Gypsum wallboard, commonly known as drywall, is the most popular material in the U.S. for interior walls and ceilings due to its versatility, durability, and ease of installation. Whether you're a seasoned remodeler or a first-time DIY’er looking to take on an improvement project, installing drywall can be a rewarding task but a tricky one to master. Even professionals with experience hanging drywall often struggle with finishing the joints, which is a skill that requires a lot of practice to get perfect. This guide will walk you through an overview of installing drywall, providing real-world guidance on the challenges you’ll face.
Materials: Drywall panels (gypsum wallboard sheets), joint compound, drywall screws, joint tape, corner bead, primer/sealer, paint
Tools: Screw gun or drill, T-square, utility knife, drywall saw, joint knife, sandpaper, mud pa, drywall rasp, drywall lift, (optional for ceiling installation)
Prep Steps
Carefully measure the dimensions of your walls and ceilings, noting any openings for doors, windows, and outlets. Plan the layout to economize drywall panel usage and minimize waste. When calculating the number of 4x8-ft. or 4x12-ft. drywall panels, order about 10 percent more panels for the project to account for waste.
Make sure you plan for all the necessary tools and materials, including drywall panels, drywall tape, corner beads, screws, joint compound, tape measure, utility knife, T-square, and screw gun.
Are you installing panels on the ceiling as well as the walls? Drywall sheets on residential walls are usually 1/2-in. thick, whereas the ceiling drywall is usually 5/8-in. thick to reduce the issue of the panels sagging between ceiling joists.
Are you installing drywall in the bathroom? If so, consider using “greenboard,” which is a generic term for water-resistant drywall panels approved for use in damp areas. Widely used as a wall surface in high-humidity spaces, such as bathrooms and laundry rooms, the greenboard’s paper facing has been treated with a waxy coating and chemicals to resist moisture and mildew.
Store the panels in a dry, sheltered area while you clear the site. Remove any obstacles from the work area to create a clutter-free space. Cover floors and furniture with drop cloths or plastic sheets to protect them from dust and debris.
Before installation, inspect the framing of the walls and ceilings. Address any issues like water damage or warped studs to ensure a solid, flat foundation for your drywall. For fixtures like towel bars, handrails or cabinets, install 2x4 wood blocking between the studs to provide a secure anchor point for the fixtures after installation.
Ensure all electrical and plumbing work is completed before installing drywall. You will have to make cutouts for the outlets. Exterior walls should have insulation between the wall studs.
Mark all stud locations on the floor and ceiling to help guide the attachment of drywall
panels. Plan the placement of drywall seams to minimize visible joints. The 4x8-ft. panels can be installed horizontally or vertically. Staggering the seams between adjacent panels will achieve a stronger wall and smoother finish.
Note that the eye tends to notice vertical joints easier than horizontal joints, so pro installers often hang the panels horizontally to minimize the number of vertical joints.
The electrical and plumbing work should be completed in the walls before drywall installation, and you will need to cut out all penetrations.
Cutting Drywall
Use a measuring tape to determine the length and width you need for the drywall panels. Mark these measurements on the wallboard with a pencil. For straight cuts, use a straightedge or T-square to ensure accuracy.
If you're making a straight cut, place the long arm of the T-square along the marks and hold it firmly. Use it to guide a sharp utility knife and score the drywall along the cutline. Apply firm and consistent pressure while cutting through the paper surface and into the gypsum core. Repeat the scoring process until you see a visible groove. For curved cuts or openings, use a flexible curve or template to mark the shape onto the wallboard, and then follow the same scoring technique.
After scoring, gently lift the wallboard along the cut line and snap it along the groove. Use the edge of a table or another flat surface to support the wallboard as you snap it. The goal
is to break the gypsum core cleanly along the scored line.
Once the wallboard is snapped, use the utility knife to cut through the paper facing on the backside of the break for a clean and precise edge.
To refine the cut edges, use a rasp or sanding block to smooth any irregularities.
Oscillating tools are handy for making small cut-outs, but the use of powered cutting tools should generally be avoided for drywall due to the large amount of dust and mess they generate.
To cut drywall, first measure and mark the cut line. Use a sharp knife to score the paper face with a sharp utility knife and snap the gypsum core along the score line. This method maintains accuracy and minimizes airborne dust.
The square cross-brace of a T-square helps it to hold position when you score along its straight-edge with a utility knife.
A drywall rasp is a handy tool for smoothing out any rough edges on the drywall sheets.
Hanging the Panels
Carefully measure and cut the drywall sheets to fit the dimensions of your walls or ceiling. If you encounter outlets or switches, use a drywall saw to cut openings for them.
Attach the panels to the studs using drywall screws and a powered driver. Position the panels with their tapered edges facing each other (which makes it easier to embed tape at the joints). Leave a 1/8-inch gap between the sheets for expansion. Space the screws approximately 12 inches apart along the studs.
If you're working on ceilings, you’ll need to rent a drywall lift to raise and hold the sheets in place. Start at one corner and attach the drywall sheets to the ceiling joists using drywall screws. Ensure the edges of the sheets meet the center of the joists.
When hanging sheets on walls, begin at one corner and work your way across the room. Secure the drywall sheets to the studs with screws and stagger the seams between sheets for a more stable wall.
