The Best Drywall for ADU Construction: Why 5/8″ Should Be Your Go-To Choice

When you’re building an ADU, every choice matters. You’re not just trying to pass inspections, you’re trying to build something that feels solid, safe, and permanent. Drywall is one of those details that seems small, but it affects fire rating, sound control, durability, and the final look of your space.

One of the most common questions we get is: Should I use 1/2″ drywall or 5/8″ drywall for my ADU?

Technically, 1/2″ drywall is slightly cheaper. But in real-world ADU projects, that difference is usually so small that it doesn’t justify giving up the benefits of 5/8″.

What’s the Real Price Difference Between 1/2″ and 5/8″ Drywall?

From a good supplier, the difference is usually about $1–$2 per sheet. Most ADUs use well under 300 sheets, which means:

• The total material difference is often just a few hundred dollars
• Labor stays the same
• The performance benefits far outweigh the cost difference

Why 5/8″ Drywall Is Better for ADU Builds

Why We Recommend 5/8″ Drywall for Most ADUs

Because it improves fire safety, improves sound control, improves finish quality, makes walls feel stronger, and costs very little more. It’s one of the few upgrades that improves multiple parts of the build at once.

This is why we don’t see 5/8″ drywall as “overkill.” We see it as doing things right the first time.

Drywall Finish Matters Just as Much

ADUs usually have strong lighting, smaller rooms, and tighter spaces — that means drywall finishing quality matters more. Most ADUs work best with standard smooth (imperfect smooth), a Level 4 finish, or light hand texture depending on style.

5/8″ drywall gives us a better base to work from, which means cleaner corners, better ceiling lines, and a finish that looks intentional.

Drywall for ADUs Is About the Full System

Drywall isn’t just sheets on studs. It’s part of a system that includes:

• Insulation
• Fire separation
• Sound control
• Finish quality
• Long-term durability

We often bundle insulation and drywall together for ADU projects because it simplifies scheduling, keeps costs tighter, and ensures the wall system performs correctly.

The Short Answer

If you’re building an ADU: 5/8″ drywall should be your default choice. The price difference is minimal, labor doesn’t increase, fire safety improves, sound control improves, and finish quality improves.

Unless you’re working on an unusually massive project or extreme access conditions, 5/8″ drywall is simply the smarter option. It’s a small decision that pays off for the life of the building.

Choosing 5/8-inch board is only half of it; how it is hung and finished is the other half, which is where ADU drywall installation in San Diego comes in.