A little help please

[jonnyg]

I Have rendered a 3 sqmtr wall scratch coat 3-1 mix over mesh background haven't been able to finish it of yet and its dry will i have to damp down or give it a coat of pva. Didn,t add any admixture in scratch coat but was going to add a bit of waterproofer to floating coat sorry for newbie question but hardly get any rendering jobs so a bit inexperianced at it

 

[bodplasterer]

Just wet it down give it a good soak but its only 3m2 so you shouldnt struggle with that.

 

[PhilPlaster]

I'd still add the waterproofer though.

 

[jonnyg]

thanks what would happen if i did pva the wall i havent but you get different advice

 

[bodplasterer]

Plus with your topcoat you want to go 4-1 mix as you need to go weaker on the next coat i personally do 4-1 scratch with waterproofer and 5-1-1 topcoat the extra 1 is lime and a bit of feb to cream it up a bit.

 

[jonnyg]

will it affect render if i didnt put wateproofer in scratch coat i intend to put it in floating coat though with a bit of plasticiser

 

[bodplasterer]

No it wont affect the render it will just pull in faster but on a small area like that it wont make a lot of difference.

 

[pwi]

just give a good soaking and add some waterproofer do not pva

 

[flat boy skim]

I'm with bod

 

[nickelarse]

prob dont even need to wet it down. just chuck it on. ull be done in an hour

 

[kirk johnstone]

yes mate soak the wall first, if you dont the scratch coat will suck the water out of the top coat before it has chance to set. give the wall a good soak, there will be a shine/glisten on the wall wait for this to go (otherwise your top coat will just slide around on the water) and then commence with the top coat

 

[plasterjfe]

No pva. I wouldnt bother with waterproofer either stick some plasterciser in it. just wet the background and lash it on. 3.1 is a bit strong so in future think about 4.1 - 5.1 or 5.1 -6.1 depending on background

 

[jonnyg]

thanks for your help guys do you need to use pva on outside render at all either on wall or in mix is it always better to have a mesh background or a slurry coat as base for scratch coat

 

[PhilPlaster]

dont pva outside mate. Question.... if hes going over the scatch coat same day he doesnt need to put in a waterproofer in does he? Wont feb/plasterciser on its own by ok?
So 4x1 washed sand, leave ,scratch. Then top coat 5x1 all with feb in.