Bathroom Remodel

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Posted by: from St Joachim
2/24/2012 at 12:00:31 PM


We have recently remolded our bathroom we put in a new tub and put in the Durock Cement board in and put nice tiles on the wall everything was done correct and we sealed all the tiles and grout . We had used a clear water resistant caulking at the bottom where the tub & tile meet. Well it now looks like the clear caulking is molding (it's black and spotty). I am not sure what we should do.

Could someone please give me some advice?


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Date/Time2/24/2012 at 1:13:57 PM

Hi Sherry! Do you know if the caulking is mold resistant? You need to use a mold resistant caulking in the bathroom. Might be all it is. Check for leaks underneath as well might be that the drain of the tub is not tight enough and is leaking. Also around your taps as well might be seeping thru. Just some food for thought hope it helps.


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Date/Time2/24/2012 at 1:18:01 PM

As I suspect the same. You can buy Microban caulking at any home improvement store. This caulking is designed for kitchen/bathroom use and does not mold over time. In order to get good clean caulk lines you can also purchase kits that are designed to spread the caulking out if you find this might be helpful for you. Before putting down the Microban caulking make sure that you scrap all of the existing moldy caulking off. If it's really stuck on I have found that an exacto knife sometimes works the best.

Best of luck with it!


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Date/Time2/25/2012 at 7:27:20 AM

Like the other replies above, we suspect that you may not have used 100% silicone specified specifically for wet areas with a fungicide to prevent mould growth. Prior to applying the silicone, the area should be cleaned first with Concrobium Mold Control.


Kingsway Construction Inc

Glenn Rosborough

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Date/Time2/25/2012 at 11:00:42 AM

You must have quite a bit of moisture that lingers for more than a day. How is your Bathroom Fan? Might be time for a new fan aswell. You should remove the current Silicone and re-apply a Kitchen and Bath silicone. If you only have a window in your bathroom to get that moisture out that might not be enough.

The only other possilbe cause it might be is what might be in your water. Black staining is caused by Manganese. To treat this condition you would need to install a Whole House Manganese greensand Filter.


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Sherry in St Joachim
Date/Time2/27/2012 at 11:19:45 AM

Thank you everyone for the help

I thought we had purchased the correct caulking but I guess we were wrong.

Dominic: We have just replaced our fan a couple of days ago this could have been part of the cause.

I guess I have a project this weekend! I will take all of your advice

Thank you again!

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