Drywall thickness and where each is used
| Job | Used for |
|---|---|
| ¼ inch Bends around curves; laminated over old plaster or damaged walls | Curves, overlays |
| ⅜ inch Overlays and some remodel work; rarely used alone | Overlays |
| ½ inch The standard for interior walls. Lightweight versions available | Most walls |
| ½ inch sag-resistant Made for ceilings on wider framing spacing | Ceilings |
| ⅝ inch (often Type X) Stiffer, better sound control, fire-rated when Type X | Ceilings, garages, fire walls |
Walls: ½ inch
Half-inch drywall on studs spaced 16 inches apart is the default for interior walls. A standard ½-inch 4×8 sheet weighs roughly 50 pounds; lightweight versions are noticeably lighter and easier to handle overhead.
Ceilings: ⅝ inch or sag-resistant ½ inch
Ceilings need stiffer board so it does not sag between joists over time, especially under the weight of insulation or a textured finish. Use ⅝-inch board, or ½-inch board labeled sag-resistant, and check the manufacturer's maximum framing spacing.
Garages and fire separation
Model residential codes require gypsum board between an attached garage and the house, and fire-rated ⅝-inch Type X board on the garage ceiling when there is a living space above. Type X has glass fibers in the core so it holds together longer in a fire. Local codes can add to this, so check before replacing drywall in a garage.
Bathrooms, basements and showers
Moisture- and mold-resistant drywall comes in the usual thicknesses and suits bathroom walls, laundry rooms and basements. It is not waterproof. Inside a shower or tub surround, tile needs a cement board or a waterproofed backer instead.
Match the thickness when repairing
A patch must be the same thickness as the wall around it, or the repair sits proud or sunken and shows through paint. Check the thickness at an outlet box, where the edge of the board is visible after removing the cover plate, or measure the edge of the hole. Older homes may have ⅝-inch walls or plaster instead of drywall; see plaster wall repair. For methods, see how to fix a hole in drywall, and for prices, drywall installation cost.
Common questions
What thickness is standard drywall?
Half an inch for interior walls in most homes. Ceilings and fire-rated areas often use ⅝ inch.
Is ⅝ drywall better than ½?
It is stiffer, blocks more sound and, as Type X, is fire-rated. It is also heavier and costs more, so it is used where those benefits are needed rather than everywhere.
Can I put ½-inch drywall on a ceiling?
Yes, if it is sag-resistant ceiling board and the joists are within the spacing the manufacturer allows. Regular ½-inch wall board is more likely to sag on ceilings.
Related guides
Based on manufacturer guidance and model residential code requirements; local codes vary. We update these figures as we complete jobs.