The most beautiful wallpaper in the world will telegraph every flaw beneath it. Here is what happens before the first strip goes up.
Wallpaper is honest. Whatever lies beneath it — a patched hole, a ridge of old paint, a hairline crack — eventually shows through, especially under raking light from a window or a sconce.
That is why preparation is not a preliminary step. It is the foundation of the result. A careful installer begins by reading the wall: checking for moisture, testing old coatings, and noting where the surface is out of plumb.
Old wallpaper usually needs to come down completely. Layering new paper over old risks adhesion failure and visible seams from the layer below. Removal is followed by washing off residual paste, which can otherwise react with new adhesive.
Next comes repair and skim coating where needed. The goal is a uniformly smooth, sound surface. Then a wallcovering primer is applied — it evens out porosity, improves adhesion, and makes future removal far easier.
Only then does measuring and layout begin. The time spent here is invisible in the finished room, and that is exactly the point.