Hang the drywall sheets with 1/8” expansion gap between them. The best practice is to set the torque of your power driver to countersink the screws slightly below the drywall surface without tearing the paper face.
At an outside corner, lap one sheet of drywall over the edge of the other and fasten it to the stud. If the end of the lapped sheet extends past the other wall, rasp away the excess material.
In some cases, a drywall panel may meet a corner stud that can only support an adjacent panel. In this case, use a metal drywall corner clip to support the panel edge. One side of the clip holds the panel, and the other has a tab which connects to the stud.
Taping and Finishing
In a nutshell, all the drywall joints between panels should be taped and finished with
joint compound. Although that sounds simple, finishing drywall with a professional appearance takes a skillful approach and patience from the inexperienced installer.
Drywall tape is available in paper varieties, perforated varieties (to reduce blisters), fiberglass mesh, and moisture-resistant varieties.
Drywall taping knives are the essential tools for finishing the walls. You’ll need a 4-,
6- and 10-inch knife. A 14-inch finishing trowel also helps to smooth the joints. Another handy item for the mudding phase is called a “hawk,” which is a small flat pan for carrying joint compound (AKA drywall mud).
Use a 4-inch knife to cover fastener heads and to lay a thin layer of mud over the joints in which to embed the joint tape. Use the same knife to press the tape into the mud and even out the edges.
In general, drywall tape is embedded along the joints in a thin coat of joint compound.
Wall corners get special treatment. Some drywall tapes include a crease along its midpoint, which makes it easier to fold in half lengthwise and fit into an inside corner.
Outside corners should be protected with a corner bead, which are the long, rigid strips
that wrap intersecting walls with an L-shaped profile. You can use metal or rigid vinyl corner beads in square or bullnose shapes (for rounded corners). Cut the corner bead to length with tin snips, keeping its bottom end about 1/2 inch off the floor. Lightly press on the corner of the bead, squaring the strip against the walls. Drive a few nails or staples through the corner bead to establish its position, then nail it for a stronger hold. Space the nails about 8 inches apart. Use a 6-inch drywall knife to apply the first coat of mud to the corner. The knife glides along the raised corner bead and the wall, laying the compound in the valley between the two high points.
Outside corners are protected with vinyl or metal corner bead, which are rigid strips fastened over the drywall and then coated with joint compound.
Always allow the first coat compound to dry completely before recoating.
Before applying the second coat of compound, use a scraper to remove any ridges or chunks in the dried mud. Then, use the 6-in. knife to apply a coat of compound over the taped joints. Next, use a 10- or 14-in. knife held almost flat against the wall to smooth out the mud at the seams. Don’t worry about achieving a perfect finish, just fill the seams while minimizing the need to sand. Aim for a flat and smooth application but remember that you can sand away imperfections once the second coat has dried.
Pro tip for inside corners: After the tape has dried into the first coat, mud over only one side of the inside corner tape at a time, allowing the first side to harden before covering the
second side.
Because joint compound generally shrinks as it dries, it’s common to find screw indentions where you’ve coated the fasteners. Give these visible dimples another coat of compound when applying the second coat to the joints.
Ideally, you’ll only need one last coat to finish the walls. For the final coat, use a wide drywall knife to feather-out the compound as smooth as possible, allow to dry and sand well.
The key to success lies in how well the panels are finished to disguise the joints. A poorly finished wall surface with high crowns of accumulated mud may reveal visible joints that are uneven with the wall. This is why it’s so important to feather the edges into a smooth transition. It takes a bit of finesse with the drywall knife, but a DIY’er can succeed with practice and patience.
Sand and Finish
Once the final coat is dry, use a sanding block with fine-grit sandpaper to smooth the surface. Feather the edges to create a seamless finish.
Be cautious not to over-sand (a common DIY mistake), because it can expose the tape and
create an uneven surface. If you expose the tape, then it’s back to square one when you reapply and feather out the mud in successive coats, sanding to achieve a smooth finish free of any blemishes.
Joint compound tends to shrink when it dries, so expect to fill screw holes and similar imperfections with at least two coats. Sand between coats to knock down high spots and help feather the edges of the joint compound.
Note that sanding the dried joint compound creates a lot of dust, so sealing off the surrounding rooms from airborne exposure is always a good way to keep the house tidy. Be sure to wear a dust mask when sanding. Another trick is to use a damp drywall sponge in the final phases, which can help melt and wipe away high spots without the abrasion that creates so much dust.
For the final coat, use a wide drywall knife to feather-out the compound as smooth as possible, blending the joint with the surrounding wall.
Pro tip: Since texture and porosity differences between the mudded joints and paper-faced
drywall can lead to a mismatched paint finish (especially in areas exposed to a lot of light), some professional drywallers give the entire wall surface a skim coat. This is a thin coat of drywall mud that leaves a film thick enough to fill imperfections in the wall and provide a uniform surface for priming. In any case, it is always important to seal new drywall with a quality primer/sealer prior to painting the walls your choice of color.
Take your time with drywall work, follow each step carefully, and you'll soon have walls that showcase a professional touch.
Editor's Note: Special thanks to Caleb and Randy Stephenson of Core Resources in Birmingham, Alabama, for help with this article. You can reach Core Resources at (205) 612-9021.
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