ᐅ Non-woven wallpaper on aerated concrete blocks – primer, sealer, or a combination?

Hi everyone,

We have a beige wallpaper that we want to apply to an aerated concrete wall in the living room. Now, we’re unsure whether to use a primer (deep primer is recommended for aerated concrete because it is very absorbent), a white wallpaper primer (which is recommended for light-colored non-woven wallpapers), or both. At the hardware store, a young employee (who seemed a bit overwhelmed) said that first a deep primer should be applied, then painted with white, and only then should the wallpaper be put up.

I hope there are some experts here who can clarify this. 🙂

Good luck

I don’t understand. Is the aerated concrete wall unplastered? If so, it’s not even Level 1 finish, so how is a non-woven wallpaper supposed to look on it?
If it is plastered, then the aerated concrete no longer matters; instead, it depends on the absorbency of the plaster. The plaster thickness is around 15–20mm (0.6–0.8 inches), and the primer won’t penetrate that deeply at all.

Primer is definitely necessary, always and everywhere. With gypsum plaster, once is enough; with aerated concrete, probably two or three times, because it soaks up a lot.

Regarding the paint... gypsum plaster is white, aerated concrete is white... even lime plaster, which is now rather uncommon in living areas, is white.
So why paint over it again with white paint?

If in doubt, you should try this first on a short wall length, maybe a room corner or around a window or a door...

Valid point. I checked underneath, and it’s white plaster. So, should a wallpaper primer be enough, or is a deep primer still necessary?