Opinions on a floor prep - Tile Advice

[mike1979]

A customer took up old tiles ready for me to come in and discovered a piece of 5 mm ply under the floor it's only about a foot wide and runs about 3 metres so I took up the ply and underneath was a set of radiator pipes and the ply sat on two pieces of 2x2 so as the rest of the floor is concrete I was going to take the ply of and replace it with a cement board also the 2x2 is free standing in the gully do you think if I just replaced the ply for cement board it wouldn't crack the floor was fine before so I presume it would be ok

 

[Spud]

It's quite common, I would be tempted to put desotape over the pipes and screed over them

 

[mike1979]

Ye that's what I wanted to do but they wouldn't go for it worried about the pipes bursting which the chances are they won't but I can't convince them to fill it in

 

[Spud]

How wide is the pipe tray 3 m long x 55mm deep x ?

 

[thompsonbrown]

If there worried about the pipes cover them with a waterproof barrier, Denso tape is good.

 

[On one]

Ye that's what I wanted to do but they wouldn't go for it worried about the pipes bursting which the chances are they won't but I can't convince them to fill it in

So they are more bothered about the unlikely chance of their pipes bursting than the more likely chance that their floor tiles will crack due to movement in the floor?
Denso tape the pipes and screed over using rapid setting cement in the screed and jobs a good un!