What to do to seal old wallpaper paset on walls?

[acknowledged74]

Hi

I have had some walls plastered and used pva glue as a sealant to paint over. This works fine.

Many of the other wall are stained (tried sugar soap) and have wallpaper paste on, I simply don't have weeks to get all of this off, and have tried its an absolute nightmare (each normal sized wall is taking a bay). When I have tried painting directly over the paste (even in places where I've taken most of it off) it all gloops up. Can I use the pva sealant as a way around this, and to create a seal? I would just seal over these bit and leave the rest lightly sanded then emulsioned?

I just need it to look nice to sell on.

 

[acknowledged74]

anyone have any ideas on this one?

Pretty please

 

[Deccy]

NEVER use PVA before applying paint!!

 

[acknowledged74]

OK so what to use instead to deal with the paste issue?

I have always used diluted 5:1 on fresh plaster, isn't that whats its for?

 

[jondecs]

I have always used diluted 5:1 on fresh plaster, isn't that whats its for?

Nope!! it's for quick fixers. It may seem ok at the time but all them walls you say you pva'd will result in a future trail of misery of, bubbling, flaking, pinging off if knocked and when paper has been stripped from a pva primed wall , most of paint will come off leaving a very untidy wall which will need to be lined or skimed.
Use a mist coat== 30% thinned emulsion for first coat then a bit thicker coat. I usually get finished in two coats... But not uncommon to need 2 coats ontop of mist.

You need to line if you can't be bothered to get paste of m8
might be your only option now you painted over paste..

Good luck..

 

[acknowledged74]

Can't mist coat the paste just mixes with the paint and gloops.

Linings not an options, 1. because would take just as long to get done, and more importantly I can't do it myself.

Isn't there primer or something else that I can use?

 

[opps]

i use a sander connected to a dust extractor to remove old paste. 9 times out of 10 I line the walls though.

I agree that pva on plaster is not a good move.

If you dont have a sander you will need to wash the walls a few times, Zinsser make a (wall paper remover) liquid with enzymes that break down the paste.

 

[JohnD]

to clean off paste, I use warm water and a wide metal scraper. just keep wiping the slimy paste off the scraper with rag or kitchen roll.

I suppose you might be able to get PVA off the same way, but it would be very tiresome and I'm sure would make you wish the PVA hadn't been put on the wall.

matt emulsion, thinned with water, is the best thing to seal a plaster wall.