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Measure the total wall or ceiling area in square feet (height x width for each surface), subtract door and window openings, then divide by the sheet size you plan to use (32 sq ft for 4'x8' sheets). Add 10% for waste and cuts.

4'x8' sheets are the most common and easiest to handle. 4'x12' sheets are ideal for rooms with 9-foot or higher ceilings because they reduce the number of seams. 4'x10' sheets split the difference for standard 8-foot walls hung horizontally.

1/2" is the standard thickness for most walls. 5/8" is required for ceilings (to prevent sagging), garage walls adjacent to living spaces (fire code), and fire-rated assemblies. 1/4" and 3/8" are used for curved walls and overlay repairs.

A good rule of thumb is about 1 screw per square foot of drywall, or roughly 28-32 screws per 4'x8' sheet. Screws should be placed every 12 inches along edges and every 16 inches in the field (center of the sheet).

Plan for approximately 0.053 gallons (about 3.5 pounds) of joint compound per square foot of drywall. A 4.5-gallon bucket covers roughly 85 square feet of drywall for three coats of taping, bedding, and finishing.

Sheetrock is a brand name for drywall made by USG Corporation. Drywall is the generic term for gypsum board panels. They are functionally identical -- "sheetrock" is simply the most well-known brand, similar to how "Kleenex" refers to tissue.

Horizontally is preferred for walls because it reduces the total linear feet of seams, creates stronger joints across studs, and is easier to finish. Vertical hanging is acceptable for walls shorter than 4 feet or in commercial applications with metal framing.

Standard 1/2" thick 4'x8' drywall costs about $12-$16 per sheet. 5/8" fire-rated sheets cost $16-$22. Moisture-resistant (green board) costs $14-$20. Prices vary by region, quantity, and supplier.

Add 10% for standard rectangular rooms. Use 15% for rooms with many openings (doors, windows) or complex layouts. For L-shaped rooms or rooms with angles, 15-20% is recommended because of increased cutting waste.

Yes, but it is significantly harder than walls. Use 5/8" drywall for ceilings to prevent sagging. A drywall lift (rentable at most hardware stores) is almost essential for ceiling work. Screws should be spaced every 12 inches on ceiling joists.