Flooring Tile - Kitchen floor tile question

Hi, i'm getting ready to tile the kitchen, here's what i have so far:

5/8 ext grade plywood above 2x8 joists, 16in spacing and 10 feet long. On top of that is a layer of 3/8 plywood.

The floor is 'sturdy' but has a few 'bumps' in it. I would like to lay down another 1/2 inch plywood before my ditra just to level things out (instead of the self levelling cement stuff). I just stopped and looked at plywood - which one do i get? do I need to pay 50$ a sheet?

Also, Is my idea of slapping down another 1/2 inch ok?

Thanks
G

What kind of tile are you planning to install? Ceramic, porcelain, natural stone?

Builders that use 5/8" plywood as a subfloor should be run out of town! They strive to build to the lowest standards and I have no use for them!:thumbdn: Are you positive that other sheet is 3/8" thick? I wonder why it's there? What kind of flooring did you have?

Installing 1/2" underlayment is a good idea, but what makes you think it'll remove any bumps? If anything adding more layers without fixing the bumps will make said bumps even larger, think about it.

What do you plan to install over the plywood as a tile backer?

Jaz

porcelain tiles 13x13 is what is going down, and Ditra as the underlayment.

There is the 5/8 'floor', then the 3/8 subfloor, on top of that was sheet vinyl, on top of that was 1/4 wood, on top of that was vinyl tile, and on top of that was another layer of sheet vinyl... All gone now except the 5/8 and 3/8.

I am not 100% positive the second layer of wood is 3/8 - but i cut a hole in the floor, and the total was an inch - and by eyeballing it it looks like 3/8.

The bump is more of a high part with a slope (you can't see it - but you can feel it if you walk on it) and its right above a joist. I was going to try and 'fill' it with the thinset - but i'm just about the farthest thing from a pro there is and would probably just make more of a mess. i figured the extra 1/2 inch spread out on a 4x8 sheet would 'mask' the bump, and even the slope.

The subfloor should be within 1/4" in 10 ft. AND 1/16" in 1 ft. in plane. High spots are hard to fix, they have to be lowered some how. I don't understand how you were planning to "fill" a high spot?

Jaz

Does this "high spot" run the length of the room? I could suggest a way to fix it if thats the case but these guys would run me out here on a rail. So....answer the question and we can discuss it.:)

Maybe the term 'high spot' was incorrect... better to be called a low spot - or an uneven 'area'. I tried to take a picture - but it really doesn't show anything.

I guess my question is can it hurt to lay 1/2 or 5/8 plywood on top of my existing subfloor before i put the Ditra down? or should i attempt to rip up the 1st layer of 3/8 that is on the floor and see if that takes care of my 'uneven' area? and build it up from there?

thanks for your time
G

Maybe the term 'high spot' was incorrect... better to be called a low spot - or an uneven 'area'. I tried to take a picture - but it really doesn't show anything.

:wall:

Jeeeeezh! Which is it. A low spot is easy to deal with a high spot is a different story.:rolleyes:

I guess my question is can it hurt to lay 1/2 or 5/8 plywood on top of my existing subfloor before i put the Ditra down?

No it can't hurt but that isn't going to change this HI-LO spot you have, it will only serve to enhance the irregularity.:)

or should i attempt to rip up the 1st layer of 3/8 that is on the floor and see if that takes care of my 'uneven' area? and build it up from there?

Why do you think THAT will fix the uneven area? Before you go taking out something that may be beneficial to you find out if this offending area is high or low and then find out why it is high or low and go from there.:)

Ok, it is in fact a 'valley' (low spot type thing) I just assumed it was high because i could feel it when i put my foot on it.

So, now that i have thoroughly made a right fool out of myself in not knowing the difference between high and low... what do i do about my low spot?

(Clearly i'm not cut out for this and should probably just call someone to install this floor for me.... )

Thanks for putting up with me!
G

You are the very reason this forum exists! You can do this tile job...you just need to be specific when you ask a question. No one here can see what you do, only reply to your description. Now that you've described "a valley" I'm sure Mr. Cline will be delighted to tell you how to correct that! (Won't you, Mr. Cline?)

