Patching internal sand / cement plaster

[ran1]

Can someone please give advice on how best to patch sand and cement internal render under a problem (leaky) window in my 1940's semi?

I think I have sorted the leak bout was going to add waterproofer or sbr to the mix anyway.

The overall depth is approx 12mm.

Will I require 2 backing coats before a final skim of multi finish?

I'm aware that the backing coat must be scratched before applying the second (float) coat. But do i need to scratch the

float coat ready to accept the finish skim?

Timing and bonding advice between coats would be appreciated.

Thanks all

 

[keithuk]

Can someone please give advice on how best to patch sand and cement internal render under a problem (leaky) window in my 1940's semi?

I think I have sorted the leak bout was going to add waterproofer or sbr to the mix anyway.

The overall depth is approx 12mm.

Will I require 2 backing coats before a final skim of multi finish?

I'm aware that the backing coat must be scratched before applying the second (float) coat. But do i need to scratch the

float coat ready to accept the finish skim?

Timing and bonding advice between coats would be appreciated.

Thanks all

Do both s/c in the same day , use washed plastering sand and as you have said with waterproofing additive is good ,set day or 2 after , best of luck with it

 

[ran1]

Thanks Keithuk. When you say "set" does that mean multifinish (skim)? And do I score before I skim....Thanks for the help!

 

[lucius]

Just score lightly mate with a nail banged through your float about 5mill

 

[ran1]

OK thanks for the advice lucius

 

[keithuk]

Thanks Keithuk. When you say "set" does that mean multifinish (skim)? And do I score before I skim....Thanks for the help!

Yes mate best of luck with it