Small cracks in bottom of tub

[owenb_]

This tub is on the 2nd floor above our garage. We noticed water leaking from the garage ceiling directly beneath it last time we used it. Water did not appear to be leaking from the drain area. I noticed some small cracks on the bottom of the tub which I suspect may be the culprit. Is this repairable (using some kind of epoxy, sealer, etc)?

Thanks in advance,

 

[Twowaxhack]

I would replace the tub. A repair even if available is throwing good money and time out the window. Kicking the can down the road at best.

 

[breplum]

Unless you have full direct view of the underside, you can't diagnose properly because water travels wildly.
Fiberglass is layered, and yes, those cracks forebode a failure, but maybe not all the way through. It is possible it may come from elsewhere.

 

[RickFlorida]

There's now way you can repair that tub. You have to replace it. Sorry for the bad news.
But here's why this one probably cracked. It didn't have a mortar bed underneath it which not only helps quiet the tub/shower pan and make it feel more solid, but a mortar bed would have probably prevented it from cracking like that. But I have the luxury of solid terrazo floors in Florida. (concrete floors). Without access below, it might make installing tubs and showers a nightmare to plumbers from up North but the benefit is that if you lay a nice mortar bed down, the acrylic/fiberglass tubs will feel like a 500 pound solid tub.

 

[GymBag]

If the tub is removed, you may find that something leaked and caused the underlayment to fail, which removed the tub's support under the area where it cracked. The tub is probably a symptom of the real problem.

 

[RickFlorida]

If the tub is removed, you may find that something leaked and caused the underlayment to fail, which removed the tub's support under the area where it cracked. The tub is probably a symptom of the real problem.

Exactly , unless it's super old acrylic/fiberglass and just cracked due to age which of course could happen, it's more likely that it's not supported underneath. One of the best things about my old single floor block Florida home is that we can easily support acrylic/fiberglass tubs and shower pans with a mortar bed directly on solid concreted terrazo. I don't know how you can correctly support an acrylic tub or shower pan on a soft wood floor. So even the best install probably doesn't last up North because of that?

I usually just need 3/4 of a 50 pound bag of mortar and I make a "bed" of it and then push the acrylic tub or shower pan onto it and level it out. Makes for a SUPER solid feel like it's a real solid tub. The fun part though is with no basement, we have to have a access panel behind the wall where the tub spout is so we can make sure there are no leaks and the waste pipe is connected correctly. Fun times!

 

[Twowaxhack]

Exactly , unless it's super old acrylic/fiberglass and just cracked due to age which of course could happen, it's more likely that it's not supported underneath. One of the best things about my old single floor block Florida home is that we can easily support acrylic/fiberglass tubs and shower pans with a mortar bed directly on solid concreted terrazo. I don't know how you can correctly support an acrylic tub or shower pan on a soft wood floor. So even the best install probably doesn't last up North because of that?

I usually just need 3/4 of a 50 pound bag of mortar and I make a "bed" of it and then push the acrylic tub or shower pan onto it and level it out. Makes for a SUPER solid feel like it's a real solid tub. The fun part though is with no basement, we have to have a access panel behind the wall where the tub spout is so we can make sure there are no leaks and the waste pipe is connected correctly. Fun times!

I install mortar beds on wood subfloors. I usually put down some concrete board then slap down a soupy sand mix concrete product. Then set the fixture and let it dry over a weekend.

 

[GymBag]

If it's actually fiberglass, it cracks can be repaired, but there's not really much point if they occurred because of a lack of support under that area. For this reason, I mentioned inspecting the flooring underneath the tub.

Fiberglass is relatively easy to repair and if gelcoat was used, it'snot hard to find the color code if the tub manufacturer is still in business. However, the color may not be exact after years of use and exposure to cleaning chemicals, especially if bleach was used. That isn't the end of the world, though- the bottom can be taped off and a complementary color used as an accent. Also, several types of non-skid are available and since these are both used extensively on boats, YouTube has videos that show how to repair and refinish it.

Some people repaint boats with Epoxy with products from brands like AwlGrip, TotalBoat, Pettit and AlexSeal.

 

[pakle]

You can try a "Bathtub Floor Repair Inlay Kit" like this as a last ditch effort:
https://www.homedepot.com/p/16-in-W...air-Inlay-Kit-White-INLAY-WT-1640-1/206410512
But your best bet is follow the advice of the above experts to replace the bathtub if the cracks are due to insufficient support underneath.

 

[GymBag]

You can try a "Bathtub Floor Repair Inlay Kit" like this as a last ditch effort:
https://www.homedepot.com/p/16-in-W...air-Inlay-Kit-White-INLAY-WT-1640-1/206410512
But your best bet is follow the advice of the above experts to replace the bathtub if the cracks are due to insufficient support underneath.

