Why is SBR not killing suction

F

Fopar

New Member
Hi all, just having an issue with the last couple of ceilings that I’ve done and I could do with some input and advise please,

Previously plastered and painted ceilings in fair condition, not big 1&1/2 bags
I Gave them a good coat of neat SBR using a roller and let it pull in, after 20-30mins ceiling looked ready to go, nice shine on it from the SBR so good to go I thought
But first coat pulled in really quick , speed skimmed it and 2nd coat was the same ,
like I’d not even prepped them, ended up laying them down and had to 3rd coat the last ceiling, which I know is naughty as it’s a lot of product.
For you guys out there that use SBR as a pre skim prep,What am I doing wrong?
Thanks Kev
 
teenager GIF
 
Fopar said:
Hi all, just having an issue with the last couple of ceilings that I’ve done and I could do with some input and advise please,

Previously plastered and painted ceilings in fair condition, not big 1&1/2 bags
I Gave them a good coat of neat SBR using a roller and let it pull in, after 20-30mins ceiling looked ready to go, nice shine on it from the SBR so good to go I thought
But first coat pulled in really quick , speed skimmed it and 2nd coat was the same ,
like I’d not even prepped them, ended up laying them down and had to 3rd coat the last ceiling, which I know is naughty as it’s a lot of product.
For you guys out there that use SBR as a pre skim prep,What am I doing wrong?
Thanks Kev
Click to expand...
Brand?
 
Don't fully seal until dry.
Product needs to harden by drying to create a seal.
i would seal. 24 inch fan to dry off quicker. Another coat and when tacky skim.

One thing though. I don't think plaster sticks better when tacky Vs dry. Watch the the test on YouTube
 
Works best if you SBR the day before.
Then I skim onto the dry SBR.
Some might suggest it's better to then apply a second coat of SBR and let go tacky before skimming, though I've rarely done that and never had a problem.
Same story with PVA, as the background draws moisture through the PVA from the plaster, re-emulsifying the PVA.
However, for high suction backgrounds, SBR kills suction way better than PVA, in my experience.
 
Old thread,




But I'd rather 5w and 1s, at least 20 mins then 50/50.

One coat is never great in my opinion, as you can push dust and shite around in that application. One sealer - let it pull in and then go on fresh, either let that go tacky or dry, far better job.

SBR is such a concentrated product, neat is far too strong for these circumstances.


People are fooled by it's runny consistency, it's 3 times stronger for sealing than PVA.
 
You must log in or register to reply here.
Back
Top