While the term "ceiling wall" is not standard (ceilings are horizontal, walls are vertical), if you are referring to the thickness of the ceiling material itself, 5/8-inch is a common thickness for drywall used on ceilings.
Understanding Ceiling Thickness
The thickness of a ceiling is primarily determined by the material used to finish the underside of the structural framing (joists or trusses). The most common material for this is drywall (also known as gypsum board or plasterboard).
Common Drywall Thickness for Ceilings
According to construction standards and practices:
- 5/8-inch drywall is generally reserved for use on ceilings and in commercial construction jobs.
This thickness is often preferred for ceilings compared to thinner options like 1/2-inch or 3/8-inch drywall for several key reasons:
- Sag Resistance: Ceilings are susceptible to sagging between joists due to gravity and the weight of the material. Thicker 5/8-inch board provides better rigidity and sag resistance over longer spans.
- Fire Resistance: 5/8-inch drywall often has a higher fire-resistance rating, providing more time in the event of a fire.
- Soundproofing: As noted in the reference, its thickness makes it a preferred choice for soundproofing spaces that expect plenty of noise.
Comparison of Drywall Thicknesses
Here's a simple comparison of common drywall thicknesses:
| Thickness | Common Use Cases | Notes |
|---|---|---|
| 3/8-inch | Wall repair, curved surfaces | Lightest, least common for new construction |
| 1/2-inch | Standard interior walls | Most common for walls |
| 5/8-inch | Ceilings, fire-rated assemblies, commercial walls | Heavier, more expensive, better sag/sound |
Note: While 5/8-inch is common for ceilings, 1/2-inch sag-resistant drywall is also sometimes used, depending on joist spacing and local codes.
In summary, the material typically used for ceilings, particularly drywall, often comes in a thickness of 5/8-inch due to its enhanced properties suitable for overhead application.
