Standard non-flex adhesive onto SLC? - Tile Advice

[Martyn Leeds]

Hi, Just a quick question to double check if I'm thinking right on this one. Concrete floor + Ceramic tiles. Thought I could get costs down by using a standard non-flex adhesive. I've levelled some areas using a non-flex SLC, Mapei Ultraplan ECO. So can I still go with a non-flex adhesive? or now that its on to a SLC base, do I need a flexible adhesive? Thanks in advance.. PS. I wish my Return button worked.

 

[Martyn Leeds]

??

 

[charlie1]

Non flexi adhesive will be fine mate

 

[Martyn Leeds]

Cool fanks. Thought so. Just started to doubt myself tho!

 

[Brian the Tile]

go ahead no problem

 

[DHTiling]

why did you think you needed flexi ..?

 

[Sean SML Tiling]

Does standard adhesive have limited movement? For example 1mm and flexible allows 3 mm.

 

[SJPurdy]

Does standard adhesive have limited movement? For example 1mm and flexible allows 3 mm.

It is best to think of the so called flex adhesives as having a lot more sticking power than the non modified (non-flex) adhesives. Neither of them will stretch, bend, deform, or whatever by any amount that you will be able to see without a sensitive micro-meter. If you took two pieces of ply and stuck a tile to each, one with a standard C1 adhesive and the other with a modified C2 "flex" adhesive. Then if you tried to bend the pieces of ply the unmodified adhesive would let go of the tile before the modified "more sticky" adhesive does. The next class up of adhesives are termed S1 (deformable) and S2 (highly deformable). An example of S2 is BAL flex which when set is still rubber like and can be deformed when subject to stress, and it will return to its original form when the stress is removed - something that you can easily see but it is still by a small amount (I guess ~1mm in a tiling situation) and will be difficult to measure without specialist tools. Back to the original post if the tiles are simple ceramic then normal addy is ok but if they are more vitrified then i'd use the more sticky modified adhesive.

 

[Sean SML Tiling]

So basically if you tiled a new build house floor straight onto concrete base would you use flexible due to the foundations moving?

 

[Martyn Leeds]

why did you think you needed flexi ..?

Just wondered due to it being on top of the SLC. Its a while since I've even used a non-flex adhesive. Not very often you get concrete floors & ceramics, without UFH and the like

 

[DHTiling]

Most none flex adhesives are slightly modified anyway , this is to bond to porcelain..