How to paint a metal gate so the rust stays away

A steel gate is the first thing visitors see and the first thing to show neglect. Orange streaks running down from the hinges, bubbles at the bottom rail, paint flaking off the welds. In most of Kenya a gate faces sun, rain and dust; at the Coast it also faces salt air, which eats unprotected steel fast.

The good news: a properly painted gate stays protected for years. The secret is not the topcoat. It is getting the rust off and building a proper paint system underneath. The same method works for window grilles, burglar-proofing, railings, steel doors and carports.

What you will need

• Wire brush, scraper and sandpaper (or a wire cup on an angle grinder for big gates)
• Maroo Rust Remover for stubborn rust
• A metal primer: Red Oxide Primer, Quick Dry Red Oxide Primer or Grey Metal Primer; Etch Primer for galvanised gates
• An undercoat: Super Undercoat or Universal Undercoat
• A gloss enamel topcoat: Super Gloss Enamel, Master Gloss Enamel or High Gloss Enamel
• White spirit for thinning and cleaning brushes
• Brushes (a 2 inch and a 1 inch for the bars), rags, gloves, eye protection, dust sheet

Step 1: check what your gate is made of

Mild steel (most gates). Rusts when the paint fails. Follow every step below.

Galvanised steel. Has a zinc coating, usually dull grey and slightly speckled. Ordinary primers do not grip galvanising well. Use our two-pack Etch Primer, which is made for maximum adhesion on galvanised and aluminium surfaces, then continue with undercoat and enamel.

Wrought iron or cast iron. Treat like mild steel, with extra attention in the decorative curls where rust hides.

Step 2: get the rust off

This is the step people rush, and it is why gates rust again within months.

1. Scrape off all loose and flaking paint.
2. Wire-brush every rusty area until no loose rust or scale is left. Pay special attention to welds, hinges, the bottom rail, the lock area and anywhere water sits.
3. For rust you cannot fully remove, apply Maroo Rust Remover. It chemically strips oxidation and converts remaining rust into a stable layer ready for coating. Follow the label for application, waiting time and any rinsing. [Placeholder to confirm: rinse requirement and how soon to prime after Rust Remover.]
4. Lightly sand the sound old paint so the new coats grip.
5. Wipe everything down to remove dust and grease. A rag dampened with white spirit removes grease from steel. Let it dry.

Tip: if the bottom rail is rusted through, no paint will save it. Get a welder to cut out and replace the rotten section first.

Step 3: prime bare metal straight away

Bare steel starts rusting again within hours in humid weather, so prime the same day you clean it.

• Red Oxide Primer is the classic choice for steelwork, machinery and metal windows. It comes in 20 litres down to 250 ml, so a small tin is enough for touch-ups.
• Quick Dry Red Oxide Primer is handy when you want to move on to the next coat sooner.
• Grey Metal Primer does the same job and is a better base under light topcolours, such as white or cream gates, because it is easier to cover than red.

Brush the primer well into welds, joints and corners. Two coats of primer on the worst areas is worth the effort.

Step 4: undercoat

An undercoat gives the gloss something smooth and uniform to sit on, and adds film thickness, which is what really keeps water away from the steel.

Super Undercoat is our preferred undercoat for High Gloss, Master Gloss and Super Gloss finishes. Universal Undercoat is a good value base for gloss enamels. Choose an undercoat colour close to your topcoat.

Step 5: two coats of gloss enamel

Gloss enamel is the right topcoat for steel gates: it is hard, it sheds water and dust and it is easy to wipe clean.

| Enamel | Range | Coverage (per litre, per coat, smooth surface) | Packs | |---|---|---|---| | Super Gloss Enamel | Colourtrend premium | approx. 15 to 16 m² | 20 L, 4 L, 1 L | | Master Gloss Enamel | Colourtrend trade | approx. 14 to 15 m² | 20 L, 4 L, 1 L | | High Gloss Enamel | Economy | approx. 13 to 14 m² | 20 L down to 250 ml |

All three are solvent-based and thinned with white spirit if needed. For Super Gloss Enamel the data sheet gives surface dry in 3 to 5 hours, hard dry in 6 to 8 hours, and recoating after 24 hours. Drying always depends on temperature, humidity and how thick the coat is.

How to apply:

• Work top to bottom, one section at a time, so you can keep a wet edge.
• Paint the bars and edges first, then the flat panels.
• Lay the paint on, then finish with light strokes in one direction.
• Watch for runs on vertical bars and below welds, and brush them out before they set.
• Apply the second coat after the recoat time, not before.

Step 6: let it cure before heavy use

The paint is dry to touch long before it is hard. Avoid closing the gate onto fresh paint, banging the latch or chaining it while the paint is soft. Prop it open if you can.

Gates at the Coast and near the lake

Salt air in Mombasa, Kilifi, Kwale and Lamu, and humid conditions around Lake Victoria, are much harder on steel. For gates and steelwork right on the coast, consider a heavier-duty system.

Our Chlorinated Rubber Based Paint is a chlorinated rubber, alkyd-modified coating designed for mildly to severely corrosive environments, including industrial and coastal areas, on steel structures. Pair it with our anticorrosive CR primer, which is made to protect steel exposed to saltwater. See our marine and coastal coatings page, and ask our team to specify the full system for your site.

Keep it looking good

• Wash the gate down every few months to remove dust and salt.
• Inspect the bottom rail, hinges and lock area after every rainy season.
• Touch up chips and scratches straight away: sand, prime, undercoat and enamel. Small 250 ml and 500 ml tins of primer and enamel are made for this.

Frequently asked questions

What is the best paint for a metal gate in Kenya? A full system: rust removal, a metal primer such as Red Oxide, an undercoat, and two coats of gloss enamel such as Colourtrend Super Gloss Enamel.

Can I paint straight over rust? Not over loose rust. Remove loose rust with a wire brush, treat what remains with a rust remover, then prime the same day.

How do I paint a galvanised gate? Clean it, then use a primer made for galvanised steel, such as our two-pack Etch Primer, before undercoat and enamel.

Which colour lasts best on a gate? Every colour lasts longer with good preparation. Black, dark green and maroon are popular because they hide dust and minor marks. Browse the colour catalogue for options.

Get everything for the job from a stockist near you, or call +254 734 411 544 for advice.