Expansion joints

[Sean SML Tiling]

Hi guys need a little advice please on a job I viewed today. Its a 60m floor 1 room but 45m has ufh and between the new substrate and the existing floor there is a 2/3mm gap. Customer doesnt want to go to the expense of ditra but also knows the effect it could have on the tiles if theres movement. I was thinking if there was an expansion joint directly between the 2 substrates could that reduce complications of movement? All suggestions appreciated

Thanks
Sean.

 

[The Legend; Phil Hobson RIP]

Hi Sean, BS 5385 says field tiles should not exceed 10 meters in any direction, but I tend to work on 8 meters or less, perimeter joints as well.

I would definatley put a joint between the two substrates. Hope this helps.

 

[Sean SML Tiling]

I was thinking splitting the 2 floors anyway pkus splitting the 36m directly in half again. The floor is 12m x 3m ufh section other floor 16m no ufh. So if I chose expansion on the join I could get away with no ditra?

 

[The Legend; Phil Hobson RIP]

I was thinking splitting the 2 floors anyway pkus splitting the 36m directly in half again. The floor is 12m x 3m ufh section other floor 16m no ufh. So if I chose expansion on the join I could get away with no ditra?

What type of tile are you using Sean?

 

[Sean SML Tiling]

Its a 4 tile pattern travertine affect porcelain 10mm thick.

 

[The Legend; Phil Hobson RIP]

I would feel safer using Ditra, but if the customer doesn't want the extra expense, you can only try to explain, then it's their choice. Good luck.

 

[Sean SML Tiling]

Thanks phil. Appreciate the help

 

[AliGage]

Not stating it should or shouldn't. But in a 12x3 metre room, with tiles laid opus, would an expansion joint really be necessary? Opinions.

 

[The Legend; Phil Hobson RIP]

Not stating it should or shouldn't. But in a 12x3 metre room, with tiles laid opus, would an expansion joint really be necessary? Opinions.

Ali 36m2 is this one room? if there are doorways I would put expansion joints in them, also perimeter joints.

 

[Sean SML Tiling]

Its actually 41m of 1 floor with ufh no door ways. Then joins a 16m kitchen no ufh and then into a utility 10m with 1 door way.

 

[DHTiling]

Typically a heated tiled floor should be no bigger than say 8x5 mtrs , an area of 40 mtrs..

I do take it is wet UHF ..?

 

[Sean SML Tiling]

Yea 41m of anhydrite piped ufh.

 

[DHTiling]

Yea 41m of anhydrite piped ufh.

Heated calcium sulfate floor screeds, movement joints should be detailed:
 Over structural joints in the underlying construction. These movement joints through the screed and tile bed should coincide with and be designed to accommodate the same movement of the underlying structural joints.
 At perimeters of floors where the screed abuts walls and upstands.
 As a movement joint through both the screed and tile bed dividing the tiling into
areas not greater than 40sqm. The areas bounded by movement joints should be
square to rectangular with the width to length ratio not exceeding 5 to 8.
 As movement joints at significant changes of width of the screed surface and in
doorways.
 As a bay joint isolating areas of screed with separately controlled heating circuits.
 At doorway thresholds between separate areas of use.
 At junctions between heated and unheated sections of the screed.

 

[Sean SML Tiling]

Have you ever used nicobond gypsum adhesive?

 

[DHTiling]

Nah ...