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lewis

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hi eveyone.. i havent used alot of s/c before but doing some damp proof jobs ,do you do a scratch coat then a float coat then skim??? as im trying to match the s/c up with the original float and set but its so thick that if i build the s/c out to match it it just falls off the wall as it is so thick...also would you skim over this the same day????please help as im very confused!!!!!! :-? :-? :-? :-? :-? :-? :'(
 
Just build up to the thickness in coats , depending how many meters there is  and what the suctions like , so you can scratch coat , then float coat then skim one coat a day, if there is no suction, or you might get away with two coats of s+c in the same day just by leaving it a couple of hours then skim it the next day .
 
Sounds like you're not covering the entire wall and having to work to the plaster line. Are you just plastering the damp treated area? If so put a scratch coat on about 10mm and scarify it. Let it set then fill out the rest with float coat and devil when gone off. I personally would skim the whole wall.
If you're building it out you have to do it in layers.
Bit difficult without seeing it and someone else might have another idea.
 
o.k so i dont really wana be going over 10mm thick without doing it in layers .scratch one day float the next and do i need to leave another day to skim or does it just depend on the wall(suction etc..)if its going off pretty quick skim it if not leave till next day???...you say that you would just skim the whole wall after s/c ??i am not doing the whole wall just the bottom where they done damp treatment..do you skim the whole wall as it is easer than trying to get a really gud join from old to new???
 
Always skim the next day when using s&c , whether you just skim up to or the whole wall depends what been allowed for in the price, skimming the whole wall is the better job but theres a lot more preparation in doing so
 
do you skim the whole wall as it is easer than trying to get a really gud join from old to new???
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exactly. :)

As church says its the better result but takes more time so more expensive.
If you're gonna just make the join make sure you recess the float coat slightly to allow the skim to marry up level.
 
thanks guys this has helped alot fought i was doing somthing wrong just coudnt get it to stay on the wall that thick :mad: ..felt like a right plonker :-[ :-[ha ha ha ha ha ;
 
some of these damp jobs you might be thinking about having a good yard brush at the wall first, scrape off any remaining lime render then give it a good soaking with the hosepipe if you can...youll find it stays on the wall a lot better...
 
what sand was you using,worked for a damp company for 4 years we would use plastering sand and put sbr with the mix if it we were matching up to thick plaster worked a treat
 
what sand was you using,worked for a damp company for 4 years we would use plastering sand and put sbr with the mix if it we were matching up to thick plaster worked a treat
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how much do you add per mix iain?
 
about average size mug full per mix,also we used another product that was brilliant for thickning out will find out what that was had alot of beer since then memory cells have suffered
 
We do work for peter cox, rake out mortar for a key and coat with s&c (they give us an additive to stop salts and acts as a plasterciser). If its not too deep we will coat out and level off, but as you guys are saying a lot of the time it takes 2 coats. Had problems with the delta lath before if its not fixed properly and the weight of the coat will make it slide off! :mad:

Best to leave for a day or more for shrinkage. I always prefer to skim the full wall as i think its a far better finish.

Just make sure you follow the contractors spec for the guarantees!
 
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