How many drywall sheets do I need for a 12x12 room?

A 12x12 room with 8-foot ceilings has approximately 384 square feet of wall space (minus doors and windows). Using standard 4x8 drywall sheets (32 sq ft each), you'd need about 12-14 sheets plus 10% waste allowance.

How much joint compound do I need per sheet of drywall?

Plan for approximately 0.053 gallons (or about 0.7 lbs) of joint compound per square foot of drywall for three coats. A standard 5-gallon bucket covers roughly 100-150 square feet.

How do I calculate drywall for a room with a ceiling?

Calculate total wall area (perimeter × wall height) plus ceiling area (length × width). Subtract openings for doors (typically 21 sq ft each) and windows (typically 15 sq ft each). Add 10% for waste and cuts.

FREE TOOL — UPDATED 2026

Drywall
Calculator

Estimate sheets, screws, joint compound, tape, and total project cost for any room — in seconds. Built for DIYers and contractors alike.

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4×8Standard Sheet

32 ft²Per Sheet

+10%Waste Factor

3Mud Coats

// THE CALCULATOR

Enter Your Room Details

Room Dimensions

Room Length (ft)

Room Width (ft)

Ceiling Height (ft)

Number of Doors

Number of Windows

Include Ceiling?

Sheet & Cost Settings

Sheet Size

Thickness

Cost per Sheet ($)

Waste Factor (%)

* Estimates for planning purposes. Always verify with your supplier before purchasing.

Your Material Estimate

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Enter room dimensions and click Calculate Materials to see your estimate.

0 Drywall Sheets

$0 Est. Sheet Cost

Material	Quantity	Unit
Total Area (gross)	—	sq ft
Net Area (openings removed)	—	sq ft
Drywall Sheets (w/ waste)	—	sheets
Drywall Screws	—	screws
Joint Compound (mud)	—	gallons
Joint Tape	—	linear ft
Corner Bead	—	linear ft
Est. Total Material Cost	—	USD

Cost Breakdown

Drywall Sheets$0

Joint Compound$0

Screws (1 lb box per 150)$0

Joint Tape$0

Total Estimate$0

// HOW IT WORKS

Four Steps to Your Material List

Measure Your Room

Enter your room's length, width, and ceiling height. Include or exclude the ceiling as needed.

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Count Openings

Add your number of doors and windows so we can subtract those areas from the total drywall needed.

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Set Sheet & Cost

Choose your sheet size, thickness, and enter your local material cost per sheet for accurate pricing.

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Get Your List

Instantly receive a full material list — sheets, screws, mud, tape, corner bead, and total cost estimate.

// REFERENCE GUIDE

Drywall Thickness Guide

Thickness	Best Use	Approx. Weight	2026 Avg. Cost
1/4 inch	Curved walls, layering over existing drywall	~1.2 lbs/sq ft	$8–$12/sheet
3/8 inch	Repairs, remodels, single-layer walls	~1.4 lbs/sq ft	$10–$14/sheet
1/2 inch ★	Standard walls & ceilings (most common)	~1.8 lbs/sq ft	$12–$18/sheet
5/8 inch	Fire-rated walls, ceilings, commercial use	~2.2 lbs/sq ft	$16–$24/sheet

// FAQ

Common Questions

How many drywall sheets for a 12×12 room?

A 12×12 room with 8-ft ceilings has roughly 384 sq ft of wall area. Subtracting a door (21 sq ft) and two windows (30 sq ft total), you're left with ~333 sq ft. Add 10% waste: ~366 sq ft. Using 4×8 sheets (32 sq ft each), you need about 12–13 sheets for walls only, or 16–17 sheets including ceiling.

How much joint compound do I need?

Budget roughly one 4.5-gallon bucket per 100 sq ft of drywall for a standard three-coat finish (taping, topping, and finish coats). Textured finishes may require more.

How many drywall screws per sheet?

Use approximately 28–36 screws per 4×8 sheet on walls (1 screw every 12 inches on edges, every 16 inches in the field). Ceilings may need more for safety — every 12 inches in both directions.

Should I add a waste factor?

Yes — always add at least 10% for cuts, mistakes, and irregular shapes. Complex rooms with many corners or angles warrant 15–20% waste. Our calculator defaults to 10%.

What size drywall sheets should I use?

4×8 ft sheets are the standard for most DIY projects (easy to handle solo). 4×12 or 4×16 ft sheets reduce seams and are preferred by pros, but require two people and more ceiling height clearance.

// FROM THE BLOG

Ready to Install? Read Our Complete Drywall Guide

Step-by-step installation tips, pro finishing techniques, common mistakes to avoid, and how to use this calculator to plan your project.

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GUIDE

The Complete Drywall Installation Guide for 2026

Everything from measuring and cutting to taping and finishing — written for DIYers and first-timers.

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