Drywall Calculator Sheets. Drywall calculations require wall and ceiling area. Formula: Sheets equals Total Area divided by Sheet Size. Standard sheet: 4×8 feet equals 32 sq ft, also 4×12 available equals 48 sq ft. Calculate area: (Perimeter times Height for walls) plus (Length times Width for ceiling). Example 12×14 room, 8 ft ceiling: Walls 52 perimeter times 8 equals 416 sq ft. Ceiling 168 sq ft. Total 584 sq ft. Divide by 32 equals 18.25 sheets, buy 19 sheets plus 10 percent waste equals 21 sheets total. Orientation matters: Horizontal hanging reduces seams, professional standard. Vertical easier for DIY, more seams. Ceiling requires 5/8 inch thick vs 1/2 inch walls. Fire-rated (Type X) required garages, furnace rooms, attached dwellings. Moisture-resistant (green board) for bathrooms, purple board best for showers. Materials beyond drywall: Joint compound (mud) estimate 1 gallon per 100 sq ft finishing. Paper tape for flat seams, mesh tape for repairs. Corner bead metal or vinyl for outside corners. Screws 1-1/4 inch for 1/2 inch drywall, 32 per sheet minimum. Costs: Drywall sheets 10-15 dollars each for 1/2 inch 4×8, 12-18 for 5/8 inch, 15-25 for moisture-resistant. Installation labor 1.50-3.00 per sq ft. Finishing (taping, mudding, sanding) additional 1.50-3.00 per sq ft. Total installed finished 3-6 per sq ft. Example room 500 sq ft: Materials 250, hanging 1,000, finishing 1,000, total 2,250 or 4.50 per sq ft. Finishing levels: Level 0 no taping, temporary construction. Level 1 tape embedded, no finishing, garage ceiling. Level 2 coat over tape and fasteners, backsplash areas under tile. Level 3 two coats over tape, smooth, primer surface, flat paint ready. Level 4 three coats, smooth, for flat or eggshell paint. Level 5 skim coat entire surface, critical lighting or gloss paint, premium finish. Most homes Level 4 standard. Level 5 adds 1-2 per sq ft cost. Joint compound quantities: One 5-gallon bucket covers approximately 500 sq ft for Level 4 finish. Typical room uses 2-3 buckets through multiple coats. Taping coat thin, fill coat thicker, finish coat thin. Sand between coats. Use setting compound (hot mud) for first coat sets in 90 minutes, ready coat for finish easy to sand. Hanging drywall process: Measure and cut sheets to fit. Hang ceiling first, then walls. Horizontal orientation on walls. Stagger seams like bricks. Screw every 12 inches on studs. Dimple screws slightly below surface. Cut outlets and fixtures carefully. Taping process: First coat apply tape with thin mud. Second coat fill over tape, cover screws. Third coat feather edges wide 10-12 inches. Fourth coat skim finish if needed. Sand smooth between coats. Prime before painting. Common mistakes: Not accounting waste for cuts around windows and doors, add 10-15 percent. Using wrong thickness ceiling needs 5/8 inch, walls 1/2 inch standard. Forgetting corner bead for outside corners. Insufficient joint compound buying only one bucket. Not sanding between coats creates rough finish. Hanging vertically increases seam count and finishing time. Pro tips: Use 12 ft sheets on longer walls reduces seams. Back-block seams where studs don't align adds support. Pre-fill large gaps with setting compound before taping. Use inside corner tool makes corners faster. Sanding pole with vacuum attachment reduces dust. LED work light highlights imperfections. Mesh tape faster but paper tape stronger. Tools required: Drywall saw for cutting. Screw gun or drill with depth setting. T-square for measuring. Taping knives 6-inch, 10-inch, 12-inch widths. Mud pan. Sanding pole. Utility knife. Stilts optional for ceilings. Scaffolding or drywall lift for large ceiling sheets. DIY vs professional: DIY hanging moderate difficulty, taping requires skill and patience. Professional hangers install 500-800 sq ft per day. Professional tapers finish 500 sq ft per day through all coats. Beginners allow 3-4 times longer. Practice on garage or closet first. Ceiling drywall: Use 5/8 inch thickness prevents sagging. Install perpendicular to joists. Screw every 12 inches on joists. Consider using adhesive plus screws. Get helper for ceiling panels, heavy and awkward. Moisture areas: Use purple board (mold-resistant) behind shower tile. Green board bathrooms and laundry. Regular drywall adequate in low-moisture areas. Never use regular drywall in direct water contact. Cement board required shower surrounds under tile. FAQ: How many sheets for 10×12 room? Approximately 15-17 sheets including ceiling and waste. Cost to drywall 1,000 sq ft? Materials 500, installation 4,000-6,000 finished. Can I DIY drywall? Hanging possible for DIYer, finishing difficult requires practice. How long to finish? Professional 1,000 sq ft in 3-5 days through all coats. DIY may take 2-3 weeks. What finish level? Level 4 standard for most homes.