Gypsum Board
The panel behind most interior walls and ceilings, also called drywall.
Quick Answer
Gypsum board, also called drywall or wallboard, is a panel with a gypsum core faced with paper or fiberglass mat, used to finish interior walls and ceilings. Installed over metal or wood framing, it provides a smooth surface and, in rated assemblies such as Type X, contributes to fire resistance and sound control.
The Full Picture
Gypsum board is a manufactured panel made of a gypsum core pressed between facing sheets of heavy paper or glass mat. It is the dominant interior finish material in commercial and residential construction because it is economical, fast to install, fire-resistant by nature of the gypsum core's chemically bound water, and easy to finish.
Panels are fastened with screws to light-gauge steel or wood framing to form partitions and ceilings. Product types serve different needs: regular panels, Type X and Type C for fire-rated assemblies, moisture- and mold-resistant panels for wet areas, abuse-resistant and impact-resistant boards for corridors, and exterior sheathing panels. Standard thicknesses include one-half and five-eighths inch, and fire-rated assemblies commonly use five-eighths-inch Type X.
A fire-rated wall is an assembly, not just a board. Its rating comes from a tested design listing, which specifies the framing, board type and layers, insulation, fasteners, and joint treatment. Sound ratings work similarly. Substituting components can invalidate the rating, so assemblies are identified on the drawings by listing numbers and typically referenced in the specifications.
Finishing quality is described by finish levels, from Level 0 (no finish) through Level 5 (a skim coat over the entire surface), defined in industry standards such as GA-214. The level should match the final wall treatment, since glossy paint or critical lighting calls for higher levels. Quantities are usually measured by area, with framing, insulation, and finishing counted separately.
Real Examples
Common Misconceptions
People assume: Any gypsum board makes a wall fire rated.
Actually: Only a tested, listed assembly achieves a rating, and it depends on the framing, board type, layers, and installation details. Standard board alone does not guarantee a rating.
People assume: Moisture-resistant drywall is waterproof.
Actually: It resists moisture better than regular board, but it is not waterproof. Wet areas still need an appropriate waterproofing system and details.
Does MeltPlan Solve This?
Partially — adjacentMeltPlan does not install or design partitions. It can help with the quantity side: MeltPlan Takeoff uses AI plus US-based estimators to measure wall and ceiling areas and related interior quantities from plans, and Design Review can flag missing or inconsistent requirements across the drawing set.
Get drywall and partition quantities taken off from your plans →Frequently Asked Questions
Is drywall the same as gypsum board?
Yes, in everyday use. Drywall, wallboard, plasterboard, and gypsum board all refer to the same type of panel, though technical documents usually say gypsum board.
What is Type X gypsum board?
A gypsum board with a specially formulated core, often with glass fibers, that performs better in fire tests. It is used in fire-rated assemblies when included in a listed design.
What are drywall finish levels?
A scale from Level 0 to Level 5 describing how much joint compound and finishing is applied. Higher levels create smoother surfaces for critical lighting or glossy finishes.
How is gypsum board measured for estimating?
Usually by surface area, such as square feet of wall or ceiling, with separate counts for framing, insulation, accessories, and finishing.