# Drywall and plasterboard calculator

> Drywall sheets for a room's walls and ceiling after doors and windows, with screws, joint tape and compound, for 4 × 8 ft or metric plasterboard.

직접 계산할 수 있는 페이지: https://www.calcopenly.com/ko/construction/drywall-calculator
분야: 건축 및 주택 계산기

Board area is the wall area, 2 × (length + width) × height, plus the ceiling if included, minus doors and windows. Sheets to buy are that area plus waste divided by the area of one sheet, rounded up. Screws, tape and joint compound scale with board area at the rates used here: one screw, 0.37 ft of paper tape and 0.009 US gal of all-purpose compound per square foot.

The default 14 × 12 ft room with 8 ft walls, a ceiling and 36 ft² of openings has 548 ft² of board. With 10% waste that is 19 sheets of 4 × 8 ft, about 548 screws, 203 ft of tape and 4.9 gal of compound, or two 4.5 gal pails.

Metric sheets such as 1200 × 2400 mm are converted exactly, so results match in either unit. The drawing shows where sheet joints fall on each wall; it does not plan cuts, which is what the waste allowance covers.

## 입력

- **Room length**
- **Room width**
- **Wall height**
- **Include the ceiling**
- **Doors and windows (total area)**: About 21 ft² per door and 15 ft² per window.
- **Sheet size** (선택 항목: 4 × 8 ft, 4 × 10 ft, 4 × 12 ft, 1200 × 2400 mm, 1200 × 2700 mm, 900 × 1800 mm)
- **Waste allowance**: 10% covers cut-offs around openings; use 15% for rooms with many corners.

## 결과

- Sheets to buy (sheets) — 주요 결과
- Board area (ft²)
- Board area (m²)
- Screws (screws)
- Joint tape (ft)
- Joint tape (m)
- Joint compound (US gal)
- Joint compound (L)
- 4.5 gal pails of compound (pails)

## 공식

$$
N = \left\lceil \frac{\big(2(\ell + w)h + \ell w - A_{\text{open}}\big)(1 + \text{waste})}{A_{\text{sheet}}} \right\rceil
$$

## 계산 예제

### 14 × 12 ft room, 8 ft walls and ceiling, 4 × 8 sheets

- Room length: 14 ft
- Room width: 12 ft
- Wall height: 8 ft
- Doors and windows (total area): 36 ft²
- Sheet size: 4 × 8 ft
- Waste allowance: 10%
- **Board area: 548 ft²**
- **Sheets to buy: 19 sheets**
- **Screws: 548 screws**
- **Joint tape: 202.8 ft**
- **Joint compound: 4.93 US gal**
- **4.5 gal pails of compound: 2 pails**
- 검증 출처: Python decimal: 2(14 + 12) × 8 + 168 − 36 = 548 ft²; × 1.1 ÷ 32 = 18.84 → 19; tape 0.37 × 548 (USG); compound 9 gal per 1,000 ft² (USG)

### Metric 4 × 3 m room, 2.4 m walls only, 1200 × 2400 sheets

- Room length: 4 m
- Room width: 3 m
- Wall height: 2.4 m
- Include the ceiling: 아니요
- Doors and windows (total area): 0 ft²
- Sheet size: 1200 × 2400 mm
- Waste allowance: 0%
- **Board area: 33.6 m²**
- **Sheets to buy: 12 sheets**
- 검증 출처: Hand calculation: 2(4 + 3) × 2.4 = 33.6 m² ÷ 2.88 m² per sheet = 11.67 → 12

### Edge: 8 ft cube walls fit whole sheets exactly

- Room length: 8 ft
- Room width: 8 ft
- Wall height: 8 ft
- Include the ceiling: 아니요
- Doors and windows (total area): 0 ft²
- Sheet size: 4 × 8 ft
- Waste allowance: 0%
- **Board area: 256 ft²**
- **Sheets to buy: 8 sheets**
- **4.5 gal pails of compound: 1 pail**
- 검증 출처: Hand calculation: 4 walls × 64 ft² = 256 ft² = 8 sheets of 32 ft² with no remainder

## 자주 묻는 질문

### How many sheets of drywall do I need?

Add the walls, 2 × (length + width) × height, and the ceiling, subtract doors and windows, add waste and divide by the sheet area. A 14 × 12 ft room with 8 ft walls has 416 ft² of wall and 168 ft² of ceiling; less 36 ft² of openings that is 548 ft². With 10% waste it needs 18.8 sheets of 4 × 8 ft (32 ft²), so buy 19.

### How many sheets of drywall for a 12 × 12 room?

19 sheets of 4 × 8 ft for walls and ceiling at 8 ft high, with 10% waste and no openings deducted. The walls are 2 × (12 + 12) × 8 = 384 ft² and the ceiling 144 ft², 528 ft² in all, or 16.5 sheets before waste. With 4 × 12 ft sheets (48 ft²) the same room needs 13.

### What drywall is required between a garage and a house?

At least ½ in gypsum board on the garage side of the wall separating the garage from the house, and 5/8 in Type X gypsum board where the garage has habitable rooms above it (2021 IRC Table R302.6). Sheet thickness does not change the sheet count here; order the thickness the code or your plans call for.

### How much joint compound and tape do I need for drywall?

This calculator allows 370 ft of paper tape and 9 US gal of all-purpose compound per 1,000 ft² of board, which is 0.37 ft and 0.009 gal per square foot. For 548 ft² that comes to 203 ft of tape and 4.9 gal of compound, two 4.5 gal pails. Coverage differs between compound types, so compare with the figure on the pail.

### “Drywall and plasterboard calculator”의 정확도는 어느 정도인가요?

정확도는 입력값과 계산 방법의 가정에 따라 달라집니다. 십진 연산은 유효숫자 50자리를 사용하지만, 추정값·수치해석 방법·원본 데이터의 정밀도는 더 낮을 수 있습니다. 표시값을 반올림해도 이러한 한계는 사라지지 않습니다. 독립적인 출처의 풀이와 대조한 계산 예시: 3. 예를 들어 “14 × 12 ft room, 8 ft walls and ceiling, 4 × 8 sheets”은 Python decimal: 2(14 + 12) × 8 + 168 − 36 = 548 ft²; × 1.1 ÷ 32 = 18.84 → 19; tape 0.37 × 548 (USG); compound 9 gal per 1,000 ft² (USG)와 대조해 확인합니다.

### 이 계산 방법의 출처는 무엇인가요?

USG Sheetrock paper joint tape — coverage about 370 ft per 1,000 ft² of board; USG Sheetrock UltraLightweight joint compound — about two 4.5 gal pails per 1,000 ft²; USG Gypsum Construction Handbook — screw spacing 12 in on ceilings, 16 in on walls; International Code Council — 2021 IRC Table R302.6: garage separation, ½ in gypsum board on the garage side, 5/8 in Type X under habitable rooms.

## 출처

- [USG Sheetrock paper joint tape — coverage about 370 ft per 1,000 ft² of board](https://www.usg.com/api/download-center/v1/assets/f6d373bc-3db0-5da7-9c1e-88bad68531cb?download=true&country=us)
- [USG Sheetrock UltraLightweight joint compound — about two 4.5 gal pails per 1,000 ft²](https://assemblies-tools.usg.com/content/usgcom/en/products/walls/drywall/joint-compound/ultralightweight-joint-compounds/sheetrock-ultralightweight-joint-compound.html)
- USG Gypsum Construction Handbook — screw spacing 12 in on ceilings, 16 in on walls
- International Code Council — 2021 IRC Table R302.6: garage separation, ½ in gypsum board on the garage side, 5/8 in Type X under habitable rooms