Choosing the Right Type of Drywall for Your Bathroom: Small Detail, Big Difference

You walk into your garage’s spare bathroom for the first time in ages. You catch a whiff of a damp, musty smell that you don’t ever remember being there before. Well, that can’t be good. Could this be what’s making your dog sick?

You’ve got to get that smelly drywall taken care of as soon as possible, before the mold growth makes anyone else sick or destroys your home’s interior wall framing.

In this article, the pros at Benson Drywall explain the four different types of drywall, which should be used in bathrooms, and what areas of bathroom walls they’re best suited for, to keep everything mold-free and the air clean.

What Type of Drywall Actually Belongs in a Bathroom?
4 Common Types of Drywall Used in Bathrooms
Choosing Drywall for Each Area of the Bathroom
Green Board vs. Cement Board: Which Should You Choose?
Frequently Asked Questions About the Best Type of Drywall for Bathrooms
Why Homeowners Trust Benson Drywall for Bathroom Projects in Portland

What Type of Drywall Actually Belongs in a Bathroom?

Bathroom walls need to be treated differently from those in the rest of the building. Because of the room’s specialized purpose and unique environment, there are certain types of drywall designed to be used to protect the wooden framing.

Because mold is a dangerously common health hazard in high-humidity locations, like full bathrooms, these drywall types were developed specifically to resist moisture and prevent mold growth.

Bathroom walls are typically lined with:

Standard drywall (with exceptions)
Moisture-resistant drywall
Mold-resistant drywall
Cement board

Why Bathroom Drywall Matters More Than You Think

The Impact of Moisture

Portland, Oregon, and most of the Pacific Northwest are known for their perpetually damp climate and extended rainy seasons, which means almost constant humidity. Older buildings do not typically have proper ventilation to deal with the constant moisture. This is a problem when using standard drywall in bathrooms.

The typical bathroom in a non-humidity-plagued climate already has high levels of moisture in the air, causing problems like deterioration and mold growth in standard drywall. Add in the extra humidity in Portland, and the potential for problems increases significantly.

When the Wrong Drywall Is Used

Benson Drywall is frequently called to address a number of moisture-related issues in both residential and commercial bathrooms including:

Sagging ceilings
Mold remediation
Homeowners insurance issues
Total replacement

Our experts have years of experience under their belts and understand which drywall type should be used and why. They exceed building standards and ensure each project is done precisely to avoid costly repairs in the future.

4 Common Types of Drywall Used in Bathrooms

#1: Standard Drywall (When It’s Acceptable – and When It’s Not)

Standard drywall, also known as gypsum drywall, should be used in common interior spaces. However, it’s not suited for high-humidity locations, such as full bathrooms, because it lacks any kind of special moisture resistance features. It is appropriate to use in half baths, though, because they do not include showers or bathtubs, which put the most moisture in the air.

#2: Moisture-Resistant Drywall (Green Board)

Green board, or moisture-resistant drywall, has a specially treated core and outward-facing paper that help prevent moisture absorption. However, it’s not waterproof. Despite its name, it doesn’t stand up to constant direct water spray, therefore we don’t use it in shower or tub surrounds.

It’s best used for:

Sink and vanity walls
Toilet walls
General perimeter walls
Bathroom ceilings with an exhaust fan
Half baths

#3: Mold-Resistant Drywall (Purple/Blue Board)

A more recent development in bathroom-appropriate drywall is the introduction of mold-resistant drywall, like Purple XP or Mold Tough. It offers better protection against moisture and mold than standard or green drywall products and is specifically designed to limit mold problems behind tiles and paint in humid environments like bathrooms.

However, like green and standard drywall, it is still gypsum-based and can absorb water from direct spray or prolonged moisture exposure. Avoid using it in showers and tubs.

We usually suggest that our clients use this type of drywall when installing or replacing their bathroom walls. It has the most protection of the three gypsum-based options and is easier to install than cement board.

#4: Cement Board and Fiber Cement Panels

Unlike the previous three types, cement board is not gypsum drywall. As its name explains, it’s made of cement and reinforcing fibers. Because it lacks paper, it deals far better with direct water.

Benson Drywall always suggests cement board for shower walls, tub surrounds, and other wet zones. Due to its heavier weight and difficulty to work with, we only use it for direct water contact areas and not where drywall is better suited.

Choosing Drywall for Each Area of the Bathroom

Best Type of Drywall for Bathroom Walls

Sink areas – Green board is appropriate because it only has intermittent moisture exposure from occasional splashes, humidity, and condensation from hot water.

Toilet walls – Moisture-resistant drywall is appropriate here due to the area typically experiencing only general bathroom humidity and occasional condensation.

Splash-prone surfaces – Mold-resistant drywall is designed for tub and shower walls outside the enclosure, and areas near sinks with repeatedly damp conditions, rather than occasional moisture. It’s more durable than green board and easier to install than cement board.

