Our flooring contractor is laying thinset and tile directly over the bare wood flooring with no cement board.
I’m concerned about this approach: I’m going to be putting my house up for sale and need to make sure it will pass inspection.
Any advice?
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If you have a very stiff subfloor, and there’s nothing to prevent the thinset from adhering, and the contractor uses a good modified thinset, and there’s no moisture on that floor, it might be OK. If the floor isn’t stiff, or there’s peeling paint or other material on the floor, and there’s moisture, as in a bathroom, it’s at the very least not the current best practice.
It’s unlikely to fail an inspection - code requirements are the bare minimum, and I’ve never seen an inspector scrutize a tile installation.
You’ll want to ensure that the surface is solid and even before putting the tile down, but it is an acceptable practice to place thinset and tile direectly over the wood subfloor. The only exception would be in a bathroom, kitchen, laundryroom, or any other areas in which the floor might be frequesntly exposed to water.
It really depends on your floor. When you walk on your floor does it have a little bounce or spring to it? If so, I would recommend apply the 4’x4’ cement board. You will know soon enough… If your grout starts to crack and pop out between the tiles than a substrate was I order.
The best practice is to follow both the thinset and tile manufacturer’s recommended specs. While it may be Ok to directly bond to a subfloor in some instances I always recommend using an underlayment or cement board. This ensures the best finish and levelness of my tile and the expectation of proper curing and bonding of the mortor. Keep in mind: “Moisture is the cause of the breakdown and destruction of most construction insurance claims.” It’s your contractor’s job to protect you against these potential dangers.
It is not the best method, but since you are seling this might do for your purpose. Typicaly make sure subfloor is solid, ring nails, hardy board under tiles so the thinset cures.
You can lay tile over anything. It does not mean that it is done correctly. Is the flooring just a plywood subfloor? I am a firm believer in using a 1/2" backer board and using the screws that are used for the application. You know you have a solid foundation to start from. With the 3’x5’ backerboard and all of the screws, you have a strong base that will help the tile adhere correctly and last a long time.
It can be done but in most cases I would lay down hardi board then apply the tile.
You can lay tile over most anything however the question is should you? I dont recommend tile over hardwood as it will expand and move than crack grout or tiles and is expensive and hard to find tiles to replace after a while. IF you must make sure the wood substrate is solid and secured correctly and you may need to buy 5/16 plywood to make the substrate more sound for install but doing this is just as expensive as using a good cement board so save your self the trouble. IF necessary use bonding membrane over the wood substrate and than install cement board. If you are selling immediately after and want to install it over wood than that is your own conscience and work ethic and that is sad. Do it right the first time!
When tiling over wood I have always used galvanized wire mesh and thinset. In 30 plus years i have never had any issues with tiles cracking or coming loose and i have seen and repaired loose and cracked tiles when they were installed with mastic and cement boards. Make sure the subfloor is solid add screws into the floor joists if you have any concerns then the wire mesh and thinset (use flexbond) to set the tiles, grout, seal and enjoy!
No matter how good the thin set is that you are using, if you are looking for a floor that lasts a lifetime do NOT just set tile or stone over any bare wood. You must use a board of some kind. It can be durock, hardi,or dens shield. The only other way to do it correctly is to put down a paper barrier, then metal lathe and float the floor using deck mud. This is how they used to install all floors before the “boards” came out. Don’t be fooled by any contractor saying it will be ok to set directly over wood. And when using a board make sure they put down thinset first, use screws in ALL the screw dots (dont be cheap) and tape all the seams
You can lay tile on wood if its finished hardwood it will need sanded first and then coated with red guard or a similar product.if its just the subfloor than I would suggest adding a layer of durarock or Hardie backer .also a non coupling membrane wouldn’t hurt but can add a lot of extra expense.
You will not have the strongest and longest lasting bond with this method compared to using backer board. If the tiles were expensive it will be a waste of money and will soon fail in high traffic areas.