Drywall: A Complete Guide to Installation, Repair, and Finishing

Publish on: 18-Mar-2025

Drywall is an essential part of modern construction, used in both residential and commercial buildings. Whether you’re remodeling a home, constructing an office, or just making repairs, understanding drywall can help you achieve a smooth and professional finish.

In this guide, we’ll cover what drywall is, why it’s popular, how to texture it, its pros and cons, the right sandpaper grit to use, alternatives, cost estimates, and how long drywall mud takes to dry.

What is Drywall?

Drywall, also known as gypsum board or sheetrock, is a building material used for interior walls and ceilings. It consists of a gypsum core sandwiched between two layers of paper. This makes it lightweight, easy to install, and a more efficient alternative to traditional plaster walls.

Drywall comes in different types, including regular drywall, moisture-resistant (green board), fire-resistant (Type X), and soundproof drywall. Each type serves specific purposes depending on the project requirements.

Why is Drywall Popular?

Drywall is widely used in construction for several reasons:

Easy to Install – Drywall panels are lightweight and can be quickly attached to wall studs with screws or nails.
Cost-Effective – It is more affordable compared to traditional plaster walls and requires less labor.
Fire Resistance – Gypsum contains water molecules that help slow the spread of fire.
Energy Efficiency – It provides insulation, helping to regulate indoor temperatures.
Smooth Finish – Once taped, sanded, and painted, drywall creates a seamless and polished appearance.

Pros and Cons of Drywall

Pros:

Affordable – Cheaper than plaster.
Quick Installation – Takes less time compared to traditional methods.
Fire-Resistant – Some types offer extra protection against fire.
Energy Efficient – Helps with insulation and noise reduction.

Cons:

Easily Damaged – Drywall is prone to dents and holes.
Not Water-Resistant – Regular drywall absorbs moisture, leading to mold if not treated.
Messy Repairs – Patching requires sanding, which creates dust.

Working with drywall

Working with drywall can be both straightforward and challenging, depending on the project’s complexity and your skill level. Here’s a breakdown of the experience:

The Good

Beginner-Friendly Basics:
- Cutting drywall is simple with a utility knife and straightedge.
- Hanging sheets on walls is manageable for DIYers with basic tools (screws, drill, level).
Quick Transformations:
- Instantly creates smooth walls or ceilings, hiding pipes, wires, or uneven surfaces.
Affordable Material:
- Drywall itself is inexpensive (typically 10–20 per 4x8 sheet).
Customizable:
- Can be painted, textured, or used as a base for tiles/wainscoting.

The Challenges

Heavy and Awkward:
- Sheets weigh 50–80 lbs; ceiling work often requires a lift or extra hands.
- Large sheets are unwieldy in tight spaces.
Mudding & Taping:
- Joint compound ("mud") requires skill to apply smoothly.
- Feathering seams and avoiding bubbles/bulges takes practice.
- Sanding creates fine dust (wear a mask and seal the room!).
Time-Consuming:
- Multiple coats of mud (with drying time in between) add days to projects.
- Rushing leads to visible seams or cracks later.
Repairs Can Be Tricky:
- Patching holes or water damage often requires precise cutting and blending.

How much drywall do i need?

You can calculate how much drywall you need for your project using manual or online drywall calculator.

To calculate how much drywall you need, use the following formula:

Let:

$A_{total}$ = Total wall/ceiling area (square feet)
$A_{sheet}$ = Area of one drywall sheet (square feet)
$N$ = Number of drywall sheets required

Formula:

$N = \frac{A_{total}}{A_{sheet}}$

Step-by-Step Calculation:

Find the total wall/ceiling area:

$A_{total} = Height \times Width (for each wall, then sum up)$

Determine the area of one drywall sheet:

$A_{sheet} = Sheet Length (m) \times Sheet Width (m)$

(Common drywall sizes: 4 ft × 8 ft = 32 sq ft, 4 ft × 12 ft = 48 sq ft)

Calculate the number of sheets required:

$N = \frac{A_{sheet}}{A_{total}}$

Round up to the next whole number, as drywall sheets cannot be purchased in fractions.

How Long Does Drywall Mud Take to Dry?

Drywall mud, or joint compound, typically takes 24 hours to dry between coats. However, drying time depends on:

Humidity & Temperature – High humidity slows drying; using a dehumidifier speeds it up.
Type of Mud – Fast-setting compounds dry in 30 minutes to 2 hours.
Thickness of Application – Thicker layers take longer to dry.

To speed up drying, use fans, dehumidifiers, or lightweight joint compound.

What Grit Sandpaper for Drywall?

When sanding drywall, the right sandpaper grit makes a big difference:

120–150 grit – Ideal for smoothing joint compound without removing too much material.
180–220 grit – Used for final finishing before painting.

How Much Does Drywall Cost?

The cost of drywall depends on the type and thickness:

Standard drywall (4x8 ft sheet, 1/2-inch thick) costs $12–$20 per sheet.
Moisture-resistant drywall (green board) costs $15–$25 per sheet.
Fire-resistant drywall (Type X) costs $20–$30 per sheet.
Labor costs range from $1.50–$3 per square foot, depending on complexity.

For an average 12x12 ft room, expect to pay $500–$1,500 for materials and installation.

Final Thoughts

Drywall is an essential building material due to its affordability, ease of installation, and versatility. Whether you’re working on a home project or a commercial build, knowing how to install, texture, and finish drywall can make a big difference. By using the right sandpaper grit, choosing the right type of drywall, and understanding cost factors, you can achieve a smooth and professional finish.

For those looking to avoid dust, alternatives like wet sanding or sanding sponges can be helpful. And when working with drywall mud, allowing proper drying time ensures a flawless result.

With the right tools and techniques, you can master drywall installation and finishing with confidence