PVA as a Primer on Wallpaper

[EN4]

Hi All,

I need to paint over fairly porus wallpaper in our bedroom and wondered what sort of diluted concentration on PVA to water I should use????

PS: Can't really removed the paper to paint, as the walls are really bad underneath.

Thanks for any help and assistance.

EN4

 

[TheDec]

Never ever use PVA if you intend to apply paint, if your paper is paintable use a slightly thinned emulsion and forget the PVA.

Dec

 

[EN4]

Really? Will that be a better sealant/primer?

Do you mean thin down a cheap emulsion before applying the paint we want?

What about using Zinsser BIN ?

Thanks for all and any help.

 

[TheDec]

If you were to apply pva your paint would not stick to it, if you intend to apply an emulsion paint just slightly thin your first coat.

Dec

 

[EN4]

Thanks Dec.. and what about Zennser BIN is that any better??

 

[TheDec]

If your wallpaper is paintable there will be no need to apply the Bin.

Dec

 

[TheDec]

Some walpapers will accept an emulsion paint and some dont and there are varying reasons for this, if there is any form of doubt in your mind that an emulsion paint wont adhere simply apply a thinned oil based undercoat before you apply your emulsion.

Dec

 

[EN4]

If your wallpaper is paintable there will be no need to apply the Bin.

Dec

My only concern was making the wallpaper soggy with the paint and thus bubbling up.. I was thinking that a primer or sealant would have formed a better bond to stop this.

The paper is smooth and fairly plain.

Can i ask, what will watered down emulsion do over just putting on the neat emulsion?

Cheers

EN4

 

[EN4]

Can anyone input into this?

Thanks

EN4

 

[TheDec]

If you apply an emulsion paint to wallpaper the moisture content contained within it will have a tendancy to reactivate the paste thus causing the bubbling effect of which you speak, this is a normal reaction and providing that the paper was hung correctly it will dry back as both paper and emulsion dry out, you can both prevent/eliminate this by the use of a sealer coat and in your situation if you fell the need a thinned oil based undercoat would suffice.

Dec

 

[EN4]

Thank you.. can you give me some examples of oil based undercoats i could use.. sorry for being a bit dim

 

[TheDec]

I could offer you many, just pop into your local shed B&Q or Wickes and just use one their own brands.

Dec

 

[EN4]

Please give me an example link, as i haven't a clue what i'm looking for !

 

[Growler]

First -

Choose the emulsion you want.

Second -

Apply some on a smallish section of your wallpaper.

Third-

If your paper looks good when it's dried, carry on painting.

Fourth -

If it doesn't,

Dec will walk you through that scenario if/when it happens.

 

[EN4]

How is it best to thin an oil based paint please?