Sand & cement ,Suction control

wil

Member
Evening fellow spreads
I have a big problem, started scratching up exterior walls for smooth float finish render,
It seems to pull in too quickly to flatten properly, which does concern me for when we start ruling off and floating up.
I have tryed sbr on the back ground 50/50 water and sbr brushed on to substrate but not really much different.
The morter joints are lime morter and we were working in the shade so it was not the sun.
Can anyone advise me pls
 
My float coat will consist of lime and plasterciser and the other the 2 binders s& c, would anyone add a retarder of any sort or just keep soaking?????
 
Keep soaking it till the suction slows right down and surface stays damp long enough to get a coat on , or scud it, or lath/mesh it.
 
If watering down doesn’t help then use Rendagrip.

Sbr will need putting on the day before so as to create a skin. Then apply as a tack coat.
 
Evening fellow spreads
I have a big problem, started scratching up exterior walls for smooth float finish render,
It seems to pull in too quickly to flatten properly, which does concern me for when we start ruling off and floating up.
I have tryed sbr on the back ground 50/50 water and sbr brushed on to substrate but not really much different.
The morter joints are lime morter and we were working in the shade so it was not the sun.
Can anyone advise me pls
What mix was your scratch cost ?
 
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These sprayers are good for damping down, less drastic than a mains fed hose pipe
 
If watering down doesn’t help then use Rendagrip.

Sbr will need putting on the day before so as to create a skin. Then apply as a tack coat.
Can I pick your brains aswell please, I’ve got the same problem going on. Got to top some walls but the labourer hasn’t put any waterproof additive in the scratch mix (I always have waterproofed in scratch unless it’s freezing cold winter) so no waterproofed in scratch coat and in the baking summer heat even with a good wet down it’s going to pull in quick, we can get a waterproofed/retarder additive in the top coat to help a bit. Any recommendations for a good retarder/waterproofs/plasticiser? Also is it a completely ridiculous idea to just roller some diluted waterproofer on to the scratch? Like pva-ing but just with waterproofer ? Is that just completely stupid? Has anyone ever tried that?
 
Can I pick your brains aswell please, I’ve got the same problem going on. Got to top some walls but the labourer hasn’t put any waterproof additive in the scratch mix (I always have waterproofed in scratch unless it’s freezing cold winter) so no waterproofed in scratch coat and in the baking summer heat even with a good wet down it’s going to pull in quick, we can get a waterproofed/retarder additive in the top coat to help a bit. Any recommendations for a good retarder/waterproofs/plasticiser? Also is it a completely ridiculous idea to just roller some diluted waterproofer on to the scratch? Like pva-ing but just with waterproofer ? Is that just completely stupid? Has anyone ever tried that?


Can’t see rolling the waterproof additive on working. Wetting it down will still pull at the top but no suction at all at the bottom. I would use a 50/50 water and sbr solution the day before. It doesn’t work same day.
 
Can I pick your brains aswell please, I’ve got the same problem going on. Got to top some walls but the labourer hasn’t put any waterproof additive in the scratch mix (I always have waterproofed in scratch unless it’s freezing cold winter) so no waterproofed in scratch coat and in the baking summer heat even with a good wet down it’s going to pull in quick, we can get a waterproofed/retarder additive in the top coat to help a bit. Any recommendations for a good retarder/waterproofs/plasticiser? Also is it a completely ridiculous idea to just roller some diluted waterproofer on to the scratch? Like pva-ing but just with waterproofer ? Is that just completely stupid? Has anyone ever tried that?
Is it practical to pop by the day before, late afternoon evening and hose them down, proper drench them. Did this recently, panel was nice and green in the morning floated lovely.
 
Is it practical to pop by the day before, late afternoon evening and hose them down, proper drench them. Did this recently, panel was nice and green in the morning floated lovely.
That would be a good idea but it’s a big panel on two levels internally, dick head architect has got a fetish for rendered walls inside! So it’s not a good idea to get the hose out really and soak the house, I’m pretty pissed off with the guy who scratched it because there was a lot of discussion beforehand about having waterproofer in the scratch especially in the summer months but the advice has not been taken on board and now it’s going to be more difficult than it needed to be.
 
That would be a good idea but it’s a big panel on two levels internally, dick head architect has got a fetish for rendered walls inside! So it’s not a good idea to get the hose out really and soak the house, I’m pretty pissed off with the guy who scratched it because there was a lot of discussion beforehand about having waterproofer in the scratch especially in the summer months but the advice has not been taken on board and now it’s going to be more difficult than it needed to be.

Use your pump action spray bottle, roll a dust sheet up and lay on the floor and spray away. I've got a couple of them like yours if you want an extra one. Same principle. Don't be keen, until it's green. Good luck amigo
 
You will still need some suction on the scratch if its internal float which wont cause any problems as its not a finish and only the backing coat for skim .
 
You will still need some suction on the scratch if its internal float which wont cause any problems as its not a finish and only the backing coat for skim .
It’s sponge finished render inside , not skimming over it. The pva idea doesn’t seem quite right though? I think it’s just going to need a thorough wet down if I get there early in the morning and wet down twice before 8am and more guys one or two just floating up while the others coat it on.
 
Just make a slurry if you would really struggle and the pva is not bad idea as is internal and won’t be exposed to the elements. Pva is water soluble and if rain doesn’t get to it or over excess water would be more than ok. Saying all that..... I’ll still do slurry and apply the float coat while still green. Wet the wall before that or the slurry will go ballistic.
 
Evening fellow spreads
I have a big problem, started scratching up exterior walls for smooth float finish render,
It seems to pull in too quickly to flatten properly, which does concern me for when we start ruling off and floating up.
I have tryed sbr on the back ground 50/50 water and sbr brushed on to substrate but not really much different.
The morter joints are lime morter and we were working in the shade so it was not the sun.
Can anyone advise me pls
Get the hose pipe on it before you start rendering my mate give it a good wet down have cup tea and cake then start
 
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