Question 1

How do you calculate drywall sheets needed?

Accepted Answer

To calculate drywall sheets needed: 1) Measure wall dimensions (length × height) for each wall and add them together. 2) Calculate ceiling area (length × width). 3) Subtract door (21 sq ft each) and window (15 sq ft each) openings. 4) Divide total square footage by sheet size (32 sq ft for 4×8, 48 sq ft for 4×12). 5) Add 10-15% waste factor for cuts and mistakes. Round up to the nearest whole sheet.

Question 2

What size drywall sheets should I use?

Accepted Answer

Standard drywall sheet sizes: 4×8 feet (32 sq ft) - Most common for walls, easy to handle, fits standard 8-ft ceilings. 4×10 feet (40 sq ft) - Good for 9-ft ceilings, reduces seams. 4×12 feet (48 sq ft) - Best for ceilings and tall walls, fewer seams but harder to handle. Use 1/2-inch thickness for walls with 16-inch stud spacing. Use 5/8-inch thickness for ceilings, fire-rated applications, or 24-inch stud spacing.

Question 3

How much does drywall cost per sheet?

Accepted Answer

Drywall costs vary by type and region: Standard 1/2" 4×8 sheet: $10-15. Standard 5/8" 4×8 sheet: $12-18. Moisture-resistant (green board) 4×8: $15-22. Mold-resistant (purple board) 4×8: $18-25. Fire-resistant Type X 4×8: $15-22. Longer sheets (4×10, 4×12) cost proportionally more. Professional installation adds $1.50-3.50 per square foot for labor. Total project cost typically $2.50-5.00 per square foot installed.

Question 4

How much joint compound do I need?

Accepted Answer

Joint compound (mud) requirements: 1 gallon covers approximately 100 square feet of drywall. For a typical room with 3 coats of mud: Use approximately 1 gallon per 100 sq ft. First coat (taping): heaviest use. Second coat (filling): moderate use. Third coat (finish): lightest use. Example: 500 sq ft room needs about 5 gallons. Always buy extra - leftover compound stores well. Pre-mixed compound is easiest for DIY. Powder mix is more economical for pros.

Question 5

How much drywall tape do I need?

Accepted Answer

Drywall tape requirements depend on seam length: Standard roll: 250-300 feet. Coverage: approximately 1 roll per 500 square feet of drywall. Calculate seam length: Count all horizontal and vertical joints, inside corners, and outside corners. Multiply by 1.1 for waste. Types of tape: Paper tape - traditional, requires embedding in mud, strongest. Mesh/fiberglass tape - self-adhesive, easier for DIY, good for repairs. Metal corner bead - for outside corners, sold by length.

Question 6

How long does it take to install drywall?

Accepted Answer

Drywall installation time varies by project size and skill: Hanging sheets: 1 hour per 4 sheets (professional), 2-3 hours (DIY). Taping and mudding: 3 coats required, 1.5 hours per 100 sq ft total. Drying time: 24 hours between coats. Sanding: 0.5 hours per 100 sq ft. Typical 12×12 room: Professional: 8-12 hours over 3-4 days. DIY: 20-30 hours over 1-2 weeks. Larger projects see efficiency gains. Include drying time in schedule.

Question 7

What is the best way to hang drywall?

Accepted Answer

Best practices for hanging drywall: Preparation: Install electrical and plumbing first, insulate walls. Layout: Start with ceiling, then walls. Run sheets perpendicular to joists/studs. Stagger seams for strength. Installation: Use drywall lift for ceilings. Place sheets tight against each other (no gaps). Leave 1/8" gap at floor for expansion. Fastening: Space screws 12" on ceilings, 16" on walls. Drive screws slightly below surface (dimple). Avoid breaking paper. Avoid placing seams at window/door corners.

Question 8

How many coats of joint compound are needed?

Accepted Answer

Standard drywall finishing requires 3 coats: First coat (taping coat): Embed paper tape in fresh mud over all seams. Fill screw holes. Let dry 24 hours. Sand lightly. Second coat (filling coat): Apply wider layer over seams (8-10 inches wide). Cover all fasteners again. Let dry 24 hours. Sand smooth. Third coat (finish coat): Apply thin, wide layer (12-14 inches). Feather edges smoothly. Let dry 24 hours. Sand with fine grit. Prime and paint after final sanding.

Question 9

Should I use 1/2 inch or 5/8 inch drywall?

Accepted Answer

Choose drywall thickness based on application: 1/2-inch drywall: Standard for walls with 16" stud spacing. Most common residential choice. Easier to cut and handle. Less expensive. 5/8-inch drywall: Required for ceilings in most codes. Better for 24" stud spacing. Fire-rated (Type X) applications. Better sound dampening. More sag-resistant. Code requirements: Check local building codes. Garages often require 5/8" Type X. Ceilings typically require 5/8" unless 12" spacing.

Question 10

How do you calculate drywall for a ceiling?

Accepted Answer

Calculating drywall for ceilings: Measure ceiling length and width in feet. Multiply: Length × Width = Square footage. Add 10% waste factor: Area × 1.10. Divide by sheet size (48 sq ft for 4×12 sheets). Round up to nearest whole sheet. Tips: Use 4×12 sheets for ceilings when possible (fewer seams). Run sheets perpendicular to joists. Use 5/8-inch thickness for proper support. Factor in tray ceilings or complex shapes separately. Consider professional installation - ceiling work is difficult.

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