Hey Tom, that’s a great thing you’re doing for world vision, it’s also my charity of choice.

Tom I’m installing 12″ by 12″ by 3/8 travertine on my shower and bathroom floor. I’d like to have the thinnest grout line possible which I think you stated is 1/8″. When would I use sanded or unsanded grout for this application? On my shower walls I’m installing the same size tiles but I’m not sure wether they’re going to be the honed travertine as on my floor or polished marble but my same question applies about which grout to use on the walls with 1/8″ spacing.

- Roman

Hello Roman,

Grout joints that are larger than 1/8″ should be filled with sanded grout. That being said, many professionals would say that 1/8″ joint should be receive sanded grout because the grout will want to sag or slump when the joint is much wider than the cement compound. Likewise, joints that are tighter than 1/8″ should be grout with non-sanded grout because the sand is just to bulky to allow enough cement coverage around the sand particles and still bond with the edge of the tile.

That being said, I am glad that you mentioned that might put polished tiles on the floor. It is your home and you can do want you want and contrary to what I said above, I would do the following in my own home.

Install sanded grout in the 1/8″ joints for honed wall tile. For hone floor tile, do the same for consistency. However, if the floor tile is polished, sanded grout really does not look so good so you can use non-sanded grout and do the following.

For 1/8″ grout joint on polished floor tile, you can use non-sanded grout but you need to be concerned with sagging. Joint larger than 1/8″ you would also need to be concerned with cracking. To combat both of these, you need to push the grout deep in the joint with a standard grout float. This will take some extra work and be a little slower. Let it dry a little more than normal before using a damp grout float to scrape and wipe the excess grout off. When doing the final circular grout clean, do not use to much water - just a damp sponge. Too much water will cause the grout to sag into the joint. Lastly, when you are all done (after about 2 hours) you can re-grout any areas that sagged (if any).

This really is not as complicated as I might have described it to be and it is definitely worth it for polished floor tiles.

Best wishes and thank you for supporting the Rock Blog’s World Vision kids!

I am installing travertine in a Versailles pattern in kitchen and butler’s pantry. Due to size of grout lines used a sanded grout, but am not happy with the way it filled holes and pits. It looks incomplete and scarred. Any suggestions would be greatly appreciated.

Thank you,

Rebecca

Hello Rebecca,

That is a common concern from homeowners. I have heard this a few times before. The problem will actually look worse in time if you don’t seal the stone properly because the grout will get much darker and look dirty.

I recommend looking in to a matte finish enhancer/sealer. Let me fist say that you need to do some samples first before proceeding with a full application on your floor. However, I do believe you will be happy with the finish. I suggest that you get it professionally sealed and have a matte glaze enhancer put on the surface. This should not look any different on the stone but it will tone down the grout to the level that you are looking for. It will smooth out the gritty sandy look.

I believe the www.MiracleSealants.com has a good product that you can use or check with your local tile store for a reference.

My very best wishes and let me know if I can help further.

Tom,

I am a commercial interior designer. I think we need a reference book. Is there a book or publication that succinctly provides information on the advantages and disadvantages of each type of stone - plus it’s correct installation method (grout line size, type of grout, sealing, maintenance etc.

Regarding Travertine - what are the disadvantages to using travertine (on the floor in a residence hall lounge - to be precise…) Thank you for your help.

Linda Kress, ASID

Hi Linda,

The Marble Institute of America has all the information guidelines that you needed. Check their bookstore and
consumer resources pages.

Regarding travertine on floors, it is widely used but there are some important considerations. For example, if the travertine is not properly filled, then high heel shoes can literally pop the fill right through the travertine, thus leaving pits randomly throughout the floor. To avoid this, you should specify “travertine which has minimal fill and all holes are adequate filled to avoid damage from foot traffic”.

Joints are important. The tightest reasonable joint should be 1/8″. However, if your tiles are quite large, then 3/16″ is reasonable as well. Grout at this width should be non-sanded and filled flush to surface. Grout and thinset should have a dry-polymer additive to increase strength. There are brands like Merkrete or Laticrete that are well known of strength and quality.

Best wishes!