Structural fiberglass repairs can be made, but the cause needs to be found and corrected, if the tub is worth saving. The repairs are done regularly to fiberglass boats, small and large. Done right, it's at least as strong as the original layup and finishing the surface isn't terribly difficult, but that needs to be done right, too.

 

[Twowaxhack]

Most anything can be repaired but is it worth repairing is the question.

 

[GymBag]

Most anything can be repaired but is it worth repairing is the question.

Exactly!

 

[RickFlorida]

Yeah it's a tough situation if someone doesn't have the time to do it themselves (rip out the tub and wall kit and install a new one, and then mud it nice into the wall, just finding out what kind of corner bead they use was hard for a DIY person like me. (they make super wide corner bead type plastic you can use to rough in the acrylic or fiberglass tub and shower walls). It took me a long time to get it all done myself but luckily I have a second bathroom like most people do.

Where I live in my part of Florida, NO ONE who does decent work for kitchens or bathrooms will do a small job and they quote very, very high because so many cash buyers are moving to Florida, or buying the homes to rent them out.

I'm very lucky in that I have more time than most working adults, so I use my time to do my own repairs which is good because I don't have enough money to pay the insane quotes you will get for what would only take a professional 1.5 days at most to do.

 

[Twowaxhack]

Yeah it's a tough situation if someone doesn't have the time to do it themselves (rip out the tub and wall kit and install a new one, and then mud it nice into the wall, just finding out what kind of corner bead they use was hard for a DIY person like me. (they make super wide corner bead type plastic you can use to rough in the acrylic or fiberglass tub and shower walls). It took me a long time to get it all done myself but luckily I have a second bathroom like most people do.

Where I live in my part of Florida, NO ONE who does decent work for kitchens or bathrooms will do a small job and they quote very, very high because so many cash buyers are moving to Florida, or buying the homes to rent them out.

I'm very lucky in that I have more time than most working adults, so I use my time to do my own repairs which is good because I don't have enough money to pay the insane quotes you will get for what would only take a professional 1.5 days at most to do.

I charge roughly $6k to remove a standard bathtub and install a 5’ shower in its place. That’s with basic materials, nothing special. Cultured marble shower and walls. Drywall work, paint and floor work to be done by others.

For another $600 I’ll furnish and install a handicap toilet.

 

[Bird Doo Head]

GymBag mentioned repairing the tub. It works.

We have a Kohler Greek fiberglass that I bought 30+ years ago from the local supply house. They dropped it off the fork truck. The bottom and a corner broke. They sent it to an auto body shop and they fixed it. (And the wholesaler gave the tub to me for chump change.)

From the user side, one can not tell it was repaired- even 30 some years later.

Paul
PS: I set it in a bed of peralite. which is a lightweight scratch coat for plastering.

 

[GymBag]

GymBag mentioned repairing the tub. It works.

We have a Kohler Greek fiberglass that I bought 30+ years ago from the local supply house. They dropped it off the fork truck. The bottom and a corner broke. They sent it to an auto body shop and they fixed it. (And the wholesaler gave the tub to me for chump change.)

From the user side, one can not tell it was repaired- even 30 some years later.

Paul
PS: I set it in a bed of peralite. which is a lightweight scratch coat for plastering.

Auto repair or boat hull repair- either can do it.

Still, it should come out to make sure any wood underneath is dry and undamaged. The tub shouldn't have cracked if it had been well supported from below and I don't think that's the case.

 

[Ludington]

Does it flex when you stand in it ? If so, you really need to get something under it to stop it. Or any repair is going to fail.

 

[Bird Doo Head]

Does it flex when you stand in it ? If so, you really need to get something under it to stop it. Or any repair is going to fail.

Pearlite based scratch coat (or "Gauging") plaster is the bed into which I set our fiberglass tub. It is primarily made of peralite and is very lightweight. There was a brand called Pearlite, but it's gone from the market. Gold Bond Gypsolite, Hesperlite, USG Red Top are all similar substitutes.

I made the bed deep enough that the mud squished up the sides of the tub a bit, making a cradle. There are no air gaps on the bottom.

There is no flex at all. I've had guests ask where we got a deep, four foot cast iron tub. It's that solid.

Hint- With clean shoes or feet, working inside the tub helps push it down in the mud and makes it easier to view the levels as you work. When you get close to where you want it, you can connect the drain plumbing and fill the tub with cool water to help hold it in place. (Don't use hot water. The mud heats as it cures and adding heat will over-speed the curing, making it weak.)

If the tub is in place, perhaps you can reach under it from the plumbing access chase and push plaster under the tub.

Paul

 

[Ludington]

We havnt heard back from the op......