A beginner's guide to drywall installation
[Guest post from Next Step Construction]
An edited transcript of the video:
Install the ceilings first. The walls should support the edges of the ceiling panels to prevent cracks as the building settles and/or shifts with heavy wind pressure.
- Cut panel to length so that the end lands in a framing member. To support the joint.
[Editor's note: floating the butt seams between framing members is another way to do it—strategic use of a backer strip can actually pull the seam up, allowing a tapered joint when applying mud.]
- When cutting sheets, cut the end that will but the outside wall rather than the edge that will make the butt seam.
- Mark the length and slide a T-square along the top of the sheet to the mark.
- Use your foot to anchor the bottom of the square while you run a utility knife down the square edge to score the paper face, cutting about 1/8 inch deep I to the gypsum core.
- Fold the cut back, score the back paper facing, and snap the cut forward.
- Use a drywall rasp to smooth the cut edge.
Measure for the light boxes
- One way to do it is to measure to the center of the light box, hang the drywall over the box and cut the hole with a router.
- Another way to do it is to measure exactly where the box is, add 1/8 inch to the size, cut the hole and then hang the sheet. This is the method illustrated in the video. Measure from two perpendicular walls that can be transferred to the sheet.
- When transferring these numbers to the sheet that is still leaning against the wall, make sure to visualize how the sheet will lie on the ceiling—if you pull from the wrong edge, you just bought a sheet of drywall with a hole in it. And a little jobsite ribbing, too.
- Use the T-square to mark the four measurements, making a square where the circle will be.
- Draw a circle inside the box using a compass. If you do not have a compass, or you do not feel like walking to the truck to rummage around for it, make one with a scrap of the paper edging that holds the two sheets together.
- Poke a screw through one end of a paper scrap, poke the screw into the center of the box (draw diagonal lines to find center). Make a hole for your pencil at the appropriate radius, and draw a circle.
- Use a keyhole saw to cut the drywall.
Hang the ceiling sheets
- Before raising the sheet to the ceiling, mark the ceiling joists on the wall plates
- Professional drywalls use two people to raise and fasten the sheets. When working with volunteers, it is wise to use two people to hold the sheet, and one or two more to fasten.
- It may also make sense to have an extra person to act as a spotter from the ground to make sure that the sheet is landing where it needs to before screws go in.
- With one person on each end, roll the sheet up, step up into your ladder or benches, and push it tight to the ceiling.
- Make sure the sheet is tight to the walls and that the hole fits over the light box, and "throw a few screws in it. "
- With a few screws in one end, drive a few into the other end to take a load off your buddy. Unless you want to punish your buddy, then drop your screws, pretend the battery is dead, and stop to tie your shoe.
Screw off the sheet
- With screws in either end, pause to make sure the sheet is indeed where you want it. And that the sheet is tight to the ceiling framing everywhere. Like in the corners.
- Because you cannot suck a sheet tight to the framing with screws, you need to push it tight. Professionals use their heads. Hard hats make this easier.
- Screw depth matters, too, the head should be driven slightly beyond the face of the drywall without tearing the paper.
- Buy a drywall dimpler to reduce the chances of driving screws too deep.
- Use a straight edge to mark the ceiling joists across the sheet so that fewer screws will miss. You can also do this in the ground using the T-square after you cut the sheet to length.
- Screw of the sheet aiming for five screws in each ceiling joist. This is done by putting one screw at each edge, one in the middle, and splitting the two spans.
- Professional drywalls often use four screws: at the beginning and then at 16 in intervals. Fewer screws reduces the chance if screw pops.
- As added 'insurance for volunteers, they suggest adding a second screw next to each existing screw—in case one breaks the paper.
- But do not screw into the factory edge yet—wait until the abutting sheet is in place. Otherwise you may break the edge, making it harder to fit the next sheet and tape the seam.
Finish the row before hanging sheets for the second one
- To finish the run, measure the length of the second sheet. Measure both ends of the opening you need to fill—because sometimes things are not square. Really.
- Cut the panel to be about 1/8 inch shorter than the smaller number. You do not have to be perfectly tight because the wall panels will butt the ceiling, burying 1/2 inch if ceiling panel.
- Again, measure from the factory edge that will butt the other sheet.
- Have your volunteer climb the ladder and hand them their end. Factory edge slides in first, tight, and the cut end slides up the wall to lay tight against the ceiling framing.
- Before screwing anything in pace, make sure the back edge, the long one which will butt the next course of drywall, is straight. Otherwise: gaps.
- Make sure the butt seam is tight and that the sheet is tight to the ceiling on all the edges. In his case, the plastic is bunched up, preventing the sheet from laying tightly against the framing in one corner of the sheet.
- If you must, cut the plastic to relieve the bunching, and then tape it back together again.
[Editor's Note: This is important. Plastic vapor barriers are a gamble as it is, cutting holes in them tilts the odds way out of your favor in the fight against house rot.
Because a boatload of moist air can flow through the same small hole that a thimble full of vapor will diffuse through. ]
- Reinstall the panel, making sure the seam and leading edge are tight and straight.
- Screw it.
Hanging drywall with the finisher in mind
- A note about seams for the uninitiated: the long edges are tapered. The short edges are not. The taper makes taping easier, the untalented edges make it more difficult.
- It is very important to get the seams and edges right in the first row. Because: compounding errors.
- Stagger the sheets, do not line up the seams and you will get a better finish.
- With all the sheets up, and the seams tight, it is safe to screw off the butt seams — every six inches is the recommendation, but remember: more screws means more opportunity for screw pops.
—Next Step Ministries is a 501c3 non-profit organization committed to helping students grow closer to Christ through challenging construction projects. The Construction Department understood that putting volunteers and staff on construction projects without the proper training was not helping anyone. This video series is meant to help train those who are interested in learning more about construction and using those skills to serve alongside a community in need.