I’m having 12 x 12 travertine (honed, light beige) installed in the bathroom in the shower and back of tub. I noticed that they are not using spacers between the tiles but have them but up against each other. Is that the standard way of doing it or are they taking the lazy way to install? What is the best way to install to insure that there will not be any leaks later on?

Leta D.

Hello Leta,

For shower walls, stone tile, like travertine, should have a minimum joint of 1/16″. If there is no joint space, the grout will not hold in the joints. For joint that are 1/8″ or smaller, non-sanded grout should be used and thoroughly push into the joint with a grout float. Wider joints require sanded grout.

On a vertical surface, I don’t see how spacers can be avoided because the weight of the tile will cause the tile to sag into the piece below. What you described sounds like a problem to me and I don’t see how the installer can explain to you how grout will be pushed into the seam. Travertine tile usually has a little bevel along the edges. It is not acceptable to grout the bevel only because this grout fall out very soon.

If there is no grout in the seam, water will penetrate and get under the surface. This can cause hazardous mold, discoloring and eventual failure of the tile adhesion. You need a 1/16″ spacer between the tiles.

Best wishes

We recently installed Travertine on the kitchen floor with 1/8″ grout lines. The problem we are experiencing is the grout, in some areas, chips at the top. We thought the grout may have been too thick when we installed. Also, the grout used was unsanded. Do you have any suggestions? - Susan

Hello Susan. If you used grout without sand and the joint width is greater than 1/8″, then that could be part of the problem. Grout shrinks as it dries and the sand is needed to keep the ‘body’ of the grout strong. Actually, sand is always good for grout, but thinner joints just don’t allow enough room for cement and sand; therefore, unsanded grout is used in joints 1/8″ or smaller. There are exceptions to this but I won’t go into that detail here.

Secondly, if the grout was too ‘thick’ as you mentioned, I am assuming that is because there was not enough water mixed in the dry grout. This is most likely the problem and unfortunately created air pressure as your installer tried to push the grout into the joints. This would lift the grout when finished grouting. You will need scrape out the unacceptable or failing grout and simply re-grout with a loose/wet mixture. The good news is that this can be done successfully.

Can travertine be drilled? If so what will I need? I’m going to be applying the travertine to shower walls. Any advise before I start is appreciated. Thanks for your time! - Bob

Hello Bob. Yes, travertine is easy to drill especially if you plan to use an escutcheon that will hide all the rough edges created from the drilling. If you are drilling a hole over 1/2″ diameter, use a diamond core pit. Use one made to cut holes in ceramic tile. These are the best for one time use on travertine because travertine is fairly soft. For holes that are smaller than 1/2″ use a standard masonry bit. Don’t push to hard and let the bit do the work. You might want to have a cup of water need by to dip the bit into it every 15 seconds to keep the bit cool. These will make the bit last longer. If you need to drill a hole that is 1″ or larger you will find that the bit will want to skip out of place if you do not have a template. To make a template, simply get a thin piece of particle board, wood or similar (I have even used a cardboard coaster once). Drill a hole through that first and then hole it in place as you use it for a guide to hold the core bit in place.

I am currently having approx 750 sqft of my home tiled with walnut, honed, chipped and unfilled travertine. It is being installed in a Versailles pattern. After the first day, I have noticed several hollow spots by tapping on each of the tiles. I would say that about half of what has been installed is like this. they are using They are using Mapei Keraflor and I believe they were using something different in the kitchen. Also, the tiles are being butted together in several places. The manufacturer recommends a 1/4 inch grout line. They have also installed the tiles over the existing vinyl sheeting in the kitchen. I was most concerned about the hollow sound as I’ve heard that natural stone must have 100% adhesion or it will fail. This was my original concern until reading several posts on the web including this one. The tile installation company is reputable from what i have gathered and has been around for a while. Do I need to stop everything? What should they be doing differently and will the tile already installed need to come up. I am starting to think that I have made a COSTLY mistake. What do you think? - Michael

Hello Michael,
There are several issues here. First, installing over vinyl in the kitchen is a practice when there is a crawl space under the house.

The vinyl is a good moisture barrier. However, cement board must be screw in over the vinyl to provide adequate tile adhesion. It might sound solid today, but it will not in a year from now as the house expands and contracts. Don’t cross your fingers. Get a warranty for adhesion of the tile at this location.

