O
Old Mod
Spoke with Mark@Tilemaster about exterior leveller back around January I think. Under certain conditions they will/can advise Levelflex. Namely small areas or areas that aren't too open to the elements. Something to do with SLC being shrinkage compensated and having the potential to swell in wet environments. Bostik used to do a version of their Cempolaytex called Ultra which was guaranteed externally and over drives. Not seen a bag for years tho so maybe there was problems.
Well they still advertise it on their web site Rich, thank you!
Cementone Cempolay Ultra - Ultra fast self leveling compound that you can walk on in just 2 hours!