polished porcelain problems?

[Stewart]

As I said I'm lost, because I installed over a hundred floors with heatmats last year alone, and haven't had this problem. All my heated floor installs have a decoupler with them and the two floors I had to replace last year due to damage by other trades were an absolute $€^% to lift. I have come across a few L cuts fracturing, but I put that down to the tile having hair line cracks at time of fixing.

 

[deankyall]

that was just that job,they also had faults on the valves so it was running without stats full blast,anway as i said yesterday another tiler sent me a video yesterday and tiles came up clean and took him 2 hrs to take adhesive up,underfloor heating on that too,the adhesive bonds to the floor like sh.. to a blanket,but not to porcelain,dave have you ever taken one up?

 

[deankyall]

stewart would you use ditra on a new screeded floor with underfloor heating then? also which addy do you use?

 

[deankyall]

def not,always mix correctly,try a test would be intersting to see if porcelain comes up clean although you have to wait a bit maybe,also i think its when combined with underfloor heating

 

[doug boardley]

I can only say that in 30 years tiling I can't recall any instance where I've had a floor tile (most porcs) delaminate or crack.

 

[DHTiling]

i have tested this back skimming it makes no difference ,we had reps and the tile federation, all had no problems at all about the fixing method , with the right notch trowel and the adhesive correctly mixed it acheives the correct coverage, actually they take a sample away to test to make sure you have correctly mix,listen most work is porcelain nowadays,and ive done loads of it but if say someone drills something wrong and you have to take a tile off to repair,it will come of clean. in fact i was talking to aplumber on site last week and they told me they had chipped a tile and went to hammer it off and the whole tile came off with no adhesive on the tile ,now i dont kow who did it ,but this was a porcelain wall tile.

Dean.. i asked before mate.. who is the Tile federation.. Do you mean The tile Association..? TTA..

 

[Spud]

i do understand what you mean Dean but you need to hit the porcelain tile which a club hammer and a chisel to remove it from the bed ,if you do that the tile will come up clean without much adhesive stuck to the back, i put it down to the bond between the screed and the adhesive bed is stronger than the bond between the adhesive and the tile, if you are concerned add bonding agent in to your adhesive this will bring the adhesive up to s2 rating and you wont have the problem anymore

 

[Stewart]

stewart would you use ditra on a new screeded floor with underfloor heating then? also which addy do you use?

Yes, I use a decoupler with every floor with a heatmat or in-screed heating installed regardless of how new or old the substrate is. I use Nicobond Rapid-Flex addy most of the time and as I've said earlier I haven't had a single failure (touch wood)!

 

[deankyall]

also dave,what im essentially saying is adhesive does not bond to peocelain as much as to ceramic,this is due to the nature of porcelain,and the couple of adhesive companys i spoke to said this too,my questio is if this fragile bond is then combined with the heating,then surely this is gonna cause a problem?

 

[deankyall]

i do understand what you mean Dean but you need to hit the porcelain tile which a club hammer and a chisel to remove it from the bed ,if you do that the tile will come up clean without much adhesive stuck to the back, i put it down to the bond between the screed and the adhesive bed is stronger than the bond between the adhesive and the tile, if you are concerned add bonding agent in to your adhesive this will bring the adhesive up to s2 rating and you wont have the problem anymore

you say s2 rating ??,i actally asked technick,or now called bostik,if i could add a polymore,they said no need,but i think it needs more

 

[deankyall]

Yes, I use a decoupler with every floor with a heatmat or in-screed heating installed regardless of how new or old the substrate is. I use Nicobond Rapid-Flex addy most of the time and as I've said earlier I haven't had a single failure (touch wood)!

i will suggest this the builder of three houses i have coming up,i dont think they will go for it,75m2 in each one,so cost an issue i imagine for them,also the height issue which i know is only about 7mm, but apparantly they are going for a london look ,all flow through,so i will offer them the option.
Thats the trouble with our industry,we know it should be 15mm ply but you try getting the buildr to use it,you turn up and say im sorry but cant tile that unless you use 15mm not 9mm and they look at you like you have 2 heads. i think im going to say unless its used ,i cant garantuee from now on,why should i when the adhesive companies wont? wonder if they'll listen??

 

[Scott]

Doesnt matter if you say you wont guarantee it. If you tile it and it fails your still liable as you are the professional who undertook the job. The only option is to not do it. If i have a customer who doesnt want to pay for the correct prep then i dont do the job. Simples

 

[deankyall]

Doesnt matter if you say you wont guarantee it. If you tile it and it fails your still liable as you are the professional who undertook the job. The only option is to not do it. If i have a customer who doesnt want to pay for the correct prep then i dont do the job. Simples

talked to the local suppliers today,have their own tile fixers,they have now started to use dural matt on all floors with underfloor heating,but they dont fix with flexible tile adhesive as they feel its too rigid ,and if a tile needs changing then it pulls up the mat,they use vinyl flooring adhesive ,which in theory makes sense as it is like silicone when dry ,and they say you cannot get the stuff up if you need to pull a tile,but my question was ,would this void any garauntee? trouble is everyone has different methods and ideas,i asked if they backskim ,they dont,they use round notch and square,which i think makes no difference personally as long as the sticky is wet enough and mixed correctly.

 

[deankyall]

Doesnt matter if you say you wont guarantee it. If you tile it and it fails your still liable as you are the professional who undertook the job. The only option is to not do it. If i have a customer who doesnt want to pay for the correct prep then i dont do the job. Simples

also the customer who is building the houses,will then have to pay another £20 per m2 for matting as well as the extra adhesive cost,they can also phone the adhesive rep who will tell them that a decoupling mat isnt neccessary,thereby making the tiler look stupid,

 

[DHTiling]

also the customer who is building the houses,will then have to pay another £20 per m2 for matting as well as the extra adhesive cost,they can also phone the adhesive rep who will tell them that a decoupling mat isnt neccessary,thereby making the tiler look stupid,

This is where your skills as a pro tiler come in.. SELL the product and why not using it can have serious effects and they only want the job done once.. so it is wise to pay a bit more for peace of mind..

Taking the stress out of a floor is common sense..

 

[deankyall]

This is where your skills as a pro tiler come in.. SELL the product and why not using it can have serious effects and they only want the job done once.. so it is wise to pay a bit more for peace of mind..

Taking the stress out of a floor is common sense..

maybe your right dave but,as you know customers will a lot of times go on price,and there is a chance that someone could tile a floor without a decoupling mat as has been done for many years and there will not be a problem at all,and they will be £200 cheaper than you!! also do you remember when fastflex came out? said you can tile straight on floorboards,this what were up against ,you could tile a bathroom floor with a rubber based 2 part flexi on top of ply and have no worries at all,but if you then price a decoupling mat and someone else dosent,you could end up losing a lot of work,which people cannot afford in this climate

 

[deankyall]

also the job i had in mind is around 220m2, that is prob an extra cost of about £6000 ,do you think that they would go for it ??

 

[DHTiling]

I have never trusted fastflex..

Yes floors have been tiled for year without membranes but floors have not had heating in them for years..

 

[deankyall]

I have never trusted fastflex..

Yes floors have been tiled for year without membranes but floors have not had heating in them for years..

well they have dave ,underfloor heating has been around in various modern forms since the 60s ,wont go back as far as the romans!! but seriously adhesive manafacturers normally never have been recommending a decoupling mat as standard,so what we are saying is that their adhesives arent up to the job that they have been telling us! is that right? i think there should be a standard method statement from all companies stating how and what method should be used with the adhesives ,then the shoulder of burden would not be on the tilers all the time,everyone working together,just a thought.

 

[DHTiling]

LOL.. various forms we could say,, but wet heat systems in the uk built into screeds are getting common now.. so times move on and tiling has to move with it..

 

[DHTiling]

Just some info to think about..

BS5384-4 advises that stresses may develop within the tiling system as a result of movements due to such factors as drying and shrinkage and moisture movements in the background and thermal and moisture changes in the tiling.
These stresses, if not properly controlled,can be sufficient to cause loss of adhesion and bulging or cracking of the tiling..

So worth thinking about when finding a cause for de-bonded tiles and cracked L cuts etc... Stress is a major factor on heated screeds..

 

[deankyall]

LOL.. various forms we could say,, but wet heat systems in the uk built into screeds are getting common now.. so times move on and tiling has to move with it..

which in essence is my point, it hasnt ,even on here the past few nights i hear different ideas and opinions, have the adhesive companies moved on too? in electrical and plumbing trades there is nic and gas safe ,a standard wich must be adhered to, set out by a industry body,in tiling it is a mish mash of different ideas and methods ,so it should be ,"yes with underfloor heating a decoupling mat is always reccommeded "and then there is no difference to pricing between differnt tilers,only on their m2 ,then we all earn more equally too,by the way i think fastflex and topps 2 part adhesive is great stuff ,stick almost anything well,just a basta.. to use.

 

[DHTiling]

The sooner UK tilers are licensed the better IMHO..

 

[deankyall]

also if things have moved on with tiling they should also move on with other trades,screeds, why arent there expansion joints,set in the screed,on most jobs there arent,and i cant see how they work when there is just one on surface,and most customers recoil in horror when you explain the method and look of a shluter joint,the building industry needs really to talk to each other, same as plasterers,mostly useless when it comes to flattening walls nowadays,angle beads round windows always a nightmare

 

[DHTiling]

Knowledge dean.. that is what it comes down to.. screeders just bang it in and leave the rest to the tiler..