Preparing different surfaces for paint

[Philip_of_Smeg]

Hello

I plan on painting a room that has a mixture of newly skimmed and old previously wallpapered walls. I was initially going to use Zinsser Gardz on all the walls but thought that might be expensive but I would if it was best. Now I'm thinking about mist coating the new plaster and using Gardz for the old walls that used to be wallpapered. The old walls seem to have patches of old paint/plaster/white chalky surface.

I'm not sure what the best approach is so just wanted some help and advice on whats best.

Thanks
Philip

 

[Wayners]

Bodge cheap orbital sander with 120grade sanding discs on vacuum as that will remove most of the paste.
Use gardz over the lot. 2.5lt goes along way. Beeline sealer is cheaper and I've used that many times.

2.5lt if Gardz is £30. Not too bad

 

[Philip_of_Smeg]

Thanks for your reply.

I've been reading about allowing walls to breathe and I understand Gardz isn't breathable. Will the walls be ok sealed with Gardz, it won't cause any issues later on?

Thanks

 

[Wayners]

You have lime plaster and no cavity walls?

 

[Philip_of_Smeg]

You have lime plaster and no cavity walls?

I think it's lime plaster, I'm sure that's what the plasterer said. We have cavity walls though.