Waterproofer in scratch...

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spreadz

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I'm reading on here that everyone seems to use Waterproofer in there scratch coat.
I understand it slows and gives a more uniform suction rate for top coating. But i've always been told
(when i started out as plasterers labourer and again when i trained at college) and in turn
practiced once i became a proficient plasterer... Waterproofer in the scratch is a BIG no no!!

On a recent job (rendering over clinker block) i worked alongside another plasterer who swears by waterproofing
in both coats... so against my "better" judgement we used a multi-purpose additive (plas-waterproofing-retarding).
scratch went on fine but when we returned to topcoat he wet the wall down and the water just sat there.
we proceeded to top coat but it just "hung" for hours... ended up coming back off as i didn't want to sit till
midnight to rub up.

my questions are:
1. should waterproofer go in scratch?
2. should a scratch (waterproofer or not) be re-wetted before top coating or is this weather dependant.

any other information or comments also welcome.
 
Through time & experience you will learn how much waterproofer to put in your mix - it depends on the top coat really, that's all I'm telling ya:RpS_thumbup:
 
What you using in the top coat Gibbo??
I put waterproofer (Freeflo) in scratchcoat AND top coat:RpS_thumbup:
 
So... reading through the lines a little, A weaker waterproofer ratio in the scratch just enough to control suction but not enough to have to camp out and wait till midnight to float it up. maybe half what the spec says on the guide lines of the product?? and normal amount in top coat?? if you choose to do so...
go on.... be specific... i dare ya! :rolleyes):rolleyes)
 
no water proofer in your scratch coat,surely you top coat would suck in before you get to the end of the lift.let alone rule and get a float over it
 
Yes, use waterproofer in the first coat and no waterproofer in the second coat. Waterproofer is needed to keep the water from entering the house. But if you also put it in the second coat water might get in between the two coats and get trapped, causing dampness and when if freezes it will expand and make the second coat become boast. Use Sand/cement/lime in the second coat with no waterproofer, this will absorb the water then let it evaporate.
 
Yes, use waterproofer in the first coat and no waterproofer in the second coat. Waterproofer is needed to keep the water from entering the house. But if you also put it in the second coat water might get in between the two coats and get trapped, causing dampness and when if freezes it will expand and make the second coat become boast. Use Sand/cement/lime in the second coat with no waterproofer, this will absorb the water then let it evaporate.

Surely if your saying that, then equally if you only have waterproofer in the scratch then, if water got behind the scratch, it could freeze and do exactly the same as you said above ^

Ah man I ******* hate the building game, you can never get a right answer, its more of a mishmash of random ideas and views, some are quite right, some are vaguely right, some are a load of b*ll***s, and what you have to do, is listen to them all, and make up your mind to what you think is probably alright and hope for the best! contradictions on a ******* daily basis alright, try not to worry about it anymore!

Oh and Waterproofer in the scratch for me, To seal water in the new blocks as waters a wicked insulator, on winter days I do 10:1 ratio to make is proper mental waterproof.
 
Well if you must know you have Integralwaterproofer and waterproofer which are different.The first use on scratch coat to kill suction evenly on your wall and help stopping salts coming througth and forming crystals to stop penetrating damp on your wall.The latter is more of retarder plastersizer giving more time and workability which you would use in warmer weather.Someone correct me if i'm wrong but that' what i got taught.
 
Well if you must know you have Integralwaterproofer and waterproofer which are different.The first use on scratch coat to kill suction evenly on your wall and help stopping salts coming througth and forming crystals to stop penetrating damp on your wall.The latter is more of retarder plastersizer giving more time and workability which you would use in warmer weather.Someone correct me if i'm wrong but that' what i got taught.

You got taught b*ll***s, now ******* stop dragging old threads up for crying out loud. Having said that you're probably not for real anyway but one of the pillocks already on here ******* about as usual.
 
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