Square set and shadowline
The junction with no cornice on it at all: flush square set, and recessed shadow details formed with a bead.
Square setCornice
Cornice installation and repairs in Sydney, matched so the run reads continuous
Cove and decorative cornice fitted to new work, damaged lengths pieced in, and old runs matched so the join stops being the first thing you see when you walk in.
Cornice is a length of profiled plaster doing two jobs at once. It closes the junction between two surfaces that will never be perfectly square to each other, and it gives the room a line that carries the eye around it. When it is right you do not notice it. When it is wrong you notice nothing else.
So most of a cornice job is not the fixing. It is the measuring, the profile match and the corners. Get those settled and the rest is a day of careful work. Get them wrong and no amount of compound will hide a mitre that does not line up.
- Cove and decorative profiles
- Quoted by the lineal metre
- Pieced into existing runs
Priced by the metre
A cornice quote is a length, a profile and a corner count, not a guess at the size of the room.
Profile settled first
What you already have, or what the room can carry, gets decided before anything is ordered.
Corners cut, not filled
Internal and external mitres cut to fit so the line carries around without a bump at the change.
Repaired where it can be
A damaged length usually comes out on its own. The rest of the run stays exactly where it is.
Know what you have
Cove, stepped or ornamental: reading the profile in front of you
Most Sydney rooms carry one of a handful of profiles. Working out which one you are looking at decides whether a damaged section can be matched from stock, matched approximately, or has to be made.
| Profile | Where it usually turns up | What it means for the job |
|---|---|---|
| Plain cove, the common sizes | Project homes, unit blocks and most renovation work from the 1970s onwards | A stock item in several girths. A replacement length is matched by measuring the face and the two lines it sits against. |
| Stepped and banded profiles | Renovations chasing a sharper line than a plain cove gives | The flat faces catch light along their whole length, so the wall and the ceiling have to be straighter than a cove would forgive. |
| Colonial and Federation profiles | Terraces, semis and cottages through the inner and middle ring | Sometimes still available as a run, sometimes not. Where it is not, you choose between the closest stock match and having the section replicated. |
| Enriched and ornamental plaster | Grand older rooms, usually with a ceiling rose that belongs to the same scheme | Matching a moulded enrichment is a different craft and sits on the restoration page, not here. |
| No cornice at all | Contemporary builds and renovations using a flush or a recessed junction | There is nothing to match. The junction is formed in the set instead, which is square set and shadowline work. |
Reading the damage
Where a cornice run actually lets go
Cornice almost never fails along its whole length. It fails at the joins, at the corners, and wherever something behind it moved. Each of those is a different amount of work, and from the floor they can look identical.
The most common fault is a fine line along the top or the bottom edge of the cornice rather than in the cornice itself. That is the junction opening, not the profile failing. The cornice and the sheet either side of it move at slightly different rates as the building warms and cools, and the thin band of compound along the edge is the first thing to give. It is raked out, reinforced and re-set, and the cornice itself is left alone.
The second is a corner that has opened. A mitre carries two lengths into each other at an angle, and any movement at all shows up there first because that is where the profile changes direction. A hairline at a mitre is normal work. A mitre that has stepped, where one length now sits proud of the other, means something has dropped and it gets refixed before it is re-set.
The third is a section that has come away from the wall or the ceiling and is hanging on the paint. You can usually find it by running a hand along the run and feeling for a length that gives. That section comes off, the surfaces behind it are cleaned back, and it goes up again with mechanical fixing as well as adhesive.
Scope
What cornice work covers on this page
This page owns the projecting cornice: supplying and fitting it, repairing it, replacing it and matching it into what is already there. The junctions that carry no cornice at all, and the ornamental work that has to be replicated rather than bought, have their own pages.
What this covers
- New cornice run through a single room or a whole house, cut, fixed and set
- Damaged lengths cut out and pieced in, with the joins set flush into the run
- A full run taken off and replaced where it has been patched too many times
- Internal and external mitres, including bay windows, angled walls and returns
- Cornice refixed where a length has dropped away from the wall or the ceiling
- An existing profile matched as closely as the available stock allows, with the limits explained before you commit
- Cornice reinstated after a ceiling has been re-sheeted or a wall has been lined
- The cornice line and the two edges either side of it set, sanded and left paint ready
What this is not
- A wall and ceiling meeting with no cornice at all, which is square set and shadowline
- Replicating enriched mouldings, ceiling roses and ornamental profiles, which is ornate and heritage restoration
- Cracking out in the ceiling plane away from the cornice line, which is ceiling repairs
- A boxed drop, a curtain recess or a pelmet the cornice then runs along, which is bulkheads and pelmets
- Timber cornice, moulded skirting and architraves, which is carpentry rather than plastering
- Painting the finished run, which your painter does once the compound has dried right through
If the profile you have cannot be bought any more, you will hear that at the quote along with the two honest options, rather than finding out when a length arrives that nearly matches. Where a length has been pieced into an existing run, plan on repainting the whole run: fresh compound and aged paint will not match however flat the join is.
