Exterior patio help

[Tiler al]

Hi,I need some advice on a exterior patio I have been asked to tile.I have been tiling for approx 3 & half years & have undertaken a lot of interior floors but not outside.The slab to tile on is approx 15 sq meters & is a rapid set fibre based screed which has been down for 4 months & the tiles are 900/450mm by 20mm thick porcelain.My thought process at the moment is to prime with bal primer & the adhesive to use would be bal flex fibre plus as is semi rapid & allows for up to 20mm depth.I would be using a 15mm round notched trowel & back buttering.My questions to you are would you see this as the correct methods & materials for external & would you use a anti fracture mat or is it not needed.I forgot to add that the screed is very flat & has the correct fall on it.Thank you for any help given,I have been lurking on this forum for a while now & it has been a fantastic help to me with the extensive knowledge given out.

 

[J Sid]

I would be looking at bal flex one
The fibre flex plus is a topps only one I believe, maybe wrong. If it is you know its going to cost you.
But yes prime, and no need for uncoupling imo.

 

[Just Rizzle]

i would cover the area to tile in bal flex bone then with there bal flex adhesive stick down your tiles. see bals web site on there flex bone

 

[J Sid]

Why would you use bal flex one Ray?
And which flex one are you referring to?

 

[hmtiling]

If a membrane is going to be used externally then it should be ditra drain imo. I spec it for all my external work
I'm not sure flex bone is even suitable for external use

 

[Dumbo]

I'm with harry , is nobody concerned about frost lift . Ditra drain 8 is my favoured approach
Just done a patio with adpeds but it is a 25 mm build up approx .

 

[Tile Fix Direct Marketing]

I don't think BAL Flexbone can be used externally, we've just started stocking Kerakoll Green-Pro which can be used outdoors.

 

[J Sid]

Max tile and bed thickness for this product please

 

[Dumbo]

I don't think BAL Flexbone can be used externally, we've just started stocking Kerakoll Green-Pro which can be used outdoors.

But is it a drainage membrane , dural ci can be used outside but it doesn't do the same job as ditra drain 8

 

[Tile Fix Direct Marketing]

But is it a drainage membrane , dural ci can be used outside but it doesn't do the same job as ditra drain 8

No that's true, but if the slab has falls do you need drainage membrane?