mixed substrate floor

[jay]

interesting:8:

if the chasing only removes portion of the concrete and doesnt cut all the way through then you fill with concrete or render wouldnt the cracks that apear when dry only be shrinkage creacks from drying out quick there for a normal c1 adh should be able to cope

 

[DHTiling]

interesting:8:

if the chasing only removes portion of the concrete and doesnt cut all the way through then you fill with concrete or render wouldnt the cracks that apear when dry only be shrinkage creacks from drying out quick there for a normal c1 adh should be able to cope

But the pipes are heat/hot...?.. So forced expansion..

 

[jay]

thanks Dave take it you dont lag (insulate black foam linning) hot water pipes in concrete over there my mistake but ive learnt something :8:

 

[DHTiling]

Yes jay... some do..

but my overkill on the floor maybe.. but as a method to get straight on with it for misstiler, then an uncoupler would work and no infill drying times..

 

[Time's Ran Out]

Uncoupling was my thought - but are you suggesting just over the plywood areas with an overlap onto the concrete (my choice) - or uncoupling the whole floor area.
Certainly agree that by filling the chases with another mix would cause shrinkage.

 

[peckers]

In the past when this situation has arrived as long as the ply over the pipes area is firm and solid what i have done is used the schutler kerdi mat to bridge over the top of the ply and over the screeded area by 100mm each side. Im not saying it is the perfect solution but i have done this many times and havent had a problem. I always use single part flexible in this situation for the entire floor.

 

[MTiler]

Cheers for all the replies.
Putting Ditra over the whole floor (obviously securing the ply) did cross my mind but wasnt 100% sure that was the best option.

missyT

 

[DHTiling]

Uncoupling was my thought - but are you suggesting just over the plywood areas with an overlap onto the concrete (my choice) - or uncoupling the whole floor area.
Certainly agree that by filling the chases with another mix would cause shrinkage.

Both ways john... both work and each job needs to be taken at their own face value..

i.e. what are the risks..

I have seen a few floor jobs where a crack appears in a line and on closer inspection it is in a break in the floor( like patching in etc) or cracks.

But the main thing here is the radiator pipes( heat) ...if the plywood sections are narrow and well fixed then even a crack isolator would suffice..

 

[MTiler]

Both ways john... both work and each job needs to be taken at their own face value..

i.e. what are the risks..

I have seen a few floor jobs where a crack appers in a line and on closer inspection it is in a break in the floor( like patching in etc) or cracks.

But the main thing here is the radiator pipes( heat) ...if the plywood sections are narrow and well fixed then even a crack isolator would suffice..

crack isolator?

 

[DHTiling]

crack isolator?

Kerdi or dural wp.. or pci pecilastic , all are crack isolators as well.