de couple for ufh

[triton]

Hi this has probaly been done to death, i have a room 6.5mtrs x 14mtrs with wet ufh ,sand and cement screed that has been down for 4 months and appears to be totaly dry .using 600x600 porceain tiles and was going to install 2 expansion joints along the 14 mtr length do i need to decouple, using flexable adheshive cf2 and grouts.

 

[White Room]

Hi and welcome.....has any expansion joints been put into the screed....

 

[triton]

no but i could install some. because of the zones in the ufh i know exactly were to install

 

[DHTiling]

14 mtrs long is deffo to far without at least 1 movement joint installed within the tiling field.

 

[Ajax123]

A heated screed of that dimension should have contraction joints along its length. It is just outside the maximum aspect ratio of 2:1. It might survive if it has been done exceptional well and has pp fibres in but I would expect a few cracks to appear over time. the maximum bay size for heated sand cement screed should be 6m and maximum bay size 15m2 (nhbc hand book guidelines).

 

[kaharrison9]

I always would use an uncoupling matt on a wet UFH.

Not worth the worry of should i or shouldn't i then what if.

Kev

 

[triton]

thanks for that guys... great help. are all flexable adhesives the same or is one better than another there are some good deals on auction sites for half pallet orders

 

[kaharrison9]

It would be know less than an S1 adhesive for wet UFH with an uncouple membrane