Flooring and Carpeting/bathroom floor


bathroom floor
bathroom floor  

A few weeks ago, we noticed our toilet was leaking around the base. upon removing it I discovered that it must have been leaking for quite a while based on the condition of the flooring and the presence of mold and mildew. Under the top layer of linoleum tile (which is all I had ever seen, we've just been in the house 3 years), I discovered a layer of pergo-type laminate flooring, the green pad the pergo sits on, and under that about a 1/2 inch of something I'm not sure about. Under that is the concrete slab. The 1/2 inch of unidentified stuff is sort of like concrete, but porous and softer. Where it got wet near the toilet, it is crumbling. I'm guessing it is some type of leveling mix? So far, I've only hacked it out over a small area near the toilet flange where it was wet. Where it didn't get wet, it's much harder to get out. I've hacked at it with a chisel, but it's very slow going. I think I want to get it all out to get down to the bare slab, but I'm not sure exactly what I'm dealing with and how best to go about it. I've included a couple photos, but it's pretty hard to see the stuff in them.

1) What do you think the stuff is and how best to get it out? Any idea if it might be hazardous?
2) Once I get it out, what is the best way to put a new tile floor over the concrete slab. I think I'll need a total thickness of about 1 inch (including the tile) for the floor to match the level of the floor outside the bathroom.

Thanks for any tips you can provide.


Thank you for your question Paul,

   That sounds like quite the ensamble of materials that made up your floor. The Pergo in the middle blows my mind as that is a floating floor...why go over it? Anyway if your down to the suspect layer of cement you are ready to get things done from there. What I suspect you are currently facing with the 1/2" layer is "light weight contrete" or Gypcrete (trade name) it is a material that is typically used in Commercial application like long hallways/lobbys/mechanical rooms that sort of thing. It can also be scaled down to a single room. If they treated the surface with a hardener (acid primer) then things can get quite hard. For me when I had been facing this kind of material I would employ a chipping hammer (I ended up buying my own years ago) and wet the cement with the goal of softening the material and holding down airborn dust. The electric hammer usually made short work of it. You can rent one for the day for about $45.00 and you would think that a chisel would come with it but it doesn't so you will need to rent one of those, get one with at least a 2" blade...3" would be better as you won't dig in to the slab layer below as much. Gypcrete does not contain any hazardous material but the dust can irritate your sinus's and eyes so another reason to wet the floor (the material can hold a lot of water as it will soak it up) so goggles and gloves and face mask anyway. It's a common sense kind of thing Paul when doing any kind of demolition. Now for you second question....the easiest and quickest way to build back your floor is to simply purchase some "Wonderboard" (brand name) cement board and just laminate two layers together right over the cement slab. You install it with a Latex modified thinset combed out just like laying tile one layer at at time. You will need to do a full spread on the slab then a skim coat on the back of the board so that you are putting down each layer wet to wet...follow me? You can employ either a 1/4" square notch trowel or a 3/8" V-notch trowel for applying the thinset/cement board sandwich. This will quickly give you probably a bit "more" than 1" perhaps 1 1/8" so if that is too high they make 3/8" thick Wonderboard which will account for the two layers of thinset as the setting adhesive thickness. I have long favored Wonderboard because of it's rigid construct but there are many other manufacturers out there to choose from so whatever is in your area will be fine. There is no need for mechanical attachment like shotpins or tap-cons the thinset will do nicely just keep things combed out uniformly so that each layer will settle in nice and flat, I always walked on the board after I set it in place to get it pushed down good into the setting material. Once you have both layers down let set for 24 hours and your good to go with the new floor. Ok Paul I hope this helps you with your project...feel free to return anytime should something new arise just come on back....

Perry V.

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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...

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