Hanging
Hanging drywall: ceilings first, then walls, and why
Every hanger does the ceiling first. The reason is structural, not habit, and the same logic decides the order of every row on the walls.
Why the ceiling goes first
The ceiling sheets are hung first and pushed tight against the top plates of the walls. The wall sheets then go up underneath, with the top row pushed up against the ceiling board. That way the wall board supports the edges of the ceiling board, and the inside corner where they meet is a clean, tight line for the tape. Hung the other way round, the ceiling edge would sit on nothing but its screws, with a gap above the wall board that is hard to tape and quick to crack.
The same reasoning sets the order on the walls: top row first, tight to the ceiling, then the bottom row, cut to fill the gap at the floor, where the baseboard will cover the cut edge.
Before the first sheet
- Inspections done. Framing, insulation, electrical and plumbing inspections usually come before the board. Many jurisdictions also inspect the screwing on fire-rated walls before taping.
- Mark the joists. Pencil the centre of every joist on the top plates, so you can find them through the board.
- Blocking in place. Backing for cabinets, grab bars, curtain rods and the edges of the ceiling where joists run parallel to a wall.
- Insulation and vapour control done, as your climate and code require.
- Board in the room, ceiling sheets on top of the stack.
Hanging a ceiling
Ceiling sheets run across the joists, long edges perpendicular to them, so each sheet is held by every joist it crosses. Start in a corner with a full sheet, its end landing on the centre of a joist; cut the last sheet in the row to land on a joist too. Start the next row with a sheet cut so its butt joint falls at least one joist away from the butt joint in the row before.
Screws go at 12 in on ceilings, under GA-216, against 16 in on walls. The guide to screws per sheet has the full table.
A 14 × 12 ft ceiling, joists at 16 in
- 168 sq ft; 4 × 8 sheets: 168 ÷ 32 × 1.1 = 5.8, so 6 sheets, 210 screws
- In 4 × 12 sheets: 4 sheets, 200 screws
- Either way about 307 lb of 1/2 in board overhead
- Joints to tape: 92 ft, of which 52 ft is the angle where the ceiling meets the walls
The ceiling drywall calculator counts the sheets and checks the thickness: on joists 24 in apart, 5/8 in or sag-resistant 1/2 in board.
Getting the sheets up there
A 4 × 8 sheet of 1/2 in board weighs about 51 lb and a 4 × 12 about 77 lb. Held overhead for the time it takes to drive the first dozen screws, that is a two-person job at least.
- A panel lift raises a sheet on a cradle to the joists and holds it there. It turns ceilings into a one-person job and is the safest method; rental shops rent them by the day. The delivery and lift planner counts the days.
- Two people and a T-brace: one or two 2 × 4 tees cut about 1 in longer than the ceiling height wedge the sheet up while it is screwed.
- Lightweight board, at about 40 lb a 4 × 8 sheet, helps whichever method you use.
Screw the sheet off from the middle out, the first screws in the field rather than the edges, so the board is pulled up flat against the joists.
Then the walls
On an 8 ft wall, two rows of sheets hung horizontally cover the height. Hang the top row first, pushed up tight against the ceiling board, then the bottom row, lifted off the floor with a foot lever so it meets the top row snugly. The gap at the floor, usually 1/2 in, is covered by the baseboard and keeps the board out of any water on the floor.
Stagger the butt joints between the two rows, and keep butt joints away from the corners of doors and windows, where the framing moves. The single wall calculator lays the sheets out on a wall and draws the joints; the guide to sheet sizes and orientation explains when vertical sheets are better.
Corners and openings
- Inside corners: the second sheet butts against the first; the corner is taped, not fastened tight on both sides, to let the framing move. Some hangers leave the first screws back from the corner on one sheet, a floating corner, for the same reason.
- Outside corners: sheets overlap the corner and are trimmed flush; corner bead covers them, counted by the corner bead calculator.
- Doors and windows: hang the sheet across the opening and cut it out with a router or a saw afterwards. Joints should not line up with the edges of the opening.
- Outlets and switches: mark them on the board or use a router with a bit that follows the box.
How long it takes
Our estimates, which the drywall time calculator uses: about a third of a person-hour per 4 × 8 sheet for a professional crew, and about an hour for a careful first-timer, ceilings slower than walls.
40 sheets, two DIYers, Level 4
- Hanging: 40 × 1 h ÷ 2 = 20 h, about 3 working days
- Finishing: four passes, each with a day of drying
- About 9 calendar days from first sheet to sanded walls, 49 hours of work between the two
The hanging is a third of the work. The rest is finishing and, above all, drying, which the guide to drying times between coats covers.
Common mistakes
- Walls before the ceiling. The ceiling edge loses its support.
- Ceiling sheets parallel to the joists. Weaker, and not allowed for 1/2 in board at 24 in.
- Butt joints lined up. Stagger them by a joist or more.
- Board tight to the floor. Leave the gap for the baseboard to cover.
- Ceilings alone. Rent the lift.