Tub Caulking from hell

[brats.n.harleys]

We bought our home 2 years ago and it was "flipped". They did a nice job on everything. After a couple months the caulk around the tub and surround was molding bad. So I ripped it out and found that either the surround or tub was put is crooked. There is some spots that have 3/8 inch between and some points are close. It's not noticeable unless the caulk is removed. Well it's getting moldy again(mold proof caulk). Anyone have any suggestions. I don't want to take out the bath or surround but is there a product to pre fill the gap with or a caulk someone has used that truly is mold proof. Also one that is quick dying? It's our only shower and hard to find a 24 hour period where no one needs a bath/shower. Thanks.

I know this has nothing to do with a garage but someone has to have done it

 

[Mattlt]

Sounds like they F-d up the insulation and vapor barrier behind the tub surround. I'm also going to guess they didn't use the green water-resistant drywall behind it.

I don't think you're going to be happy with a short-term fix. (I've been watching too much Holmes on Homes!)

 

[ddawg16]

Have you tried Silicon caulk? Most of the bathroom caulk you get is water based....and in most cases is "mold resistant"...not mold proof.

I would try it with silicon....downside...takes a lot longer to dry.

Is the mold in the inside as well? If it's just on the outside where it is exposed to the bath then I think your issue is just the caulk.

 

[dolfans]

I have the same problem with the caulk and the time. I have only 1 tub also and 5 people for a shower

 

[jeffk14]

Have you tried Silicon caulk? Most of the bathroom caulk you get is water based....and in most cases is "mold resistant"...not mold proof.

I would try it with silicon....downside...takes a lot longer to dry.

Is the mold in the inside as well? If it's just on the outside where it is exposed to the bath then I think your issue is just the caulk.

What he said. Get "100% silicone" caulk. Only downside is that you'll need to get whatever color you want it to be. 100% silicone doesn't take paint very well.

 

[wbclassics]

I'm pretty sure DAP3.0 is silicone based and can get wet within 3 hours. About $7/tube IIRC.

Also this GE Silicone product (1hour until wet use)

 

[fourfeathers]

Mold problem or mildew?

 

[brats.n.harleys]

Hmm I guess mold. It just gets black and can't be scrubbed off. So silicone will not mold or mildew but takes longer to dry. So maybe after everyone showers on a Sunday morning, re apply some silicone and it should be good Monday morn.

 

[bgott]

They make foam backing strips to fill in excessive gaps before you caulk. It won't stop mold but it will save the caulk and aggrevation of filling the gaps.

Google "caulk backer rod".

http://www.dap.com/images/products/hires/356_p_CaulkBackerRod.jpg

 

[Jack90210]

Here is a good page on caulking a tub surround. FWIW, I too am a fan of "Polyseamseal" (which is recommended in the linked article).

Silicone will grow mold, too. Even the bathroom-rated stuff.

 

[e-tek]

You're going to have to go AT LEAST one day with NO showers! It really NEEDS to be dried and dry prior to application for best results. I'd sugegst everyone SKIP Sunday mornings shower - or go to the pool/neighbour/friends house....
On Saturday, after the showers, scrape the old caulking, then put a fan and/or heater in there to facilitate drying. Let it dry all day and night. Caulk it the next (Sunday) morning. Let dry until Monday morning showers.

I just read that link from Jack above and it also says silicone caulk HAS to be BONE DRY for proper applicaton. As well, I think the mold is partly coming from the moisture you are continually re-sealing under it.

 

[jj mack]

I have been in the adhesive and sealant business for 18 years. I have also had a screwed up shower that was originally installed wrong.

Most sealants are not designed to span 3/8". as suggested a 100% solids material such as silicone, polyether or even a polyurethane will work much better than a latex or "siliconized acrylic".

But for any of them to work, you need a backer material to fill the void.

The second point is... a fillet bead (inserted into a 90 degree corner) is the most difficult type joint. Sealants have elongation, but when placed in a corner, movement causes infinite force on the bond line and they fail. In a corner, there is no way for the sealant to elongate. It can be done with bond breaker tape...but that is a long discussion for larger joints.

This is why so much tube and tile caulk is sold. It always fails

I tell you this because you are putting a band aid on a problem. I am 95% sure that whatever you put there will also fail and cause water damage. It really needs to be fixed properly, tube reset, tile and drywall redone.

If you are set on repairing it. Fill the void and use a 100% solids product. Keep in mind that if you go with silicone, another silicone used to touch up later or recaulk later, will not stick, nor is it paintable.

Substate prep is very important. you need a clean dry sound substrate.

Go to the tile store and see if you can get a trim pieces (that will look right) and glue them over the joint with the same sealant. This will serve as protection to keep water away from the problem area. When you glue it on, the idea is to apply the sealant at the outer edges of the trim, and do not compress it and squeeze all the sealant out, you want the sealant to end up ~1/16 to ~1/8 thick so it can accommodate movement with out failing.

Good luck!

jj