Who's got tips for a first time tiler?

[CrazyToad]

Okay, I feel like I should chime in here...

About the subfloor thing, do NOT try and use wood, especially in a basement. Tile and grout cracks when there is movement in the subfloor. When the wood swells and shrinks with the seasons, it will force your tile to go with it, therefore cracking it. Ditra will help eliminate this, and Ditra is designed to take the movement away from the tile, and help avoid breaking. You cannot use hardi-backer, or any other cement underlay on concrete because it needs to be screwed down. If you are going to use an underlay, Ditra is the way to go. it is a better product, and much easier to use. It is actually the only product I will tile with now.

With that said, if your concrete is in good shape (flat, no cracks), you can tile directly on it. There is absolutly nothing wrong with that. If you are worried about adhesion, you can buy a modified thin-set (thin-set with bonding additives) for about $12 a bag. It is good stuf, and you will see how tacky it is right away.

If you decide to use Ditra, make sure that you use a modified thin-set to lay down the Ditra, and an unmodified thin-set to set the tile on it. There is an instruction video on the Schluter Systems website for Ditra.

I hope this answers a few questions for you. Good luck. :rockin:

 

[Cookiebaggs]

Just a comment from the land of poured concrete floors (no basements out here). All of my tile is set directly on cement. As are new construction homes. Maybe it's not troweled quite as smooth as my shiny Milwaukee basement was but me think's you can go directly onto the basement floor.

That's what I did.

I layed a 13 x 13 square area in my basement for the bar. I went right over the concrete with the thinset. After 5 years, I've had no cracking or moisture problems. There was a vapor barrier installed under the concrete before it was poured.

I also put in a tile floor in the basement bathroom on concrete with no problems. It can get cold but that's why I wear slippers and use throw rugs.

I would strongly suggest using a floor leveler. That concrete floor may look level but trust me, it is not. Trying to build up the thinset to raise the tiles in a certain area is a PITA. Much easier to start with a level floor!

 

[CrazyToad]

Sorry, one more thing :cross:

If you are really worried about a vapor barried, you can purchase a liquid vapor barrier at the depot or lowe's. The depot sells stuff called Red Gaurd. It is like slime when you roll it on (just use a paint roller), and it will dry like laytex. You can tile ontop of that too. Use 2 coats. Either way, it is not necessary.

For the wet saw, yes, they can be useful, and you will need one for certain cuts, but for straight cuts and inside corners, a score cutter is so much faster and easier. You can pick one up for $13 on the cheap side. Only use this if your cut edge will be hidden by trim.

 

[bradsul]

Just for completeness I thought I'd post the method that is used here in our cold climate for a basement floor for tile. Most tile companies won't push for this much material because of labour and material costs, but in the higher end construction of which I've been involved this is standard practice. For the record I don't recommend wood on concrete at any time (indeed our local building codes don't allow it, you will want to consult your own no matter what you do).

- 2" extruded insulation (R10) adhered directly to concrete and sealed at the seams with adhesive and tuck tape
- 3/4" T&G floating sub-floor
- * ditra
- * in-floor heating
- tile

* depending on the product these may be reversed

This gives a complete thermal and moisture break from the concrete. If you really want a warm basement, use the R10 on the walls and tuck tape and adhere all those joints as well (including those that join to the floor R10).

This is definitely not the cheapest way but it will give you a floor that will last forever (or at least until the SWMBO gets tired of the colour anyway ).

 

[Bobby_M]

I really wish I had the head room to accomplish that Brad because I think radient heating is awesome. I plan to do this in my family room (only room in the house on a slab) to make it more comfortable in the winter. It's got 2 outside walls and one touching an uninsulated garage (whole other project) and I think it's the answer to the winter chill in there.

 

[cubbies]

Well my floor appears to be level. I am not just using my eyes. I layed a level on it in several different spots and all were perfectly level. Plus, the stuff I am using for the moisture will be applied level, so that should not be a problem. The only possible issues are A) some cracking, which is unlikely because of the product I am using and the age of the house and B)cold floor, which is not a problem, the concrete itself is not even that cold, I cant imagine the tile will be. Essentially this product is a commercial membrane that is sort of like tar that goes between the concrete and the tile. My buddy says they use it in buildings all the time.

 

[homebrewer_99]

Just a comment from the land of poured concrete floors (no basements out here). All of my tile is set directly on cement. As are new construction homes. Maybe it's not troweled quite as smooth as my shiny Milwaukee basement was but me think's you can go directly onto the basement floor...

I've tiled directly to the cement floors also without any problems.

How does one put a vapor barrier (usually plastic sheeting) between concrete and thinset and tile? I'd like to be enlightened even if I am wrong, but at the moment it doesn't make any sense to me.

