Rotting Grout in OLD Bathroom

JessInTime · 01-22-2009, 01:13 AM

Hello All,

I'm brand new to this and am currently unemployed. This gives me a lot of time to sit around and think of how to better this old home. The house is from the 1920's or so and has been added on through the years. We're concerned on how to replace the tiles in our bathroom.

The grout is currently black in our bathroom and the glue has started to squeeze through the tiles. I think we're afraid to look behind the tiles since we suspect mold. I've taken tiles off of another bathroom elsewhere in the house and it seems like the backing is plaster. I'm wondering if this was normal for "back in the day"? If so, can liquid nails hold the new plastic surround up to the plaster?

As for the molded grout....should we take out all of the tiles and just replace with a plastic surround like the other bathroom? We also don't have any fans in the bathrooms and I can only assume that that is one of the reasons for the mold.

Please help. We are limited with money and if there's anything I can do on my own, it would make me feel a little more helpful.

Thanks, Jess

Bob Mariani · 01-22-2009, 06:38 AM

Replacing the grout may be a short term fix only. But an important first step is to get good ventilation into that bath. Anything you do will be a problem if moisture is not removed. Remove the tiles if you plan on any correct fix. Add the proper backing (CBU) and waterproofing if you tile again. Do it right even with a limited budget.

JessInTime · 01-22-2009, 07:28 AM

Thank you for the response. I'm anxious to get started and worried that I'll mess something up. I know we'll be in major trouble if the joists are molded behind the wall as well. Could you tell me what CBU is? And instead of retiling, I'm thinking of putting in another surround, will that hold with liquid nails when the shower causes steam?

Sorry for the questions, I'm really new to this. I'll be going to Lowe's to price the things I need and ask fir some direction there too.

Thanks Again,
Jess

Bob Mariani · 01-22-2009, 07:35 AM

CBU is a Cement Backer Underlayment. Available in 1/4" and 1/2" thickness. It is used behind tile to provide the proper surface for tile adhesion. It does not add waterproofing or structural integrity. You could use a moisture resistant drywall or paperless drywall behind the tub/shower surround and use a glue that is suggested by the manufacturer of this product. Different ones may need different adhesives. But the cheap ones are glued. Better ones, which is the only one I could reccomend are bolted together at the corners and come in three pieces.

angus242 · 01-22-2009, 08:06 AM

Unfortunately with a house that old, you're bound to have "issues" behind the walls in the bathroom. I have remodeled bathrooms under 5 years old and they have been moldy. Your best bet is to tear down as much of the tile/walls around the bathroom as you can. You're probably going to find things you wish you hadn't but now's the time to take care of it. Mold and rot don't take care of themselves.
Certain surrounds will get attached directly to the studs anyway. Depends on what your purchase. I think one of those surround units will be the best choice right now while still allowing you to see what's going on behind the walls. Just be prepared or have the budget to start replacing rotted wood should you find it.

And by all means, try as hard as you can to get some ventilation fans in those baths!

JessInTime · 01-23-2009, 05:34 AM

Thanks so much for the responses. I appreciate it. The best part is that we'll be getting a roommate soon and that will help with the costs. Thanks again!