Secondly, the tile you described should be installed with a 1/4″ grout joint and sanded grout. Perhaps a little tighter if that is your preference, but never butt tight. That is not the correct look for this tile or this pattern. You can find many photos by searching google images, “Versailles pattern stone flooring”. Also, be sure to apply a good sealer to the grout and tile when done or this will be maintenance nightmare.

Lastly, the hollow sounding is usually caused by the installer not using a deep enough trowel. Personally, I recommend a 3/8″ or 1/2″ square notch trowel. Anything less will not provide enough thinset under the stone tile which is required to compensate for irregularity in the subfloor. Also, each corner of the stone tile should be ‘back-buttered’ with a glob of thinset because this is the weakest spot and the most common hollow sounding locations. It is best to flat trowel thinset over the back of the entire stone tile before setting in place. If you floor sounds hollow now, you grout will crack in the near future.

Sorry for the bad news and my very best wishes to you.

In the back buttering of 18″ travertine tile, do you use a notch trowel or flat edge putty knife to fill holes in the backs of the travertine tiles and let dry in installation, Also how thick should thin-set be applied–I am using flexbond fortified thin-set mortar?

Thank you, Ed

Hello Ed,

Excellent questions! It is very important to use a 3/8″ square notch trowel on floor and be sure that the floor is dust free. Using this size notch trowel will allow you to press down on the tile to get it level with the adjacent tile.

You may want to have a wet sponge handy to wipe the floor just before applying the thinset. Use white colored thinset. For the back of the tile, the best procedure is to use the flat side of the trowel and apply a quick paper-thin smooth flat coat on it. Also put a little glob on each corner. This is really the premium way to set the tile but most tile installers do not do this because of the extra time it takes. Doing this will support the corners and reduce the hollow sounding, which is common with travertine.

Best wishes,
Tom Cordova

Hi Tom,

I am getting ready to put travertine on my bathroom floor and shower wall. I have 16? square tiles. I am thinking of cutting some of them to 16 x 8 and 8 x 8 inch pieces for a more interesting look. I would rather put them tight together. Do I need to have a grout line between them, or will this create a sealing problem?

Thanks,

Mike

Hello Mike,

I think your idea sounds like a very nice idea but you need to know that you are embarking on a larger task then you think. First of all, yes, you need to leave a grout joint of 1/8″ because you need to install grout. If you do not install grout, water will seep through and create mold at joints. Also, creating a joint with a multi size pattern actually looks pretty good and give an ‘old-world’ feeling. Tight joints also make it very difficult to avoid noticeable lips between tiles because there is not grout transition.

Secondly, do the math. You want the cut tiles to line up so you must create a joint that is the same width as the blade you use to cut the tiles. For example, Cut a 16″x16″ tile in half. Now you have two tiles that are 16″x 7 15/16″. This means that you need a 1/8″ joint to align them with the 16″x16″ tile. Same goes for cutting them again to smaller sizes. This assumes that your blade is 1/8″ wide, which is typical.

Best Wishes,
Tom Cordova

Can travertine tile be butted up tight with each other and grout applied thus not having any or very little grout showing? Thank you.

Ed

Hello Ed,

The short answer is, “No”. Furthermore, I never recommend butting Travertine tile for several reasons. First, the travertine tiles are never cut perfectly and require a joint in order to maintain a steady module across the floor. Second, you can’t put grout into a joint that does not exist. If you do not open up the joint to 1/16″ minimum the grout will not bond to itself and the tile; therefore, it will fail. Third, it is almost impossible to eliminate lips from tile to tile with butted joints, unless you grind down the floor after installation.

Best wishes,
Tom Cordova

Thanks for responding to question about travertine tile being butted up. Can travertine tiles be laid in a staggering pattern or is it best to lay in the traditional pattern so the grout can have more bonding authority?

Ed

Hello Ed,

It is quite nice to run travertine in a staggering pattern, otherwise known as a ‘running bond’. I highly recommend this look because it adds a bit of customization to an otherwise typical looking ’square pattern’ floor. In this case you would eliminate the first problems I mentioned with butting the tiles, but the other two issues still exist.

Best regards,
Tom Cordova