PVA Plasterboard?

Discussion in 'Builders' Talk' started by fred812, Nov 20, 2017.

  1. fred812

    fred812 Screwfix Select

    Well I think its plasterboard!

    Removed a built in wardrobe and have uncovered a strip of plasterboard(?) about 300mm wide and the height of the room that needs a skim of about 1mm. Its been in there about 20 years, colour grey if that helps. Can't get a pro to do it quickly so will have a bash myself. Done a bit of Googling and can't establish whether I should PVA the board first?

    Anyone offer any advice please?

    Thanks.
     
  2. DIYDave.

    DIYDave. Screwfix Select

    This strip, does it look/feel like the surface is paper ? Then it’s gotta be PB surely ?

    No need to seal, it’s designed to skim straight over

    If your not used to plastering, (I’m diy myself and attempt majority of jobs but not plastering) :mad: maybe think about using Easifill 20

    As in the title, gives you around 20mins working time, good drying time also and is easy to sand down - if you need to ! (I know that I would)

    It’s harder though to get the joints either side to be invisible though

    If it was me, I would scrape down either side of the PB strip to taper the edges of the plaster

    Check the PB is really firm with no movement before skimming, with anything - good luck
     
  3. fred812

    fred812 Screwfix Select

    Thanks DIY Dave, very helpful. Yes feels like paper. Reason I'm having a go myself is that I have to get the room finished and cos I've got a good edge each side I reckon I'll be able to get a reasonable enough finish for wall paper. I'll trim the edges like you say. I've even got some Easifill 20, great stuff!!
     
  4. CGN

    CGN Screwfix Select

    If it's old plasterboard, then I'd PVA it if I was skimming it.
     
  5. fred812

    fred812 Screwfix Select

    Is PVA safe option? Like if it doesn't really need it but I do it, will it be ok?
     
  6. CGN

    CGN Screwfix Select

    Just belt and braces Fred. Dave is correct in that you don't usually need to PVA plasterboard, however old PB is hit and miss, so if it was my job, I'd slap a bit on.
    You can PVA new PB with no real adverse effects...just no need to.
     
  7. As Dave says, run a blade down each edge of the existing plaster skim to bevel/taper it towards the exposed p'board. Good chance you'll also find there are raised bits of plaster along these edges - almost certain if it was skimmed up to the old wardrobe.

    As you say, having a surface guide on each side will help to set the level for you - this is as easy as a first skimming gets! But don't be dismayed if it's still more awkward than you imagined, or if the finished dry plaster still needs a sanding - that's all ok.

    Some of the sorts of wee issues you may find is that the absorbency levels of that strip will be different - the actual bare plasterboard will be ok - just the 'right' amount - but the exposed edges of the old skim will likely suck like a sucky thing, and you may even find that two little tramlines of fresh skim will dry along that edges as you smooth down and might even go 'crumbly' on you - grrrrrr. If so, just spray a small amount of water along it, and smooth again - it'll soon stop sucking.

    PVAing beforehand would help this, so you could run the PVA along the old skim edges to balance it. But, wipe off any PVA that ends up on the top existing wall surface - you don't want it there (just use a damp cloth).

    There are differing suggestions of how to use PVA - most pros seem to suggest allowing it to go 'tacky' before skimming. I have tried this and found it reactivated so much with the wet plaster than I was simply pushing a blob of plaster all over the wall trying to make it flatten. It was like skimming on to oil. So I let the PVA fully dry first and found this was ideal for skimming on to.

    Your call as to whether to use PVA. If you don't, then run a wet paint brush or similar up these old skim edges and let it soak in before applying your skim. (If it soaks in instantly, then apply another brushing. But don't get it 'wet', just damp. If it's wet, leave it for a good 10 minutes first.

    A nice DIY task.

    Don't forget to post before and after photos :D:p
     
  8. fred812

    fred812 Screwfix Select

    Thank you for all your help and advice. Yes, photos will be taken and posted if it goes ok.
     

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice