Bottom line: Most interior walls in Southern Utah call for standard 1/2-inch drywall, but garages, bathrooms, and rooms near a furnace or water heater need a different board — moisture-resistant, fire-rated, or a thicker panel — and mixing them up costs a return trip to the yard. This guide breaks down the common types so you order the right board the first time.
What Drywall Thickness Do You Need?
Thickness depends on where the board is going, not personal preference. 1/2-inch is the standard for most interior walls and ceilings on 16-inch stud spacing. 5/8-inch is heavier and more rigid — it's the usual pick for ceilings on 24-inch spacing, garages, and anywhere fire-rated board is required. 3/8-inch shows up mostly in re-cover work over existing plaster or old lath, not new construction.
- 1/2-inch: standard walls and ceilings, 16" o.c. framing
- 5/8-inch (Type X): garages, ceilings on 24" o.c. framing, fire-rated assemblies
- 3/8-inch: re-cover/skim jobs over existing surfaces
Regular vs. Moisture-Resistant vs. Fire-Rated: What's the Difference?
The core gypsum is similar across types — the difference is the facing paper and additives that change how the board handles moisture or heat. Using regular board where moisture-resistant or fire-rated board is required isn't just a code issue, it shortens the life of the wall.
| Type | Common Name | Where It Goes |
|---|---|---|
| Regular | Standard/white board | Bedrooms, living rooms, hallways |
| Moisture-resistant | Green board / purple board | Bathrooms, laundry rooms, utility areas |
| Fire-rated | Type X | Garages, walls shared with living space, furnace closets |
| Cement board | Backer board | Behind tile in showers and tub surrounds (not a drywall substitute — a separate product) |
Moisture-resistant board is not waterproof — it resists humidity and occasional splashing in a bathroom, but it's not rated for direct, constant water exposure like a shower wall, which is where cement backer board takes over instead.
Do You Need Fire-Rated Drywall for a Garage?
In most attached-garage setups, any wall or ceiling shared with living space needs Type X (5/8-inch fire-rated) drywall — this is a common building code requirement across Southern Utah jurisdictions, though the specifics can vary by city, so it's worth confirming with your local building department or your contractor before you order. If you're working with a contractor on a garage build or remodel, our tips on working with contractors cover what to ask before materials get ordered so the spec matches what the inspector expects.
How Much Drywall Should You Order?
Measure total wall and ceiling square footage for the room, then order sheets to cover it with minimal cutting — 4x8 sheets (32 sq ft) and 4x12 sheets (48 sq ft) are both common, and larger sheets mean fewer seams to tape and mud. Add extra for waste around doors, windows, and outlets, and round up rather than down since a mid-job supply run costs more time than an extra sheet or two on hand.
- Measure each wall's length x height, plus ceiling area
- Subtract large openings only if they're a significant share of the wall
- Add a buffer for cuts and breakage
- Confirm sheet size availability before finalizing your count
We cover the different board types, thicknesses, and use cases in more depth in our drywall types guide if you want the full breakdown before you order.
Where to Buy Drywall in Southern Utah?
We stock regular, moisture-resistant, and fire-rated drywall at our Cedar City yard, serving contractors and homeowners across Southern Utah. Check current pricing before you place an order, and call ahead if you need a specific thickness or a larger quantity for a full remodel or new build so we can confirm it's on hand.