How to Prep Walls Before Wallpapering

Step-by-step

1. Clear and clean the wall

   Remove nails, screws, and wall anchors, then wash the wall with a mild detergent to strip grease, grime, and dust — adhesive won't bond well to a dirty surface.

2. Strip old wallpaper if there is any

   New wallpaper hung over old, peeling, or bubbled paper will inherit and often worsen those flaws. Remove existing paper first unless it's fully sound and your new wallpaper is specifically rated to go over it.

3. Fill holes and sand smooth

   Patch nail holes, dents, and seams with spackle or joint compound, then sand flush once dry. Wallpaper — especially lighter, non-textured styles — shows through surface imperfections more than paint does.

4. Apply a wallpaper primer or size

   A dedicated wallpaper primer (sometimes called "size") seals the wall, promotes adhesion, and makes future removal far easier by keeping paste from soaking directly into bare drywall paper or plaster.

5. Let the primer dry fully before hanging

   Follow the primer's dry-time instructions exactly — hanging wallpaper over primer that hasn't fully cured can trap moisture and cause adhesion problems later.

Why priming matters

Bare drywall is porous — it absorbs paste unevenly, which can starve the adhesive and lead to curling seams or bubbles soon after installation. A wallpaper primer creates a consistent, sealed surface so paste behaves the same way across the whole wall, and it gives you a much easier removal job whenever this wallpaper eventually comes down, since the paste bonds to the primer layer rather than directly to the drywall paper.

New drywall vs. painted walls

New, unpainted drywall needs a primer before wallpaper regardless of anything else — it's too absorbent to paste over directly. Previously painted walls need less prep if the paint is in good condition (a light sanding to dull a glossy sheen is usually enough), but a wallpaper primer is still worth applying, since it standardizes adhesion and makes future removal cleaner regardless of what paint is underneath.

Common mistakes

• Hanging wallpaper directly over unprimed drywall, leading to bubbling or paste starvation.
• Skipping patch-and-sand on "minor" dents that show through under raking light once wallpaper is up.
• Using a general-purpose primer instead of one formulated for wallpaper adhesion.
• Hanging before the primer has fully cured, per the can's instructions.