FAQs

Find answers to your questions about walls, why they’re important and how they can add lasting value to your home.

Drywall & Cement Board Basics (3)

Drywall – also known as gypsum board or wallboard – is a naturally fire-resistant, paper-covered sheet of natural or synthetic gypsum used to build interior walls and ceilings in most homes.

While all gypsum-based drywall is naturally fire-resistant, PURPLE® drywall is unique because it also resists moisture, mold and mildew. In addition, most PURPLE® drywall products also stand up to scratches, scuffs, dents and sound.

Drywall is used to create the walls and ceilings in the non-wet areas of your home. While standard drywall is likely appropriate for low-activity, low-moisture spaces, PURPLE® drywall offers added benefits for areas that need it – for example, mold and moisture resistance in the bathroom or basement, sound resistance in the bedroom or nursery, or protection against car door dings and accidental holes in the garage.

Cement board – also known as backerboard – is specially designed for use in place of drywall behind tile in the wet areas in bathrooms and kitchens. It’s hard, durable, naturally moisture- and mold-resistant, and won’t rot, disintegrate or swell when exposed to water. PermaBase® Cement Board is ideal for use behind tile in showers, tubs, backsplashes and countertops, and behind exterior finishes such as thin brick, stucco and manufactured stone.

No. While all drywall is naturally fire-resistant, PURPLE® drywall is unique because it also resists moisture, mold and mildew. Most PURPLE® drywall products also stand up to scratches, scuffs, dents and sound. This means added value and peace of mind regardless of steamy showers, roughhousing kids or band practice.

All PURPLE® products have achieved GREENGUARD GOLD Certification for indoor air quality and are as easy to install and finish as standard drywall.

About Purple (11)

PURPLE® drywall stands up to what standard drywall can’t, including moisture, mold, mildew, scratches, scuffs, dents and sound. These added benefits – for example, mold and moisture resistance in the bathroom or basement, sound resistance in the bedroom or nursery, or protection against car door dings and accidental holes in the garage – give homeowners greater value and extra peace of mind.

What’s more, all PURPLE® products are naturally fire-resistant, have achieved GREENGUARD GOLD Certification for indoor air quality and are as easy to install and finish as standard drywall.

National Gypsum has been making PURPLE® products for more than a decade.

Headquartered in Charlotte, N.C., National Gypsum is one of the largest gypsum drywall manufacturers in the country. The company owns and operates a network of drywall, joint compound and cement board plants across the United States and Canada.

It would cost less than $1,000 to upgrade an average 2,500-square-foot house to PURPLE® drywall where recommended.

For a standard size room (approximately 12’ x 16’ x 8’), the average difference in material cost to upgrade to PURPLE® products is:

  • $50 or less for XP® drywall (including ceiling)
  • $200 or less for Hi-Abuse® XP® or Hi-Impact® XP® drywall
  • $175 or less for SoundBreak® XP® drywall (per wall)

Prices vary by region. Check with your local home improvement store or contractor for prices and availability near you.

Traditional green drywall (also known as greenboard) is only moisture-resistant. PURPLE® drywall, only made by National Gypsum, is superior because it offers moisture, mold and mildew resistance.

In addition, many PURPLE® drywall products offer added benefits, including resistance to scratches, scuffs, dents and sound.

PURPLE® drywall is made of a specially treated, moisture- and fire-resistant gypsum core. That core is sandwiched between heavy, moisture-, mold- and mildew-resistant, 100 percent recycled paper that’s purple on the front and gray on the back.

While there’s no such thing as completely soundproof drywall, by installing SoundBreak® XP® Drywall or adding SoundBreak XP Retrofit® Board to existing drywall you can drastically reduce the amount of noise you hear between rooms from music, television, conversation, a baby crying or dogs barking.

At the center of SoundBreak® XP® drywall products is a layer of material specifically designed to absorb and dissipate noise. That material, called a polymer, is sandwiched between two pieces of high-density, mold-resistant drywall and covered by heavy, moisture-, mold- and mildew-resistant, 100 percent recycled purple paper on both sides.

Want to hear the difference? Check out our SoundBreak® XP® demo.

Hi-Abuse® XP® Drywall features a heavy, abrasion-resistant face paper and a specially formulated core to provide greater resistance to surface abuse, such as scuffs from shoes and backpacks in the mud room or scrapes from carrying heavy luggage up and down a stairwell.

Hi-Impact® XP® Drywall features all of the benefits of Hi-Abuse® XP® Drywall plus a fiberglass mesh embedded into the back of the board to prevent accidental holes from car doors or bike handles in the garage or a hole from a doorknob or pool cue in a playroom.

Gypsum itself is naturally fire-resistant. Gypsum drywall is made by sandwiching a core of wet plaster between two sheets of paper. When the core sets and dries, the sandwich becomes a strong, rigid, fire-resistant building material. It’s resistant to fire because in its natural state, gypsum contains water; and when exposed to heat or flame, this water is released as steam, which delays heat transfer.

