SBR or PVA

[Kanon1]

I need to re-tile my front door step after the tiles came away during the winter. The mix under the tiles was damp and crumbling away and so I have removed the tiles and the bedding mix and taken it back to some bricks and concrete. I need to reform the step to tile which means increasing the height by about 2 inches and repairing the front step facing. My plan was to use a PVA slurry and then concrete on top but I'm concerned about bonding using PVA in a damp area and wanted to know if using SBR mixed in the with the concrete would be ok to tile on top of. I understand that SBR is a water-proofer and wasn't sure if tile adhesive would stick to concrete that contained a water proofer (SBR).

Thanks in advance for any advice.
Regards,
Mark

 

[J K Tiling Cornwall]

Always SBR over PVA. Tiles will stick fine with a good S1 adhesive. You can always slurry coat the step first. Dilute SBR 50:50 and mix with adhesive. Brush on and leave to dry.