You are here:

Flooring and Carpeting/how to address thinning grout


QUESTION: The grout is worn/thin in some spots of my river rock shower floor, notably in the spot where showers users tend to stand under the showerhead.  There are no visible cracks in the grout and so far no trouble with drainage, which suggests to me that there is no water penetration/damage but rather usual wear and tear.  Is it safe to patch new grout over the existing grout in thinned areas of the shower floor (and then promptly reseal) to prevent further wear or would this cause other problems later? When do I need to consider  complete overhaul of the grout/flooring?

ANSWER: Thank you for your question Virginia,

    Once the actual grout is wearing away the process is only going to accelerate. Just because you can't visibly see a defined crack doesn't by any means imply that there isn't water passing through "along" the rocks themselves and not in the grout per se', so it is something that bears watching. The notion that you can grout over the existing grout has been around for decades but seldom proves out Virginia. What typically happens is that the fresh grout simply can not bond properly with the old grout and soon thereafter begins the process of the new grout cracking out as it just won't stay in place. Being within the wet area there is going to be the constant wearing of the weaker/softer grout surrounding the harder more resistive rocks. As long as the floor is performing without a failure then you will only need endure the "visual" aspect of how the floor appears...but I suspect that sooner rather than later you will need to consider remodeling the space. Perhaps you can start now by setting aside a little each month and continue as long as the shower floor hangs in there and by the time you have enough to complete the redo you will have received all you could have from the original floor. That would be all you could expect from it. Ok Virginia I hope this helps you with your project, feel free to return anytime...

Perry V.

---------- FOLLOW-UP ----------

QUESTION: Thank you so much for your detailed response, Perry.  
This all makes sense.  We can definitely endure the look of the thinning grout.  So in the meantime, we should keep sealing the shower floor grout until it goes or we remodel space?

Thanks for returning Virginia...

    Of course the answer is yes. Sealing will slow or perhaps even hold the current condition of your floor for a longer period of time. Keep in mind though that when you seal this area you will need to do two things. First is you will be required to stop using the shower for at least a week. Because the shower floor is porous and it's current condition may be even more so than a new version it will need to dry out "down to the bottom" of the assembly. Any lingering moisture can and will affect both the appearance and performance of the effort you make. When a sealer comes in contact with moisture it will almost always turn white or milky and that is how it will dry so then you will be faced with looking at that for a very long time. Secondly is you should wait at least 3 days after a second coat for things to cure and thoroughly dry. (Yes...two coats). So in affect you are going to need to put your shower out of action for about two weeks if you want this process to have it's best shot at being successful. In a wet area space you should consider performing this task about every 10 months if used on a daily basis. Any longer and you will lose the performance factor of the product...follow me? Ok Virginia I hope this helps you with your project, feel free to return anytime...


Flooring and Carpeting

All Answers

Answers by Expert:

Ask Experts


Perry Vellenga


Ceramic Tile/Marble. I can answer questions about floor preparation, tile selection, layout questions, performance of products, expectations of finish, compatabilities, questions about grout and epoxies, evaluating an installer, asking the right questions to check competence...more? 33 years this August 2012/ many years in commercial application from exterior finishes to Mall store fronts/ interior finishes like floor packages in stores inside Malls examples: The Limited, Lerner/NY, Lane Bryants, Bombay Co., Now involved in Residential new construction covering all types of interior finishes and designs.


I worked in an exclusive field of floorcovering called "Tenant Development" which is by invitational bid only, by way of a National bid list. These are large floor packages usually over 3500 sq. ft. of 18" x 18" Marble and Granite and many other types of Marble and sizes. They are specialty stores where the floor package can cost upwards of $50,000 for one store. I have also done "Structure" stores and J. Riggins stores, Lane Bryant,Express and Body Shop stores where wood flooring is used. Presently work for a National Flooring Company in the Residential new construction arena that covers most interior design elements..Granite Slab tops/wood flooring both job finished and prefinished ect..

My response's are published all across the Internet and picked up by multiple Interior Design sites and Industry related web sites where people have questions...

too many most of which don't count...

©2017 All rights reserved.