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N. Thornton
 
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Default Damp under upstairs window. Porous sill?

Phil Addison wrote in message . ..

After getting thoroughly confused about whether to point and render,
with what mix, or to just point then go straight for browning, or
bonding, onto the brickwork, I have opted to point and render, so have
bought a bag of lime, one of Ordinary Portland Cement, and a couple of
bags of sand. I propose to mix 1:1:6 by volume (OPC:Lime:Sand) with no
waterproof additive.

I'll use this to point and then go straight on to a render scratch coat,
and finish off next day (or maybe the one after) with a skim of Thistle
Finish if I can find some, otherwise multi-finish. The standard bags of
lime and cement are, I am pretty sure, far more than i need for this 4x2
patch, though it is quite deep in places, up to 1.5".

Does that sound OK? That's tomorrow's plan, so please shout quick if it
needs modifying!


sounds like an excellent set of choices. The only thing I'm uncertain
about is what mix would be best for the internal rendering. I've asked
people here about it, on ukdiy, so will see what they say. Last time I
did something similar I put a thin layer of 1:1:6 on then filled the
rest in with 1:1:4. That way the bricks see soft mortar so they dont
get admaged later, and you still get a lot of the wall and surface
strength of a stronger mix. And I believe the lime content has limited
crack healing ability.

BTW the pointing can be done extremely quickly by putting on a glove
and just smearing handfuls of mortar along and into the joints. Since
its about to be rendered over it doesnt matter a monkeys what it looks
like.


Further sill treatment with w/p paint will come later.

I'll update the photos with the result if I'm not too ashamed of it - my
plastering is still in the learning phase!


Lol, I've got that to look forward to here too G'luck.


Regards, NT