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Hello there,
I am planning on installing 16″ ceramic floor tiles over the concrete slab floor in several areas of my home. Some sections are covered by linoleum. I have a few questions here.
1). Is is better to remove the lino first prior to putting down the tile?
2). I am replacing a hardwood floor with the tiles in the entry area, and also would like to build up the floor so I don’t have too big a gap under some doors that open over the floor. How thick a layer of thinset can be trowelled on without losing strength or risking cracking?. The concrete floor is in good shape.
Thanks!
Bruce J.
Vancouver, Canada
Replies
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Bruce,
It shouldnt be a prob going directly on the concrete. The only issue would be going over the linoleum. If is comes off then you tile will also. So whether to remove it or not depends on how sure you are that it wont come off once the tile is set. The thickness of thin set, Well I just use a 1/4 knotch trowel and spread it on a small area usiing the flat edge and once it is spread then use the knotch side. Its kind of hard to describe other than when you here a scraping sound then you are just about right. You dont want to see the underlayment in this case the concrete in the bottoms of the knotches. You need enough to feel like your compressing the tile into the thin set. I hope this helps. Also I would reconmmend getting a book by Micheal Byrne on ceramic tile. I hope this helps.
*First of all, I'm not a tile pro, but I've been learning (and observing) a lot about it as I've laid my tile the past weeks (over a plywood subfloor). I found that using thin-set and a 1/4" notch I was not getting good coverage with 14" tiles. (Determined by prying one up and looking at the backside) You should consider using a 1/4" (wide) by 3/8" (deep) notch -- square notches will produce round thin-set lines, so I just use a trowel with a rounded notch. (I swear by the stainless steel trowels made by Barwalt -- a real pleasure to use).In fact the Ultra-Flex 2 thin-set that I use calls for a 3/8" deep notch on 12" and large tile. I believe the modified latex thinsets are designed to actually flex, so it doesn't crack. If you need to add height, why not put a layer of 1/4" Hardibacker down over a layer of thinset, and then your tile over that? (It will be almost exactly 3/4" high) You will get a much more uniform result than trying to trowel on the thinset thick.I use a spray bottle with a fine mist to dampen the hardibacker slightly before I trowel on the thinset, and I wipe the back of each tile with a wet sponge before placing it. You don't want anything wet, but moist is good.
*The suggestion to get Michael Byrne's book Setting Ceramic Tile is an excellent one. If you follow his methods you will have a first class tile job. If you don't you will at least have made an informed choice. You can go directly over the concrete though it is preferable to have an isolation membrane. There are a number of ways to do this. It is possible to build up the floor level using a mud bed or underlayment. I have even seen a tile setter use thinset to build up a floor around electric heat. I don't think that this is recommended but if you read the instructions on the thinset bag it will tell you. Consider the need for space under the doors in your entry for mats to wipe off your feet.
*Crusty im not a pro just a DIYer but I think your right about the 3/8" knotched trowel. But doesnt most of your thinset/ grout have the admixture in it? I know you can buy it already premixed. Good idea about the prewettng the tile it will definately help with the set up time.
*Bruce,some good suggestions here,the best being about Byrne's book---1)The answer is, it depends:If the lino is fully glued down and has shown no signs of loose pockets,it is probably OK to go over it(I have done so many times).If the existing floor covering is the type that is only glued along the perimeter and seams,such as congoleum,then you would want to remove it prior to installing tile.2)Do not try to use thinset as a floor filler for height,use some of the many brands of cement board in various thicknesses that are available,gluing each layer with thinset.Byrne's book will have a good explanation of how to select the proper trowel for your application,but this is basically what it boils down to:You want enough thinset to thoroghly coat the tile for full adhesion,without putting so much down that you have to deal with a mess.The consistency of the thinset mix will play a role here,as well.Certain tile profiles will require a heavier application of mortar to help fill small gaps,others will have flatter backs and need less mortar.I almost always use modified(flexable)thinsets.jw
*Byrne's book is most definitely the way to go if looking for long lasting job and good discussion of alternatives. In a bind I've used thinset (always latex modified) to build up floor but only in thin layers of 1/8" or less. Told a friend of this and he tried short cut and put down 1/2" - after a week he removed it all as never did set up. Randy