Connie

OK, so it's a valley right? The low spot is shaped like a dish right? If that is all it is, it should be easy for you to fix.

You need to get a long straight edge maybe 8-10 long and inspect the floor from every angle to see how flat it is. Then analyze your next move.

As far as actually doing the work or not, don't feel bad because most people are NOT able to do the work in a professional manner. Most DIY project however are completed where the HO is happy with the results. Those that don't have the confidence or time simply don't attempt to start and write a check instead.

Jaz

The subfloor should be within 1/4" in 10 ft. AND 1/16" in 1 ft. in plane.

Using the details in Jaz's post, tell us how much this floor is out of plane by. Give specific details.:)

OK that's an easy one. But as Jaz suggested you have to find all of the low spots by using a straightedge. The longer the better. Move around the floor and locate the low spots. You can use a felt marker to sort of outline the low spots that you find so that you can find them again later.

Let's see how serious this before we go any further. How about a picture?:)

Here is a picture of my valley - it measures just under 24 inches long, and (thats a dime at the deepest spot) and around 1/4 inch at its deepest

http://img208.imageshack.us/img208/9470/p2250005mediumip5.th.jpg (http://img208.imageshack.us/my.php?image=p2250005mediumip5.jpg)

Is this the only one in the whole area?:)

Thats it... I checked in the basement and right above it is the intake for the furnace.

The valley runs about 24inches long - and less than 10 inches wide (If i pull my 'straight edge towards me) Other than that, I was bouncing on the floor all over and it seems pretty sturdy! No bounce (nothing fell off the refrigerator).

I had this problem and was able to cut a square out of the plywood, back to the center of a joist on each side. Then I added 2x8x16 blocks between the joists, placed so that all 4 edges of the new plywood rested both on the old joists and the new blocks. Glued and screwed around the perimeter and that worked just fine. Since your depression is over ductwork, that approach probably will be impossible for you.

I assume what you'll need is a leveling compound...To straighten out the dip. These are made by manufacturers of tile adhesive. It works something like this:

Place barriers where necessary to keep the compound where it belongs. Mix the dry ingredients with water, then pour it on the floor. The mixture will level itself out to a certain degree, but use a long flat trowel to help things along. The compound should be cured and ready for tiling within a few hours. Most self-leveling compounds are intended to function at depths no greater than 1 inch.

I'm sure if someone has better advice, they'll be along to let us BOTH know!

(See, I told you Mr. Cline would be back to help...and so did Johnny and Jaz. You just need to explain exactly what you need to know and provide pictures when possible. There are a lot of folks coming here with questions, and many of them are the SAME questions.

Mix up some portland cement floor patch, plop it in the low spot. Smear it around so as to promote contact with the substrate everywhere. Then use a straightedge to drag off the excess and leave it alone until tomorrow.

Self Leveller isn't required for this and its way to expensive for this fix.:)

Perfect! Many thanks all. I will pick up the cement tonight and 'smear' it down tomorrow or Thursday.

Should I still lay down another 1/2 plywood over the cement before my ditra - Just for a nice smooth surface?

I will probably be back here a few times before this project is done!

Should I still lay down another 1/2 plywood over the cement before my ditra - Just for a nice smooth surface?

No Way!!! Not necessary.:)

Ok, I have the floor patch - and will have it down this week. My next question is: Once i put the Ditra down, do I need to stay off the floor? I haven't picked up the tiles yet - and it may not be for a week or so... so should i wait and do the ditra just before the tiles?

Thanks for guiding me through this mess!
G

"They" Say you can install the DITRA and immediately begin tiling after the DITRA is in. I don't agree with that and think it is a bad practice.

In your case you want to install the DITRA then in about a week install the tile while in the interim living on the DITRA. I don't see a problem with that as long as you stay off the DITRA at least over night after it is installed.:)

You can install tile over ditra right away no need to wait. Thats normally what I do when possible. If you wont be getting to the tile for a week or so, Id wait to install the ditra. Its not made to be a finished floor and probably not a good idea to trample all over it for a week or longer. It'll be a pia to clean up before setting the tile also. Install it the day before you get the tile or the same day if you want. It'll go down pretty quick.:)

That's probably the best advice.:)