 

[cubbies]

Well, I havent seen the product yet, but from the way my buddy describes it, it is not a plastic sheeting it is kind of like a tar or a glue that you spread with a flat trowel and let cure overnight.

 

[zoebisch01]

You can thinset to concrete, but if it is a glossy smooth finish you should rough the surface somehow to ensure good adhesion. You won't need the expensive thinset either with the flexative.

 

[user 574]

Still believe everyone's overthinking the moisture issue. I tiled my shower walls with 18" tiles using your basic gray thinset and regular grout. Doesn't get much more damp than that .

 

[ohiobrewtus]

After just reading through this thread I thought I'd chime in. Bradsul is right. The best advice would be to put a subfloor down to ensure a level surface (among other things). But when you DIY there's not always money in the budget to do things like that.

I have tiled directly onto concrete floors before and had no problems after 3 years when I sold the house that I did the work in. I actually had more problems with a burber carpet that I glued directly to a concrete floor than I did with the tile.

 

[bradsul]

Still believe everyone's overthinking the moisture issue. I tiled my shower walls with 18" tiles using your basic gray thinset and regular grout. Doesn't get much more damp than that .

I hope you at least used concrete board behind that. If you ever take that shower apart I suggest wearing a respirator or at least a face mask.

 

[Bobby_M]

Yeah, it's not about the moisture making the thinset fail. It's not water soluable when it's set since it's basically concrete without the aggregate. It's about coming up into you nice new living space and creating mold issues both in the grout and everywhere else. People usually live with the moisture in an unfinished basement. It's a problem when you start hanging drywall and putting furniture in there.

 

[user 574]

I hope you at least used concrete board behind that. If you ever take that shower apart I suggest wearing a respirator or at least a face mask.

Yep on the concrete board. If I have my way it'll never be taken apart but that's assuming SWMBO the interior designer won't get bored with it 5 or so years down the road .

Understand Bobby... That's what I started thinking about after my post. I vaguely remember humidity

 

[CrazyToad]

Installing a wood subfloor on a concrete slab is not needed, and is very expensive when ceramic tile is considered. Just a brief history lesson with tiling in the US, tiles were traditionally installed on a concrete slab. If any of you have those old, white, hexagon mosaic tiles in your bathroom, odds are they are installed on about 4" of concrete. In your situation, I wouldn't really worry about the moisture problem, as thinset and tile will not be damaged by moisture. Mold is an issue, but if you seal properly with a high quality sealer, it won't be a problem. Use this sealer, available at the depot (here).

The biggest problem I would worry about is potential cracking. It is not that big of an issue considering you are installing on a slab, but it is still something to take into consideration. If you are that concerned about it though, use Ditra. It is a great underlay that will separate your tile from your substrate. If your substrate moves, your tile will not, and therefore prevent cracking.

In my professional opinion, feel free to tile directly onto the concrete slab. Use a modified thinset like this. It will bond much stronger than normal thinset.

 

[cubbies]

Yeah, that is the decision I made. We are not going directly onto the concrete, we are using a "membrane" kind of like that flexbond. Except it is more of a mortar kind of consistency, it is kind of hard to explain. Basically you flat trowel it over the whole area and it leaves a very thin layer of material between your mortar and your concrete. My buddy works on floors commercially for a living and he says they do this stuff all the time. It will keep the moisture out and will help against cracking. He said it is not very likely my tiles will crack.

We prepped the area last night. Pulled up the carpet, took off the tack strips, removed the baseboards and spread the membrane. Friday we start laying tile!

 

[CrazyToad]

Yeah, that is the decision I made. We are not going directly onto the concrete, we are using a "membrane" kind of like that flexbond. Except it is more of a mortar kind of consistency, it is kind of hard to explain. Basically you flat trowel it over the whole area and it leaves a very thin layer of material between your mortar and your concrete. My buddy works on floors commercially for a living and he says they do this stuff all the time. It will keep the moisture out and will help against cracking. He said it is not very likely my tiles will crack.

We prepped the area last night. Pulled up the carpet, took off the tack strips, removed the baseboards and spread the membrane. Friday we start laying tile!

Flexbond is mortar. You are talking about a product like Red Guard correct? It is a liquid, kind of looks like slime. When it dries, it will be like a laytex layer on your concrete. Be careful when speading your thinset on that stuff, it can tear. Good luck. I hope everything comes out well for you.

 

[cubbies]

Well, the stuff I used was not flexbond, but I guess it was similar. It is like a mortar. it is dry and you mix it with water and flat trowel it on. When it dries, it looks kind of like cement. I am pretty confident it will all work out. My buddy has been doing this stuff for a while, and he is not worried about it.