Lacquering joinery, doors and radiators in Geneva: enamel and preparation

Lacquering: what exactly we mean

Lacquering means applying an enamel — a hard, smooth finishing paint — to interior joinery and metal elements rather than to walls. The scope is precise:

• Dry woodwork: doors, frames and architraves, skirtings, handrails and banisters.
• Metal: radiators and exposed pipes.

The aim is a closed, smooth film, satin or gloss, that resists knocks, rubbing and repeated cleaning — exactly where these elements take a daily beating. In Geneva, period doors and skirtings in the older stock are the most common surfaces, and their enamel shows from a distance, especially under raking light that reveals every relief.

This page is a technical guide: the craft of lacquering, and in particular the case of metal and radiators, which few pages detail. The enamel finishes service covers the service side — doors, skirtings, frames and the enamel of damp rooms (kitchen, bathroom), where washability comes first. The two overlap on woodwork, and that is normal: one explains the method, the other frames the job. To place enamel against matt, eggshell and satin, see choosing your finish.

Preparation makes it last: keying back, degreasing, filling

This is the heart of the trade, and the step you no longer see once the job is finished. A lacquer does not hold through the quality of the product alone, but through the grip prepared for it.

Keying back the glossy surface. Geneva’s older buildings are full of woodwork covered in old glossy oil-based paints. These are closed, smooth surfaces: a new lacquer will not bond to them mechanically. Keying back — light sanding that dulls the surface — is therefore essential. Skipping it guarantees a film that peels in the areas that rub.

Degreasing. Doors and skirtings build up grease, hand marks and dust. An enamel will not hold on a greasy surface: you clean first.

Filling and making good. Screw holes, chips, splits in the wood: you fill, sand and even out. On enamel, the slightest hollow reads, because gloss accentuates defects. The higher the gloss, the more flawless the surface must be.

Primer suited to the surface. This is the central technical choice. You do not use the same primer on wood and on metal:

Surface	Key preparation	Primer
Bare or sanded wood	Keying, dusting off	Wood primer (seals, closes the grain)
Old glossy enamel	Dulling sand, degreasing	Bonding primer
Bare metal / rust spots	Brushing, de-rusting	Anti-rust primer
Sound, already-painted radiator	Keying, degreasing	Bonding primer

Without a suitable primer, even a fine lacquer only delays the problem.

Doors, skirtings and frames: smooth enamel

On dry woodwork, the aim is a smooth enamel: a film that stretches and self-levels to leave as few marks as possible. Modern water-based enamels have largely replaced the old oil-based paints. Two concrete advantages:

• Low smell — the work is far more bearable in an occupied home.
• Reduced yellowing — oil-based paint turns yellow over time, especially on whites and in poorly lit rooms; water-based holds its shade far longer.

The finish is chosen by use and lighting: satin is more forgiving on slightly irregular old wood, gloss is sharper but more demanding on the preparation. Between coats, light keying back removes trapped dust and improves grip: this is the step that gives the smooth result, with no grain to the touch.

On Geneva’s doors and skirtings, often repainted several times, the challenge is also to avoid clogging the mouldings: too many coats drown the relief of period frames. Careful work keeps the profile of the joinery crisp.

Radiators and metal: cold, switched off, the right primer

Metal follows its own rules, and the radiator in particular.

Always cold and switched off. You never lacquer a hot radiator: the paint dries too fast, marks, and does not level. You turn it off and let it cool before applying.

Heat-resistant paint. A radiator heats up in service; the finish must take it without yellowing or blistering. An enamel intended for this use is applied.

Treating rust. On bare metal or corrosion spots, an anti-rust primer goes on first — otherwise the rust returns under the paint and lifts it. On a radiator that is already painted and sound, keying back and a bonding primer are enough. Exposed pipes are treated the same way.

Access behind the elements (between a radiator’s panels, behind pipes) calls for method and the right tool; it is a point assessed during the visit.

Protection, coat order and finish

A clean lacquering job is also about protection: floors covered, masking of adjacent walls, hinges, glazing and hardware. Smooth enamel marks the slightest overrun, so masking tape and cleanliness are not a detail.

The order of work is constant:

1. Preparation — keying back, degreasing, filling, sanding, dusting off.
2. Suitable primer — wood primer, bonding primer or anti-rust primer depending on the surface.
3. First coat of enamel — applied smooth, then left to dry.
4. Intermediate keying — light, for a perfectly smooth base.
5. Finishing coat — the satin or gloss enamel that stays visible.

Between coats, the recoat interval depends on the product, the temperature and the ventilation: it is read off the paint’s technical data sheet and generally takes several hours for a water-based enamel. Recoating too soon locks in defects. Renovhome SA uses paints with low VOC emissions, which matters in an occupied home.

Lacquering joinery fits naturally into a full refresh: walls, ceilings and woodwork are coordinated in the same visit. See interior painting. The work is covered by the 2-year legal warranty (Art. 371 CO). To assess the state of your woodwork and the right protocol, the simplest step is an on-site visit: request a free quote.