drain relief & found it's not properly installed with the hole its hole, & the gasket has been partially eaten & fallen off. From reading this forum I understand that the putty below the flange has nothing to do with preventing leaks, but functions to hold water in the tub. If the party seal has degraded, water would leak into the drain pipe, not the floor below the tub. Water collects below the tub if the pipe itself or the seal connecting the tub drain & pipe were leaking or had degraded, correct?

Thanks, HP

 

[Terry]

Part 1 is the foam gasket for the tub overflow. If the water is high enough in the tub, water can leak past the gasket.

Part 10 is the rubber gasket under the tub and seals the tub shoe. This is what keeps water from leaking below the tub.

In this picture, part 7 is the stopper that either holds water in the tub, or is raised to allow it to drain out.

In this picture, part 6 is the rubber seal.

No putty on the rubber seal, some putty under the flange. Not that the putty does anything though.

 

[FullySprinklered]

You're barking up the wrong tree. Redo the drain with a new good quality gasket while you're there, but the dripping after the water runs out would indicate a leak further down. And since it keeps dripping for a while after the tub runs out, possibly at the trap. Water running out will suck air into the pipe and not drip until the flow diminishes. I use putty.