Before you ring
What we need in order to price a run
Cornice is one of the easier things to quote accurately from a distance, as long as we get the right few pieces of information. Most of it you can gather in five minutes with a phone and a tape.
- A photograph taken square on to the cornice, close enough that the shape of the profile reads
- A second photograph from further back showing the whole wall and ceiling line
- Rough lineal metres, or the room dimensions we can add up ourselves
- How many internal corners, and how many external ones, because they are not the same work
- Ceiling height, and whether there is a stair void, a raked ceiling or a double-height entry in the run
- Whether the walls and ceilings are already set, or the job is still to be sheeted
- Whether any existing cornice is staying, and where the new work has to meet it
- Whether the room is furnished, tenanted, or still an open site
How the job runs
Measure the run, match the profile, cut the corners, fix, then set
A cornice job is front-loaded. Nearly everything that decides whether it looks right happens before a length goes up, which is why the measuring and the ordering get more attention than people expect.
- 01
Measure the run, not the room
Every wall is measured along the line the cornice will actually follow, then the corners are counted separately. Offcuts are part of the calculation, because a mitre eats length and a short piece in the middle of a wall is a join you did not need.
- 02
Match or choose the profile
On a repair, the existing profile is measured and photographed and checked against what can still be bought. On new work, the profile is chosen against the ceiling height and the rest of the house, so one room does not sit oddly against the next.
- 03
Prepare the two surfaces
The cornice needs something straight and clean to sit against. High spots come off, loose paint and old adhesive come back to a sound surface, and anything that will stop the cement grabbing is dealt with first.
- 04
Cut the corners first
The internals and externals are cut and fitted before the straight lengths get their final cut, because a corner that is a degree out has to be absorbed somewhere and it is easier in the middle of a wall than at the change of direction.
- 05
Fix it, then hold it
Cornice cement along both contact faces, pressed home to the set-out line, with mechanical fixing where the length is heavy, the run is long, or the surface behind it is not something adhesive can be trusted to.
- 06
Set the joins and both edges
The mitres and the butt joins are filled and worked until they read as one continuous profile, then the top and bottom edges are set and sanded. That is the part that decides whether anyone can see where one length stopped and the next began.
Set-out and supply Fix and finish
The quote
What a cornice price is built from
Two runs of the same length can be very different jobs. These are the things that actually move the number, roughly in the order they tend to matter.
Lineal metres
The base of every cornice quote. It is the length of the run, measured along the walls it follows, not the floor area of the room.
The profile and its girth
A plain cove in a common size is the cheapest thing on the list. A deep or stepped profile costs more per metre, handles heavier, and takes longer to set.
How many corners
Corners are where the time goes. A long straight hallway run is quick per metre. A room with a bay window, an angled wall and three returns is the same metres and a much longer day.
Whether it is new work or a repair
Running cornice onto freshly set walls is the straightforward case. Cutting a length out of an existing run, matching it and making both joins disappear takes longer per metre than running a whole fresh wall.
How straight the surfaces are
Cornice hides a small amount of difference between a wall and a ceiling and no more. Where the wall bellies or the ceiling dips, that has to be brought in first or the cornice will telegraph it.
Height and access
A run you can reach off a pair of trestles is one rate. A stair void, a raked ceiling or a high entry needs staging, a second person for the long lengths, and more time to do the same metres.
Whether the profile is still available
A stock match is straightforward. Where the profile has been out of production for decades, the options are a close match or replication, and those are different prices.
Protection and clean-up
An empty room before the floors go in is quick. A furnished living room, a tenanted unit or a shop still trading changes how the work is staged and how much of the day goes on covering up.
Before it goes up
Ordinary cornice work, and what to settle first
Cornice is the last thing to go on and it gets blamed for everything that happened before it. Most runs are simply a run. A few need a question answered before anyone orders material.
