Paint over wallpaper

[ccmm]

Hi! DH and I are planning to paint our home. Most rooms have wallpapers on which previous owners have painted at least once. The condition of the wallpaper and wall are all good. We never painted before and have some questions.

1. Do we have to use a primer? Some online articles mention the risk of wallpaper peeling off without a primer. Would love to know if anyone has experience/knowledge on this.
2. Do we have to use oil-based primer? Oil-based ones are relatively high in VOCs. We're quite cautious as moving in already and having kids. We choose a water-based paint as well for same reasons.

My understanding is that primer is used to seal the wallpaper. Previous owners should have sealed it when they painted, presumably? So do we need to do it again?

1. We found this water-based primer from Dulux which says "no stripping of wallpaper needed". Can we use this one if primer is necessary?

www.diy.com/departments/dulux-walls-white-primer-undercoat-5/5010212641316_BQ.prd

Thanks in advance!

I've painted over wallpaper many times...never used primer. Not sure if there's been a change in the formulation of wallpaper paste which might have necessitated this?
The times I've painted over rather than stripping have been due to costs, and primer is £££ so I've just used ordinary paint.

We painted over our hall wallpaper with F&B modern emulsion, the wallpaper had been previously painted with silk emulsion, paint is fine, we didn't use any primer, we did use a similar colour though and only used one coat which covered the old paint, we will probably recoat in a few years time

I asked my decorator this when he was wallpapering, and he said you can just treat it like lining paper and paint over it. I don’t know how many times, but yes it’s possible. I don’t think you need a primer. I guess it depends on the paper.

The silk emulsion we used originally was put onto shiny anaglypta type wallpaper and it still kept on fine, we used silk as DS was small and it was more wipeable

Thank you everyone for sharing your experiences! It is reassuring!
Previous owner just confirmed that they laid lining paper instead of wallpaper on the wall, so it is fine to use water-based primer or paint over.

Yes avoid extra unnecessary coats. The paper can start to bubble up.