Pva

[Eddie]

I have a wee problem. I am meant to be starting a bathroom this week, the lady came along to tell me it was ready to go, but then let me know that they had PVA'd the new plasterboard. Can PVA be removed from plasterboard? or is there anything that we can do without replacing all the plasterboard?

Cheers, Eddie

 

[Ajax123]

I have a wee problem. I am meant to be starting a bathroom this week, the lady came along to tell me it was ready to go, but then let me know that they had PVA'd the new plasterboard. Can PVA be removed from plasterboard? or is there anything that we can do without replacing all the plasterboard?

Cheers, Eddie

belt sander should take the most of it off. loads of dust though......

 

[Eddie]

I didn't wan't to use a sander on plasterboard.

 

[mikethetile]

i was going to say sand it

 

[Eddie]

Would priming over pva help?

 

[Ajax123]

Would priming over pva help?

Nope......sorry

 

[mikethetile]

problem is you cant prime over pva Eddie

there is a thread on here that covers this and will explain it better than me

 

[Eddie]

Suppose it will have to be sanded.
if it goes too far i will just have to replace the boards.

 

[Ajax123]

main problem is thart PVA mainly stays on the surface as a film and very little penetrates the surface of the plaster. This means the mechanical key is relatively weak compared to a penetrative acrylic or epoxy primer. the only realistic way to get it off is to scarify it some how. wire brush, sander etc. There are one or two enclosed sanding systems available that limit the dust. The other issues are that if it gets wet (water based adhesive???) it re emulsifies. That will cause the tiles to fall off. Additionally if you can get them to stick Poly Vynil Acetate is highly susceptible to alkali burn which breaks it down over a period of time.

Has no place in tiling I am afraid.........

 

[mikethetile]

main problem is thart PVA mainly stays on the surface as a film and very little penetrates the surface of the plaster. This means the mechanical key is relatively weak compared to a penetrative acrylic or epoxy primer. the only realistic way to get it off is to scarify it some how. wire brush, sander etc. There are one or two enclosed sanding systems available that limit the dust. The other issues are that if it gets wet (water based adhesive???) it re emulsifies. That will cause the tiles to fall off. Additionally if you can get them to stick Poly Vynil Acetate is highly susceptible to alkali burn which breaks it down over a period of time.

Has no place in tiling I am afraid.........

thats why i didnt try and explain

well explained ajax

 

[Dan]

main problem is thart PVA mainly stays on the surface as a film and very little penetrates the surface of the plaster. This means the mechanical key is relatively weak compared to a penetrative acrylic or epoxy primer. the only realistic way to get it off is to scarify it some how. wire brush, sander etc. There are one or two enclosed sanding systems available that limit the dust. The other issues are that if it gets wet (water based adhesive???) it re emulsifies. That will cause the tiles to fall off. Additionally if you can get them to stick Poly Vynil Acetate is highly susceptible to alkali burn which breaks it down over a period of time.

Has no place in tiling I am afraid.........

Well put mate.

 

[Eddie]

Thanks guys, you have just confirmed my thoughts.

Cheers, Eddie

 

[DHTiling]

Wet the wall lightly.. and then rub over with a scotch pad.. DO NOT soak the wall...

BUT if the pva was diluted to the extent it did not create a skin , then it will be ok to tile over.

 

[Ajax123]

Scotch Pads - wot a good idea. Dave the Save....you da man

 

[aqua blue]

I didn't wan't to use a sander on plasterboard.
__________________

It's a 'long shot', but a hairdryer may heat it enough so as it could be peeled off.

Works with vinyl film, some acrylic paints and stubborn masking tape.