How do I take down a lath and plaster ceiling?

A lath and plaster ceiling is thin timber laths nailed across the joists with plaster forced between them, forming nibs that hook over the back of the laths and hold the whole thing up. When those nibs break, the ceiling is held by friction. Taking it down is not technically difficult — it is a question of controlling an enormous quantity of heavy, filthy debris in a confined space, safely.

Safety

What you'll need

• P3 mask, goggles or a full face shield, hard hat, gloves
• A scraper or a lath hammer, and a wrecking bar
• Heavy-duty plastic sheeting and tape
• Rubble sacks — many
• A working platform or trestles and scaffold boards
• Nail bar or pincers
• Torch and a work light
• A dust-rated vacuum (optional)

Step by step

1. Decide honestly whether it needs to come down.Overboarding is faster, cheaper, far cleaner and keeps the acoustic and thermal benefit of the old ceiling. Take it down when most of it has failed, when it is sagging, when the void must be opened for wiring, plumbing or insulation, or when structural work above requires it.
2. Check what is in the void first.Cables, pipes, old insulation, and in some properties, material you should not disturb. Get a torch into the void through an existing hole and look before you commit.
3. Isolate everything electrical in the room and above it.Lighting circuit, any socket circuit routed through the floor above, and any smoke alarm on that ceiling. Old wiring in an old ceiling void is often in poor condition and should be assumed live until proven otherwise at the consumer unit.
4. Empty the room completely and seal it.Everything out. Plastic sheeting taped over the doorway, over any fitted item that cannot move, and over the floor, taped at the edges. Cover radiators. Close doors elsewhere in the house and turn off any ventilation that pulls air out of the room.
5. Get proper access.A working platform, trestles and boards, or a hop-up long enough to work along. A stepladder means constant repositioning while carrying tools and looking upward, which is how people fall.
6. Start at one edge and work backwards.Break into the ceiling at a corner or against a wall, and progress across the room so the material always falls in front of you rather than over your head. Never start in the middle.
7. Take the plaster off first, then the laths.A scraper or a lath hammer pulls the plaster off between the laths. Once a bay is clear of plaster, lever the laths off the joists with a bar. Doing both at once means slabs of plaster still attached to lengths of lath, which is heavy and unpredictable.
8. Clear as you go, in half-filled sacks.Old ceiling debris is extraordinarily heavy. Full sacks split and cannot be lifted. Clear a bay before starting the next, so you are not standing on a rubble pile while working overhead.
9. Pull every nail.Lath nails left in the joists prevent new board sitting flat and are a hazard to hands and knees. Go along each joist with pincers or a nail bar and take them all out.
10. Clean the void and the joists.Vacuum the dust from between the joists with a suitable machine, check the joists for damage, woodworm or old notching, and inspect any cable or pipe that has been revealed. This is the only time you will see it.
11. Do any work in the void now.Wiring, pipework, insulation between the joists, downlight positions, noggins for board edges. Everything is easier now and impossible in a week's time.
12. Re-board, tape or skim.Twelve and a half millimetre board across the joists, joints staggered and landing on joists, noggins under any unsupported edge, then tape and joint or scrim and skim.

Tips

• Hire a skip or bulk bags before you start, and position them for a short carry. The volume from one room's ceiling is much larger than people estimate.
• Damping the ceiling with a garden sprayer before you break it up cuts the airborne dust substantially and costs nothing.
• This is a job where paying someone is often good value: a two-person team will strip and clear a room's ceiling in a day, with the waste taken away, and it is unpleasant work.
• If the ceiling has original cornice, ceiling roses or decorative plasterwork you want to keep, that changes the job completely and needs specialist care — those items are difficult to salvage once the ceiling is coming down around them.

Common mistakes

• Working under the section you are breaking — Slabs of plaster with laths attached come down as a heavy unit, with a century of debris on top of them. Work backwards from an edge so it always falls away from you.
• Not sealing the rest of the house — The dust from a lath and plaster ceiling gets everywhere, and it is fine, gritty and soot-laden. Containment before you start is the difference between a day's cleaning and a fortnight's.
• Leaving the lath nails in — New board will not sit flat, and it is a genuine injury risk while working in the void.
• Taking it down when overboarding would have done — Enormous mess, cost and disruption for a result that boarding over would have achieved in a day.

Questions people ask