To Ditra or not to Ditra??? That is the question

[SteveyJ]

Hi all
Just a quick question - I have a 12 sq/m floor I have to start tiling next week, its an open kitchen diner, which were 2 separate rooms, and the a joiing 4 inch has been knocked down to open it up. The floor of the 2 rooms was in really good shape with no concrete cracks or damage and was done in the 60's, where the wall was left an inch deep recess by 4 inchs where block work was removed so this had been screeded, I put self levelling compound over the whole area yesterday to tile Monday, I'm just now weighing up if I should sheet over the floor with Ditra first or not worry about it, as I said the 2 floors were in real good condition, its just the new screeded area where wall was gets me thinking??? Going down is 600x600 porcelain tiles - so really thought Id see what you guys think???

Thanks Steve

 

[widler]

I wouldnt use it,would not see the point in it.
Mind you i have never used it on anything,and prob never will unless someone specifies it.

 

[bugs183]

Hiya Stevey.
You would certainly need to do something as you have 3 different substrates in the floor, these could all move and is asking for a crack to appear.
I would certainly use it to bridge across the crack, i'd extend it about 300mm past each edge, but there will be a slight height difference on the unDitra'd areas. Smae you didn't ditra over the join and then level the other areas.
If the price of the job allows then yes do it all. It would be overkill, but you would have a one sound floor that you would have nothing to worry about.No probs with height differences.

 

[bugs183]

Your missing out then Wilder if you don't use Ditra, its an amazing product and helps with lots of difficult substrate issues.

 

[widler]

Your missing out then Wilder if you don't use Ditra, its an amazing product and helps with lots of difficult substrate issues.

i don't know mate,never used it,ive done a fair few floors with UFH and normal,on timber,new screeds and old floors,only issue ive ever had was a trav floor,about 75m2,over wet UFH,which was not turned on before tiling,no services to house until after they moved in,so wanted it tiling,it cracked in places and im confident that a bit of plastic matting would not of made a ounce of difference .
every other floor ive done,from stone to ceramics,no problem,its a new thing over here.
im also confident that this chap above won't need it bugs,he has got 2 floors with a four inch gap he has filled,the floor has been down for years,the smae substrate in both rooms it won't be moving much now,if at all,so why the expense prob hundreds of pounds of something he won't need,seems a bit mad to me.
no offence to anyone on here,a few bang on about it,i just see no point in this and many situations

 

[bugs183]

Well it does seem too good to be true, but believe me it's no gimmick, and I check any new item out with suspicion.
The thing is its always an unknown removing walls and bridging them regardless of how long they've been down. The floors could have been held under tension and not can settle with the wall being disturbed. I would certainly use it here.
No offence taken matey!

 

[afright]

I do a few bar floor's for a pub chain was having problems with cracked tiles thru water leakage as they would only put ply down started to use Ditra never looked backed great product,in my opinion if your'e not sure use it ,it does work.

 

[SteveyJ]

Thanks for advice - I never thought about laying it over the old wall recess and then SLC over it!!! DOH!!! Will remember that for future!!!

I'm not worried about either old room floor, just that 4 inch strip and what that could do, I know it was a strong mix and suppose only being an inch deep it shouldnt move as the subfloor below the walls and floors were laid on are all the same?!?!

 

[widler]

I do a few bar floor's for a pub chain was having problems with cracked tiles thru water leakage as they would only put ply down started to use Ditra never looked backed great product,in my opinion if your'e not sure use it ,it does work.

did they still lay ply and then ditra ? if ply gets wet if swells,so if you put dirta over it and the ply swells the ditra will move,how will this stop tiles cracking? im only asking im curious,surly if the ply swells the ditra moves the addy moves and then tiles crack?
im going to have a read up on it,im not sure how a few MM of plastic would stop it,must be some scientific mumbo jumbo reason for it which nasa could explain

 

[bugs183]

Ditra will waterproof the floor to a degree. If you tape the joints it is a tanking system. Even without taping far less moisture will get to the ply so there is far less chance of any issues as apposed to tiling direct to the ply with adhesive.
i do have to explain to chstomers how it works as it does seem a bit mad, but work it certainly does!

 

[afright]

did they still lay ply and then ditra ? if ply gets wet if swells,so if you put dirta over it and the ply swells the ditra will move,how will this stop tiles cracking? im only asking im curious,surly if the ply swells the ditra moves the addy moves and then tiles crack?
im going to have a read up on it,im not sure how a few MM of plastic would stop it,must be some scientific mumbo jumbo reason for it which nasa could explain

Yes they still use ply they will not use hardi-backer I keep telling them but it does waterproof it and so far using the ditra I have not gone back on any of the jobs,I use it as much as possible even on an outside balcony same carpenters plyed it have had no problems
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- - - Updated

 

[widler]

Ok lads, cheers for that, ive never been asked to use it, and never recommended it.
I may give it as a option in the future, but i won't lie when they ask me if ive had any faliures when not using it, so they may not like spending the money, as we know most don't.
Cheers again lads, all the best for christmas and new year
Craig

 

[afright]

All you can do is advise and if they dont want the expense then so be it

 

[bugs183]

As Afright says i advise it and let the customer choose, i always use it for tiling onto wood, and highly recommend it for tiling onto underfloor heating. I've seen too many of the subfloors crack to trust going direct.
Chances are you you won't be asked about it, i've been using it for 20 years (when it was more corrugated), and even now people don't have a clue what it is!!!
If you do use it. Lay it one day then let it dry overnight, even with rapidset. Pulling a tile up to reset can pull the Ditra up ,but this won't happen if you leave it overnight.

 

[afright]

It might be another job to do but once you learned how to lay the ditra it is fairly simple and of course you earn a bit more money on the job and you walk away with piece of mind.