Liftting Tiles with electric underfloor heating...

[timhuetson]

Good Afternoon,

I am having problems with my bathroom floor.

Last year I completely renovated my house and decided to put an underfloor heating system in the upstairs bathroom, which is working fine apart from issues with the grout cracking and the tiles lifting in the heavy footfall area around the door.

The floor is made up of: floor boards, marine grade ply which is stuck down with no more nails, self - levelling compound in which the electrical underfloor heating is set in, then the tiles.

When we laid the ply we didn't nail it down - would this make the floor flex when it heats up therefore giving me the issues that I'm having?

It is also creaking under foot obviously with the movement.

What should I do - I cannot afford to lift all the tiles. Should I lift the offending tiles and see what is going on underneath, will these come up easy?

Please see picture below which highlights the issue, this isn't just happening in one place but several. (I have more pics if needed).

Please note I am not in the trade so need as much help as I can get!!



Thanks,

Tim.

 

[Gazzer]

Yep you should have screwed it, primed the back and sides with SBR.

 

[Gazzer]

How thick was the ply ?

 

[Ian]

As above. How thick was the ply?

 

[kilty55]

you will need to lift all the tiles imo,the ply should have been screwed down also how thick was the ply please,thanks

 

[timhuetson]

How thick was the ply ?

Thanks for the quick reply;

Thinking back I believe it was only quite thin 3mm -5mm, is there anything I can do?

 

[Ian]

I'm afraid there is no other option other than, to start again, sorry.

 

[timhuetson]

you will need to lift all the tiles imo,the ply should have been screwed down also how thick was the ply please,thanks

Once I have lifted the tiles will I be able to screw through the self levelling compound in between the cabling for the underfloor heating?

 

[Gazzer]

Deffo no hope. Minimum ply 15mm WBP .

 

[kilty55]

no i am afraid not

not only is the ply fixed incorrectly but its the wrong thickness,you wont sort this unless you remove everything

sorry not what you wanted to hear

 

[timhuetson]

Deffo no hope. Minimum ply 15mm WBP .

Sir Ramic, I'm really looking for advise. Are you saying that I will have to lift even the selfleveling compund and the tiles or just lift the tiles and screw down?

That would be a huge job and cost quite a lot... Surely there must be a fix?

 

[Ian]

So are you going to lift all the tiles and use them again?

 

[Gazzer]

A fix or a chance ?
Only way to fix is to use correct materials and correct methods. So the correct way would be redo the job.

The chance ? would be give your way a try....it may work or may not. You really cant expect professional tilers to advise any other way than the correct way as I hope no one on here would have used 4mm ply glued with "No nails" !

 

[timhuetson]

So are you going to lift all the tiles and use them again?

I was going to try to lift the tiles in the offending area and then screw the ply down and reuse them.. if possible.

 

[kilty55]

is it the ply thats at fault or is this creaking the sub floor not being prepared either and has movement though?

either way screwing through levelling compound will not solve it imo and re using the tiles is another issue

there is no quick fix its been installed incorrectly

 

[timhuetson]

A fix or a chance ?
Only way to fix is to use correct materials and correct methods. So the correct way would be redo the job.

The chance ? would be give your way a try....it may work or may not. You really cant expect professional tilers to advise any other way than the correct way as I hope no one on here would have used 4mm ply glued with "No nails" !

I suppose its worth a chance and then if it doesn't work do a proper job.

I was new to laying floors etc, so this has been a learning curve and I should of sought advice in the first place.


But thanks for the advise its much appreciated, have you seen this happen before?

 

[Ian]

The thing is, if you are going to attemp to fix this by screwing the ply down (which I don't advise), you are going to need to screw the whole lot down not just the affected area. Give it a go by all means but, it is very doubtful that it will fix the issue long term.

 

[timhuetson]

is it the ply thats at fault or is this creaking the sub floor not being prepared either and has movement though?

either way screwing through levelling compound will not solve it imo and re using the tiles is another issue

there is no quick fix its been installed incorrectly

I do think its the ply and glue thats at fault... its flexing under the pressures and when getting warm etc.

Thanks for your advice.

 

[Gazzer]

I suppose its worth a chance and then if it doesn't work do a proper job.

I was new to laying floors etc, so this has been a learning curve and I should of sought advice in the first place.


But thanks for the advise its much appreciated, have you seen this happen before?

You may as well give it a try as it wont cost much. if it fails again then you know what to do.

 

[swanman]

I would start again

Use hardi backer as well

Good LUCK