Skimming Over Painted Wall Problem

woolley_2

Hi, hope someone here can offer some advice. House I recently bought has textured paint or artex over nearly every wall / ceiling in the house.

As I've re-skimmed quite a few rooms before in my old house I decided to get busy with this one. All was going well, two and half bedrooms done until I tackled one wall in the third bedroom. Same textured paint as all the others so as usual I scraped off what I could of the texture, PVA'd it about 2 parts water :1 part PVA and skimmed it to a nice finish. Two days later the new coat had dried but felt brittle in places. I picked off the loose bits as thought it might be a small area that hadn't taken but realised I could easily pick off the skim coat in huge pieces. Basically it hadn't adhered to the wall at all so I scraped it all off - it was very easy and re-tried a small portion of the wall with a stronger PVA solution 1/1 but again two days later it hadn't bonded again.

Its really puzzling me as I've completed two walls in the same room - same old textured paint backing etc and that feels nice and solid and well bonded. Its just this one wall that doesn't seem to want to play ball.

Sorry to turn this question into 'War and Peace' everyone but does anyone know how I can tackle this - should I scrape the old paint off first back to the original plaster with a heat gun or use a bonding coat over the painted wall first - any help massively appreciated - thanks in advance.

PS - I'm using Thistle Multi-Finish plaster for skimming - browny/pink coloured and mixing well to a creamy reasonably wet consistency.

snowboardjon

I'm not a plasterer, but my advice would be to try a bag of Thistle bonding coat, you mix & apply it exactly the same as you do multi finish. It's only a couple of £'s for a big bag and in my experience it tends to stick to anything. Then skim over the top of that with multi finish.

Worth a try.

woolley_2

Thanks snowboardjon - Think I'll probably give that a try - sounds quicker than a labour intensive stint with the heat gun!

cargo

Pva.Then spread a tight coat of carlite bonding rub up with your float eg: plastic or wood float with nails in it to leave key.Then skim as you normally would.
Thats what i would say without seeing.

If to late how have you gone on with it?

Rhino666

Just had a plasterer in my house and the best advice he could give was 1:1 PVA/water followed by the thistle bonding coat, which cost £4.73 or thereabouts from Wickes. As the guy above says you then use your Thistle multifinish on top.

Your problem does sound odd though - is the PVA adhereing to the textured finish ?
What element is actually causing the key breakdown ?

Good luck !

woolley_2

Thanks everyone for your advice. I am going to redo it tomorrow. Having spoken to a plasterer as well about it I will first try to key it really well by scratching the surface as much as possible to break through the paint layer and then PVA it totally neat. Then start to apply the finish as soon as the PVA starts to go tacky. Should know by end of weekend if its been a success. If not I will go and try bonding coat first. I'm confident though that with a really well keyed surface results should be better.

Rhino666 - Thanks - The wall insn't textured that much really now anyway - the combination of scrapeing (it was that coarse textured paint with big bits in it) with a heavy duty floor scraper and then taking off the coat of skim I put on has left it smoother. God knows if I carry on like this I could end up with a totally smooth wall without skim!! The PVA didnt appear to adhere to the wall last time at all. On reflection my estimates for my mix of PVA in my first post were probably inaccurate - I guess maybe 4W:1PVA then 2W:1PVA. Also I may have started too quickly with the finish straight on to the wet PVA instead of letting it bond and dry a little bit first to the wall which would have provided the tackiness and suction for the finish.

I will post my results back for you guys by Sunday - Thanks again