Flooring tiles - grout is cracking

[jasperpie]

after renovating my bathroom i replaced the floor. The floor is even and level and i have tiled this with floor tiles which must be 2ftx2ft and they are really heavy.

I have now found that the grout has cracked and there seems to be movement between the tiles (only minor). I cant see how the tiles can have movement because of the weight of them alone.

Could it have been poor speading of my adhesive that has caused this issue. I cant recall the brand of the adhesive but it was not cheap (it wasnt pre-mixed either - so i may have mixed it wrong)

im normally pretty good with this sort of thing, do you think it will be a simple job of lift, clean and re-lay.??

any advice is welcome

thanx

 

[bathstyle]

Explain how you prepared the floor before tiling

 

[jasperpie]

the old flooring was taken out and exterior grade ply was laid (i think thats what it was called).

I then pva'd the flooring in prep for the adhesive ensuring all clean etc. I then simply spead the adhesive using a large notched trowel - dumped the tiles on and used a rubber mallet to get them squared off and level.

 

[bathstyle]

Despite it not being ideal to have PVA'd the floor it sounds like the tiles have been well stuck down.

There is movement in the floor somewhere and the only way you can sort it out is by ripping up and re doing the floor, possibly by using a thicker ply, possibly by overboarding, I suggest popping into a local tile shop and getting some professional adhesive and before you tile give the technical department a call.

 

[Richard C]

Need to know more about what was done; how thick was the ply, how was it laid out (joints, noggins etc) & how/where was it fixed down? What condition were the joists in? Where are the cracks, do they align with any joins? What make/type of tile adhesive/grout did you use?

Good trade quality products are very reliable but if the floor is flexing to any degree, it will crack & even the most expensive products will fail.

As stated, generally not a good idea to PVA before tiling & never in wet areas.

 

[jefoss]

sounds like you never used flexi adh to me.



oh yeah and run away from pva

 

[joe-90]

It sounds to me like the ply wasn't secured properly and had some bounce in it.

 

[jasperpie]

the ply was laid on top of the joists and any pieces that butted together were done so on the actual joist.

this has been screwed directly into the joists and as far as I can tell its pretty tight. The joists are in mint condition.

If i put my long spirit on the floor and put weight on the floor, i cant se any noticable gap.

I cant recal the brand of adhesive but i know it wasnt "wickes/focus etc" own brand, i do remember it being recommended by a lad who renovate houses - he was doing one up in my street but mas since moved on. It wasnt cheap though - my wallet remembers that much.

One thing i never mentioned is that I have taken up a couple of tiles and the adhesive can be chiseled off the tile and floor relatively easily.

I think it might be movement in the floor as posted earlier or (moment of clarity) - could it be that the adhesive was mixed poorly and is deteriorating under the weight of traffic. I'm hoping not though cos my wall tiles overlap my floor tiles. lol. Hindsight is useless. haha.

ill do some more poking round when i finish and post later.

thanks again for all your info

 

[bathstyle]

Sounds like too much water in the mix and the floor is bouncing too.

I would be very tempted to fit a high quality vinyl floor like Amtico or Karndean.

 

[Richard C]

the ply was laid on top of the joists and any pieces that butted together were done so on the actual joist.

How thick is the ply base?

this has been screwed directly into the joists and as far as I can tell its pretty tight. The joists are in mint condition.

How close are the screws?

If i put my long spirit on the floor and put weight on the floor, i cant se any noticable gap.

It takes very little flexing in the floor to cause failure, particularly if the wrong adhesive/grout is used.

I cant recal the brand of adhesive but i know it wasnt "wickes/focus etc" own brand, i do remember it being recommended by a lad who renovate houses - he was doing one up in my street but mas since moved on. It wasnt cheap though - my wallet remembers that much.

I thought my memory was bad enough , can you really not remember anything about it?

One thing i never mentioned is that I have taken up a couple of tiles and the adhesive can be chiseled off the tile and floor relatively easily.

That’s not good; a decent powdered floor adhesive can be the devil to remove once it’s set!

I think it might be movement in the floor as posted earlier or (moment of clarity) - could it be that the adhesive was mixed poorly and is deteriorating under the weight of traffic.

Was it a cement powder adhesive you mixed yourself or redi-mix in a tub? If a powdered adhesive, it could be you mixed it too dry & that may account for the poor adhesion but it would also be difficult to spread & use; I assume you laid the tiles on a continuous, notched bed of adhesive?

I'm hoping not though cos my wall tiles overlap my floor tiles. lol.

Given what you’ve said, I think you should prepare yourself for the worst scenario; if the adhesion is failing over large area, it’s almost certain the tiles will have to come up. If the adhesive bond is that poor you may get away with relatively few breakages.

Hindsight is useless. haha.

Good research, preparation & using the right materials works much better

 

[bathstyle]

What size joists do you have??

 

[joe-90]

Use a flexible acrylic grout. There can't be that much movement or the tiles would crack.

 

[jasperpie]

im not much help with this at the mo - didnt have much chance to look at the floor when i finished work this morning.

im off work tomorrow so i will take the tiles up - get as much info as humanly possible and post back.

Might as well start fresh, and begin with sound advise.

cant believe ihave managed to tile all the walls, laid wood flooring through out downstairs - move all plumbing, move walls and doors etc. and some how i have managed to cock up only a dozen floor tiles. (yes the bathroom is that small - lol)

ill post tomorrow - with answers to questions and what i find.

ill even dig through the garage to find the adhesive i used (its a while since i tiled it) but the missus complains it aint finished