UK Tile movement and popping noise over underfloor heating

[tinygillespie]

Hi.

We've had a bathroom installed with electric mat underfloor heating in a new extension. The heated mat was not turned on for a month after the tiles were laid and then the heat was gradually increased by 1 degree a day. The mats are on a timer to reach 25 degrees over a 3 hour period each morning and evening.

As you can see from the attached video, the tiles make a popping noise and seems to move excessively.

As far as I understand it, the visible layers are:

bottom - electric mat
middle - tile adhesive
top - tile (900mm x 900mm)

Both the adhesive and grout used were allegedly flexible. I have no idea what particular brands were used.

Is there any way to resolve the movement issue without ripping everything out? I've seen Fix-A-Floor mentioned in various threads elsewhere and wonder if it's worth giving that a shot first?

Thanks.

TG

 

[Dave]

It looks like the insulation boards are not bonded to the substrate. How were they fixed ?

 

[tinygillespie]

It looks like the insulation boards are not bonded to the substrate. How were they fixed ?

If I understand correctly the insulation boards are actually the bottom layer that we can see and the electric matting is sitting on top of that.

I've found another couple of photos that show the insulation board, but unfortunately we don't know how everything was fixed together.

 

[Dave]

There doesn’t appear to be any fixings in the insulation boards. They should be adhered to the floor with adhesive or the recommended tubed adhesive. Then fixed with screws and washers. Nothing like that appears to be in those pics. Speak to your installer and see what they say. But you definitely have a failed installation there.

 

[Dave]

These type of fixings.

 

[tinygillespie]

Thanks Dave for your responses, that's really helpful.

Unfortunately there were a number of other problems with the installation, done by the builder, so I think we'll be ripping everything out and starting again with another installer.

 

[Dave]

Thanks Dave for your responses, that's really helpful.

Unfortunately there were a number of other problems with the installation, done by the builder, so I think we'll be ripping everything out and starting again with another installer.

Probably a wise decision, let us know how you get on.