No. PURPLE® drywall installs, finishes and decorates like standard drywall.

This is the highest standard for indoor air quality. To achieve it, National Gypsum’s products have passed rigorous third-party sample testing and review of manufacturing processes with strict standards set by GREENGUARD Certification, part of UL Environment. GREENGUARD certifies products and materials for low chemical emissions and provides a resource for choosing healthier products and materials for indoor environments. All certified products must meet stringent chemical emissions standards based on established criteria from key public health agencies.

Installing & Finishing Drywall (14)

You can do either. With the right tools, precision and patience, cutting and hanging drywall is definitely doable for a do-it-yourselfer. Taping and finishing are the tricky parts. Some people hang the panels themselves or with the help of a friend, and then hire someone to finish the job.

Visit our Installation Tips page for step-by-step instructions available both as videos and printable PDFs.

Your drywall needs likely differ from room to room.

For example, while standard drywall is likely appropriate for a low-traffic, low-activity area like a dining room, XP® Drywall is a better choice for areas prone to moisture such as bathrooms and basements. Use SoundBreak® XP® Drywall in rooms where sound traveling in or out is a concern, and Hi-Abuse® XP® Drywall and Hi-Impact® XP® Drywall in busy or rough-and-tumble areas like mud rooms and playrooms or high-traffic areas like hallways and stairwells.

Check out our Projects pages for more specific recommendations on the best PURPLE® products for each room, or ask your contractor or local home improvement store.

Use our Materials Calculator to determine how much drywall you’ll need for your next project. All you need to know are your room’s dimensions. The calculator will do the rest.

You can also get in-person help at your local home improvement store or ask your contractor.

Watch our drywall installation how-to video:
Measuring & Estimating

Our Materials Calculator will tell you not only how much drywall you need, but other tools and supplies to have on hand as well, such as nails, screws, joint compound, drywall tape, sandpaper and knives.

This process involves measuring, cutting, hanging, taping the seams, applying three coats of joint compound (also called mud), installing corner bead and trim, and then priming your new drywall surfaces for painting.

Visit our Installation Tips page for step-by-step instructions available both as videos and printable PDFs.

Always hang PURPLE® drywall with the purple side out, or facing into the room. It decorates like standard drywall, which means the purple won’t be visible under white or lightly colored paint.

Set your sheets of drywall upright with the smooth side out. Put your T-square on the top edge on one sheet and line it up with your measurement. Score your cut by running a utility knife along the side of the “T.” Snap the sheet back to break the sheet along the cut. Use a utility knife to cut the paper back. To cut around obstacles, use a drywall saw like you would any hand saw. Cut around electrical boxes with a keyhole saw. Punch the tip of the saw through the drywall and cut along each side. A power jigsaw also will work.

Watch our drywall installation how-to videos:
Cutting & Scoring the Board
Cutting for an Electrical Box

Nails require only a hammer and cost less than screws. Screws need power tools, but you use fewer of them and they hold more securely. Screws provide a cleaner look, are easier to countersink and hide with joint compound, remove more easily and don’t require pounding, which can take its toll on the structural integrity of the wall.

Three. First, a bed coat to cover the seams between panels of drywall, fill in “dimples” from fasteners such as nails or screws and hold drywall tape; then a block coat to spread on top of drywall tape to seal it in place; and finally a finish coat to make your new walls and ceilings look as smooth and even as possible.

Watch our drywall installation how-to videos:
Mixing & Applying Joint Compound
Applying the Second Coat of Joint Compound
Applying the Final Coat of Joint Compound

Drive a new nail 1.5” above the popped nail into the stud – indent the face paper without tearing (called “dimpling”). Drive and “dimple” the popped nail. Cover with a thin, uniform layer of joint compound and let it dry for 24 hours.

Yes. Use either 1/2” or 5/8” thick panels. Run the long length of the drywall panels perpendicular to your framing.

Watch our drywall installation how-to videos:
How to Hang Ceilings
Securing the Ceiling with Fasteners

To cut around such obstacles, use a drywall saw like you would any hand saw. Always use proper electrical safety precautions when working around wiring.

Watch our drywall installation how-to video:
Cutting for an Electrical Box

Instead of drywall, use PermaBase® Cement Board behind tile in showers and tubs. Because it’s specially designed for the wet areas in bathrooms and kitchens, it’s hard, durable, naturally moisture- and mold-resistant, and won’t rot, disintegrate or swell when exposed to water.

Use PermaBase® Cement Board instead of drywall under tile in the kitchen or bathroom. It’s hard, durable, naturally moisture- and mold-resistant, and won’t rot, disintegrate or swell when exposed to water, making it ideal for use behind ceramic tile, backsplashes and countertops.