Plaster walls feel harder, are often thicker, and usually sound solid when tapped. Drywall has a more uniform surface and sounds slightly hollow. Small tests like tapping, poking, or removing an outlet cover can quickly reveal which one you have.
How to Tell If Your Walls Are Plaster or Drywall
Whether you’re patching a hole, hanging shelves, or prepping for paint, knowing whether your walls are plaster or drywall can save you time, tools, and frustration. While they serve the same purpose, they’re built completely differently—and require different repair approaches.
In this guide, we’ll walk you through simple tests, signs to look for, and what each wall type means for your next home project.
Why It Matters
Before we dive in, here’s why this matters:
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Repair materials differ: Drywall compound won’t bond well to traditional plaster.
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Tool choice changes: Anchoring in plaster requires a different approach than in drywall.
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Historical context helps: Older homes may have hidden issues that newer walls don’t.
🔎 Quick Visual and Physical Clues
1. Age of the Home
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Built before ~1950? Likely plaster.
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Built after 1960? Most likely drywall.
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1950s–60s homes? Could be either, or a mix.
In Cleveland and Northeast Ohio, many pre-war and early post-war homes still have original plaster walls.
2. Wall Texture and Seam Visibility
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Plaster: Subtle texture, possible hairline cracks, no visible seams or screw heads.
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Drywall: Smoother, seams may be faintly visible under paint, especially at corners or ceilings.
Plaster can have a more organic, slightly uneven surface. Drywall is generally flat and consistent.
3. The Knuckle Test (Tap It)
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Plaster: Feels rock solid, makes a sharp, dense sound.
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Drywall: Slightly softer knock, sounds hollow between studs.
Try this in a few spots. If some areas sound hollow and others solid, you might have plaster over drywall or wood paneling beneath—not uncommon in older remodels.
4. The Pushpin Test
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Pushpin won’t go in? Probably plaster.
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Pushpin glides in with firm pressure? Drywall.
This is an easy, low-impact test in a closet or hidden corner.
5. Check Inside an Outlet Box
Turn off the power and carefully remove a faceplate. Look inside the wall cavity.
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Plaster: You’ll likely see layers—plaster about 1/2″ thick over wooden lath strips or metal mesh.
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Drywall: One uniform sheet about 1/2″ thick with paper on both sides and chalky gypsum in the middle.
If you see wood strips with gaps, it’s old-school lath and plaster.
Deeper Structural Differences
| Feature | Plaster | Drywall |
|---|---|---|
| Common in Homes Built | Before 1950 | After 1950 |
| Composition | Lime or gypsum over wood/metal lath | Paper-faced gypsum board |
| Wall Thickness | 3/4″ to 1.25″ | 1/2″ or 5/8″ standard |
| Durability | Very hard, resistant to dents | Softer, easier to damage |
| Repair Difficulty | More time-consuming | Easier to patch or replace |
Common Mix-Ups
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Skim Coat Confusion: Some drywall has a thin coat of plaster over it, making it harder to tell.
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Plasterboard: A transitional material used in the 1940s–50s that looks like drywall but is treated like plaster.
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Textured Paints: Heavy textures can mask drywall seams and throw you off.
What If You Have a Combo?
It’s not unusual to have plaster downstairs and drywall upstairs after a renovation—or even different materials in different rooms.
Check behind radiators, basement stairs, or in unfinished closets for clues. In Northeast Ohio, many older homes have layered systems: original plaster walls with drywall patches or full replacements from past decades.
What It Means for Your Project
If you’re planning repairs or upgrades, here’s how the material affects the job:
For Hanging Heavy Items
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Plaster: Use masonry bits, toggle bolts, or find a stud—anchors don’t hold well.
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Drywall: Use drywall anchors or self-tapping screws; easy to modify.
For Painting
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Plaster: May need patching hairline cracks and spot-priming.
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Drywall: More uniform finish, but edges and seams may flash if not properly prepped.
For Patching
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Plaster: Needs plaster-compatible compounds and sometimes mesh repair.
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Drywall: Spackle or joint compound works fine.
FAQs
Can a house have both plaster and drywall?
Yes—especially in homes remodeled over decades. You might even find plaster walls with drywall ceilings or vice versa.
Is plaster better than drywall?
Plaster is more durable and soundproof but harder to repair. Drywall is easier to work with and cheaper to install. It’s a tradeoff depending on your needs.
Can I drill into plaster like drywall?
Not exactly. Plaster can crack if drilled incorrectly. Use a masonry bit, go slow, and avoid hammer drills unless anchoring into lath-backed walls.
What’s behind plaster walls?
Usually wooden lath strips (older homes) or metal mesh (newer plaster jobs). You may also find brick, stone, or framing directly behind in some homes.
Is it worth replacing plaster with drywall?
Not unless the plaster is severely damaged. Repairing is often more cost-effective and helps maintain historic charm.