How to Paint Coving and Cornice Properly

To paint coving properly, clean it, fill and sand any cracks, prime bare plaster as the maker recommends, then apply thin coats with a good brush, cutting in neatly where the coving meets the wall and ceiling. On ornate cornice, the rule is thin coats and patience, because every heavy coat fills a little more of the detail. If old cornice is already clogged or the paint is flaking, painting over it will not fix the problem, and it may need cleaning back first.

This guide covers preparation, filling cracks, choosing paint, cutting in, painting ornate cornice, when paint build up needs removing, and when removing old coving is the wrong answer. If your cornice needs more than paint, our plaster cornice and coving page explains how we restore and match period profiles.

Preparation and filling cracks

• Protect the room. Clear or cover furniture and floors, and use a stable step or platform so you can work along the coving at arm's length, not overreaching.
• Clean it. Dust and cobwebs collect on the top edge of coving. Brush it down, then wipe with a damp cloth and let it dry.
• Check what you are painting. Tap gently along the run. A hollow sound, loose sections or large cracks mean a repair, not a paint job.
• Think about what is under the paint. Older paint layers can contain lead. Cambridge City Council's advice on lead paint warns against using dry sandpaper, and suggests moistening the surface and using waterproof abrasive paper so no dust is created. If a textured coating such as Artex is involved, the HSE notes that asbestos can be found in buildings built or refurbished before 2000, so have it tested before you sand or scrape.

Filling cracks

The most common faults are a crack along the top or bottom edge where coving meets ceiling or wall, open joints between lengths, and chipped mitres at the corners. Rake out any loose material, dampen absorbent plaster lightly if the filler maker recommends it, and press in a suitable filler. A flexible decorator's caulk is often used for fine cracks along the edges, where there is a little seasonal movement, while a plaster based filler suits chips and joints that need to be sanded and shaped. Let fillers dry fully and sand them flush before painting.

Cracks that keep coming back, or a gap that is widening, usually point to movement in the ceiling or wall behind. That needs looking at before any decorating.

Which paint to use

Always start with the guidance from the coving maker and the paint maker, because the right system depends on the material. A few points we can confirm.

• New gypsum coving. British Gypsum's guidance for its Gyproc cove and cornice is that the surface is treated with its drywall primer before the decorative paint finish.
• New bare plaster. Fresh plaster must be fully dry. Many decorators then use a thinned first coat of a non vinyl matt emulsion, often called a mist coat, so the paint can soak in and bond.
• Old cornice finished in soft distemper. Distemper was a traditional finish for ceilings and fine plasterwork. The paint maker Rabart says its soft distemper will not accept later layers of modern paint, so if your cornice has a powdery, chalky finish, test it before painting over it. Emulsion on top of distemper can flake.
• The finish. A matt finish usually suits coving and ceilings best, because it hides small imperfections and does not flash in raking light.

Cutting in and painting the run

• Paint the coving before the walls. If you are decorating the whole room, the usual order is ceiling, then coving, then walls, so any drips fall on surfaces you have not painted yet.
• Use a good brush. A quality angled sash brush makes it much easier to hold a straight line where coving meets wall.
• Load lightly. Dip only the first third of the bristles and tap off the excess. Less paint gives a cleaner edge and fewer drips.
• Work in sections. Paint an arm's length at a time, keep a wet edge and lay off along the length of the coving, not across it.
• Two thin coats. Two thin coats look better and keep the profile sharper than one heavy one.

Painting ornate cornice without clogging the detail

Conservation writers on buildingconservation.com point out that excessive paint build up obliterates fine decorative detail, turning fine ornament into dull shapes. Each new coat you add makes that a little worse, so ornate cornice deserves a gentler approach.

• Thin the paint slightly if the maker allows it, and use a softer, smaller brush for the enrichments.
• Stipple paint into recesses with the tip of the brush, then pick up any pooling straight away.
• Work along the run so wet paint never settles in the deep parts.
• Keep one coat if the colour covers well. Do not add a coat out of habit.

Painting detail in a different colour is a good way to bring a cornice back to life. The Victorian Society notes that painting is reversible, which makes it a low risk way to try colour on period plasterwork.

When paint build up needs cleaning back

If the egg and dart has become a row of soft lumps, or the paint is crazed and flaking, more paint will not help. The Victorian Society advises that distemper may need steam to soften it, then careful picking out with wooden tools, and that stripper makers' instructions should be followed. Building conservation guidance stresses that test areas are essential before any method is used across a whole cornice, and warns that some strippers can damage plaster. On historic or delicate work, this is a job for a specialist.

Removing old coving, or repairing it instead

Plain modern coving that is simply stuck on can usually be cut free along both edges with a sharp knife and eased off with a wide scraper, working slowly so you do not pull away the surface of the wall or ceiling. Expect some making good afterwards.

Period cornice is different. It may have been run in place, keyed into the ceiling, or be holding the edge of a lath and plaster ceiling together. RICS guidance on traditional plasterwork says retention and repair should be the first consideration, and warns that the plaster nibs gripping the laths can be damaged by extra loading, renovation work or vibration. Pulling at an old cornice can bring part of the ceiling with it. In most period rooms, repairing a damaged run and matching new lengths to the old profile is safer and looks better than removing it. Our guide to Victorian, Georgian and Edwardian coving explains how repairs are matched.

When to call a professional

• The cornice is loose, sagging or sounds hollow over a large area.
• The ceiling is lath and plaster and shows cracks, bulges or staining.
• Detail is badly clogged and needs cleaning back.
• Lengths are missing and need matching to an existing profile.
• The building is listed, in which case speak to your local authority first.

Questions we get asked

Should coving be the same colour as the ceiling?

Often, yes. Painting coving with the ceiling makes the room feel taller, while painting it with the walls makes it feel cosier. Both work.

Can I paint polystyrene coving?

Usually, but check the coving maker's advice, as some coatings and solvents can attack polystyrene.

How do I fit new coving if I am replacing it?

Our guide on how to fit plaster coving covers fixing, mitres and filling joints.

Where to go next. If your cornice needs repair, cleaning back or new matching lengths, see what we restore and fit on our plaster cornice and coving page, or send photos through our contact page and we will tell you what we think it needs.