Expansion/movement joints - porcelain on a concrete slab - TilersForums.com

[JS1]

I plan to lay a circa 8m x 4m patio using a concrete slab and fixing with tile adhesive. The porcelain tiles will be 1200 x 600 or 900 x 450, I want to use a half bond with the longest edge parallel to the 8m length of the slab. The slab will need at least one expansion/movement joint which will be perpendicular to the 8m edge. I presume that the tiles will need a join that runs along/over the top of any expansion/movement joint and I'm looking for advice on I) how should the tile joint which runs over the expansion/movement joint be finished; is grout okay or do I need another method? ii) any design suggestions about how to plan the tile layout to incorporate an expansion joint.

Thanks
Martin

 

[Phone-a-tiler]

Hi, External expansion is important A silicone joint should be used over any slab expansion or
control joints. Id split the 8mtr length in half to 4mtr and silicone any tile areas finishing against
Edging ie Brickwork.
Mask the area with tape may help if you are new to siliconing.
match the colour when buying the grout

 

[JS1]

Hi, External expansion is important A silicone joint should be used over any slab expansion or
control joints. Id split the 8mtr length in half to 4mtr and silicone any tile areas finishing against
Edging ie Brickwork.
Mask the area with tape may help if you are new to siliconing.
match the colour when buying the grout

Hi Thanks for the response. There won't any fixed boundary to the porcelain patio tiles only loose stone so I presume no need for any 'external expansion' provision? The concrete slab will be reinforced and it may have an expansion joint (to be determined) so my question is about the tile joint over the slab expansion joint. If there isn't a need for an expansion joint in the slab I'm thinking of then using isolator matting and laying the porcelain in halfbond without any expansion joints - the tiled area is circa 4.2 x 8m.

 

[Phone-a-tiler]

Hi Thanks for the response. There won't any fixed boundary to the porcelain patio tiles only loose stone so I presume no need for any 'external expansion' provision? The concrete slab will be reinforced and it may have an expansion joint (to be determined) so my question is about the tile joint over the slab expansion joint. If there isn't a need for an expansion joint in the slab I'm thinking of then using isolator matting and laying the porcelain in halfbond without any expansion joints - the tiled area is circa 4.2 x 8m.

I work in a hot country and external house patios that long tend not to have an expansion in the
concrete so I wouldnt expect to require one in Uk climate. You may need to google the building code just
in case.
The brick pattern is a pain for expansion over a joint. matting should work. If there is no slab joint and you were worried about tile movement you could put a silicone joint through a tile joint following the brick pattern if you can match the grout colour.
If there is no patio edging, the tiles expand off the edge. Our distance externally is 4 mtr
I dont think youd worry about 38oc as I have to.
Make sure you flush the grout edge to keep bugs/ants nesting under the tiles or water freezing.
Use a large notch trowel. Serate the floor and butter the tile for good key. No spot fix

 

[JS1]

I work in a hot country and external house patios that long tend not to have an expansion in the
concrete so I wouldnt expect to require one in Uk climate. You may need to google the building code just
in case.
The brick pattern is a pain for expansion over a joint. matting should work. If there is no slab joint and you were worried about tile movement you could put a silicone joint through a tile joint following the brick pattern if you can match the grout colour.
If there is no patio edging, the tiles expand off the edge. Our distance externally is 4 mtr
I dont think youd worry about 38oc as I have to.
Make sure you flush the grout edge to keep bugs/ants nesting under the tiles or water freezing.
Use a large notch trowel. Serate the floor and butter the tile for good key. No spot fix

Do you have an opinion to share on the laying options of a mortar bed v setting with tile adhesive on a concrete slab? The majority of the UK installers appear to use a mortar bed but Tony McCormack who has created the very useful resource Pavingexpert.com recommends the tile adeisve method for the DIY'er as it easier to get a flat finish if the slad has been laid corrcetly. Our patio is for foot traffic only. Thanks

 

[Phone-a-tiler]

Do you have an opinion to share on the laying options of a mortar bed v setting with tile adhesive on a concrete slab? The majority of the UK installers appear to use a mortar bed but Tony McCormack who has created the very useful resource Pavingexpert.com recommends the tile adeisve method for the DIY'er as it easier to get a flat finish if the slad has been laid corrcetly. Our patio is for foot traffic only. Thanks

Personally for safety, if the slab is flat with slight fall, Id go for adhesive. Theres too many variables with thick bed on a large area ( bonding screed to slab then bonding tile to screed then drying time. if the tiles are non porous, especially large size tiles.
Theres still a place for thick bed but pointless on a finished slab.
Consider using Wedges and clips (good ones). As a professional it took me years to use them as they were considered diy but they are quicker to lay tiles with perfect finish and joint size Just use plenty of glue as mentioned and not too dry. Plenty of grout in the joints to fill voids around tile edges.
Lay tiles shiny side up lol

 

[JS1]

Personally for safety, if the slab is flat with slight fall, Id go for adhesive. Theres too many variables with thick bed on a large area ( bonding screed to slab then bonding tile to screed then drying time. if the tiles are non porous, especially large size tiles.
Theres still a place for thick bed but pointless on a finished slab.
Consider using Wedges and clips (good ones). As a professional it took me years to use them as they were considered diy but they are quicker to lay tiles with perfect finish and joint size Just use plenty of glue as mentioned and not too dry. Plenty of grout in the joints to fill voids around tile edges.
Lay tiles shiny side up lol

Thank you that's very helpful.