Best Type of Drywall for Bathroom Ceilings

The most common bathroom area to suffer the most from moisture or mold damage is the ceiling. Hot showers create steam that naturally rises and collects at the top of the bathroom. This means that they have longer exposure to moisture than walls. Even with exhaust fans running, the steam is not removed instantly and can linger on the ceiling surface, making it more susceptible to moisture absorption and mold growth.

Bathroom ceilings can sag when exposed to prolonged humidity and steam. A combination of moisture absorption and gravity pulls the softened drywall downward. Standard drywall is much more prone to sagging in bathroom ceilings.

Bathroom ceilings typically fail first because of:

Higher concentration of steam
Slowest drying time
Constant gravitational stress

Benson Drywall uses a thicker mold-resistant variety for bathroom ceilings. Thicker panels are stiffer and maintain better structural integrity. Mold-resistant drywall is designed to limit mold growth and performs better in consistently humid areas.

Best Type of Drywall for Bathroom Tub and Shower Surrounds

We understand the importance of meeting industry standards and do not use gypsum-based drywall in bathtub and shower surrounds. Instead, we use the recommended material, cement or fiber-cement board.

Cement board is preferred because it:

Has no paper facing
Is not damaged by water exposure
Is structurally stable in wet conditions

It’s commonly used behind:

Tile
Stone
Other hard, water-exposed finishes

Cement board is only used in wet zones because it’s heavier, more rigid, and harder to install than gypsum drywall.

Despite being better in wet zones, it is not waterproof. It won’t break down when wet, but water can still seep through it, allowing moisture to reach the wall framing. It’s vital to ensure proper layering to create a waterproof wall.

Proper layering for tub and shower walls:

Wall framing
Moisture barrier or surface waterproofing – Plastic sheeting or a liquid-applied waterproofing membrane on the cement board surface
Cement board – fastened with corrosion-resistant screws and joints taped with alkali-resistant mesh
Waterproofing membrane (if using surface-applied system) – Applied over corners, seams, and penetrations
Tile and grout – Can be paired with sealants

Green Board vs. Cement Board: Which Should You Choose?

Cost Differences and Long-Term Value

For homeowners concerned about costs, it’s essential to consider the appropriate drywall options for your bathroom build or repair.

While green board is less expensive than cement board, it doesn’t provide the superior water protection a shower or bathtub surround needs. If it’s used instead of cement board, you’ll likely cause unnecessary, costly repairs.

Cement board, though more expensive, provides lasting waterproofing for high-water contact areas.

Installation Considerations

It’s crucial to hire a professional drywall installation team, like Benson Drywall, because cement board requires specialized skills and knowledge to install. It’s even more important if you are transitioning from drywall to cement board because it needs careful sealing to stop moisture from seeping through.

Frequently Asked Questions About the Best Type of Drywall for Bathrooms

What Is the Best Drywall Finish for a Bathroom?

For most bathroom walls and ceilings, a moisture- and mold-resistant drywall covered with a high-quality paint or waterproof coating is best. For wet zones, cement board under tile is the industry standard for durability and long-term protection.

What Is the Best Thickness of Drywall for a Bathroom?

Typical bathroom walls should use ½-inch moisture- or mold-resistant drywall. Ceilings can use the same or use ⅝-inch for better sag-resistance. Cement board in wet zones is generally thinner, around ¼-inch to ½-inch, depending on the tile being used and local code requirements.

Do Building Codes Affect Bathroom Drywall in Portland?

Portland enforces Oregon’s statewide building code, which specifies the type of drywall that can be used in various locations within the bathroom. Controlling moisture in interior spaces is a core code principle. Under this code, bathrooms are classified as high-humidity environments, meaning materials must be made to handle damp air, condensation, and occasional moisture exposure.

Moisture- or mold-resistant in most of the bathroom is fine. Cement board in the bathtub and shower surrounds is required. Oregon codes also require mechanical ventilation in bathrooms.

Benson Drywall’s experienced installation team always meets or exceeds every Oregon building code in their bathroom projects.

Do I Still Need Moisture-Resistant Drywall if I Have a Bathroom Fan?

Yes. While a bathroom fan can help reduce humidity, it doesn’t eliminate moisture entirely. Bathroom fans and moisture-resistant drywall work hand-in-hand to prevent mold and deterioration.

Why Homeowners Trust Benson Drywall for Bathroom Projects in Portland

Whether you’re building something new, adding on an addition, or need repair work, Benson Drywall is up for any challenge. We’re known across Portland for our exceptional craftsmanship, honest work ethic, and delivering a top-quality experience every time.

Our experienced team of installers has a proven track record for meeting deadlines, staying on budget, and going above and beyond for our customers. We aim to build long-term relationships with our customers throughout Portland.