New Member
So a few days ago I applied 2 coats of Bostik tanking slurry to a block planter I have built which I want to finish with render but after reading a few more things about rendering tanking slurry I’m now concerned that I’ve done it wrong:

Have I left it too long to render?
I applied the tanking slurry around 3 days ago (I’ve still got more of the wall to do; see pic) but I’ve read in other threads that I need to render it around 24hours after Applying the slurry, not sure if this is right or wrong. If it is it’s now been 3 days and realistically I won’t rendering it until a few days time. Does this mean that the render won’t adhere to the tanking slurry? If so what should I do?

What cement render mix ratio do you recommend?
There is loads of conflicting ratios out there and what they contain, some say Lime and some say SBR needs to be in there which I’m really unsure about, can someone recommend the ratio for the 1st and the 2nd coat?


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New Member
One more question, I will be rendering the top of the wall and won’t be applying any copings to the top. Will this cause any issue with water sitting on the top? Should I appply a slight gradient?