Straightforward cornice work
- A new room, walls and ceiling set, ready for a run to go on
- A hairline along the top or bottom edge of an otherwise sound run
- One or two damaged lengths in a profile that is still available
- A mitre that has opened slightly without stepping
- A section that has let go of the wall and needs refixing and re-setting
- Cornice reinstated after part of a ceiling has been re-sheeted
- A run taken off, the wall straightened, and a new run put up in its place
Get this answered before the cornice goes on
- Cracking that runs on through the wall below, or through brickwork, rather than stopping at the cornice
- A cornice line that has opened in the same place twice after being properly repaired
- Any sign of water above the run: a stain with an edge to it, or plaster that feels soft
- A ceiling that has dropped away from the frame, which has to be dealt with as sagging before a cornice line means anything
- Enriched or moulded work that someone has already tried to repair with a general filler
- Doors or windows that have started sticking at the same time as the cornice opened
Either side of the job
Where the cornice line meets the rest of the work
Cornice usually arrives at the end of something else, or instead of something else. These four are the pages it hands over to most often.
Ornate and heritage plaster
Enriched profiles, ceiling roses and moulded detail that has to be replicated rather than bought by the length.
RestorationCeiling replacement
When the ceiling comes out, the cornice usually comes with it. The run is reinstated once the new sheet is up and set.
ReplacementBulkheads and pelmets
Boxed drops and curtain recesses, which change where the cornice run starts, stops and turns.
BulkheadsQuestions
Cornice questions we get asked most
If yours is not here, ask it. We would rather answer it on the phone than have you guess.
Can you match the cornice I already have?
Usually, and the answer comes from a photograph taken square on plus a measurement across the face of the profile. Plain and deep coves in the common girths are stock items, so a replacement length is a straightforward match. A number of the older Sydney profiles are still produced as well.
Where it cannot be matched from stock, there are two honest paths and we will put both to you. Either the closest available profile goes in, which is often acceptable in a room where the new work is not next to the old, or the section is replicated, which is restoration work and priced accordingly. What we will not do is fit something that nearly matches into the middle of an original run and leave you to discover it.
How is cornice quoted?
By the lineal metre of run, with the corner count and the profile as the two things that adjust it. That is why we ask for room sizes or a rough metre figure rather than a floor area: a long thin hallway and a square room of the same floor size carry very different lengths of cornice.
On a repair the metres matter less and the joins matter more. Cutting one length out of a run, matching it and setting both joins invisibly takes longer per metre than running a whole fresh wall, so short repairs carry a minimum rather than a metre rate.
There is a crack along the top of my cornice. Is that the cornice or the ceiling?
Nine times in ten it is the junction rather than either surface. The cornice is fixed to the wall and the ceiling, and those two move independently with seasonal change in the frame. The thinnest material in the whole assembly is the band of compound along the cornice edge, so that is what opens first.
It is raked out, reinforced and re-set, and the cornice itself is not touched. What is worth watching for is a crack that has opened in the same place after a proper repair, or one that carries on down the wall past the cornice. That is movement in the structure rather than a finishing fault, and it wants understanding before anyone fills it again.
Can one damaged length be replaced without redoing the whole room?
Yes, and that is normally the right answer. The damaged section is cut back to a clean line at both ends, ideally at a point where the join will fall somewhere the eye does not naturally rest, and a new length is fitted and set into the existing run.
Two things make it harder. One is a profile that is no longer available, which turns a piecing-in job into a matching decision. The other is a run that has already been patched several times at slightly different levels, because each of those old joins reads as a shadow under a wall light. At that point taking the run off and starting again often costs less than chasing it length by length.
Is cornice glued on, or screwed?
Cornice cement does most of the holding on a normal run. It is applied to both contact faces, the length is pressed home to the set-out line, and the cement grabs while the joins are being filled. Done onto sound, clean, straight surfaces it holds for the life of the building.
Mechanical fixing goes in as well where the length is heavy, the run is long, the surface behind it cannot be trusted, or the cornice is going back onto something that has already let go once. Deep profiles in particular want holding while the cement takes, which is part of why they cost more per metre to run.
Should I keep cornice in a renovation, or go without it?
It depends on the house and on how much you want to spend on the surfaces behind it. Cornice is forgiving: it closes the junction and absorbs a small amount of difference between a wall and a ceiling. Going without means the junction itself becomes the finish, and everything behind it has to be straighter.
That cornice-free junction is its own job with its own set-out and its own tolerances, and it is covered on the square set and shadowline page. In an older house with walls that are nowhere near plumb, cornice is very often the sensible answer even when the look you want is the other one.
Get a number
Send a photo of the profile and the metres
One picture square on to the cornice, one from further back, and a rough length. That is usually enough to tell you whether it can be matched and what the run will cost.