{"id":5900,"date":"2026-10-09T14:58:50","date_gmt":"2026-10-09T06:58:50","guid":{"rendered":"https:\/\/www.raxdoors.com\/blog\/roller-shutter-powder-coating-colours\/"},"modified":"2026-10-10T05:30:11","modified_gmt":"2026-10-09T21:30:11","slug":"roller-shutter-powder-coating-colours","status":"publish","type":"post","link":"https:\/\/www.raxdoors.com\/fr\/blog\/roller-shutter-powder-coating-colours\/","title":{"rendered":"Rev\u00eatement en poudre des volets roulants : des couleurs qui durent"},"content":{"rendered":"

The roller shutter on a street-facing warehouse still opens and closes perfectly in its third rainy season. The colour no longer matches the signage above it. The west elevation faded first, the surface now leaves a chalky film on a finger, and the first quote to fix it is for repainting the curtain in wet paint. That quote solves the colour for a year or two, and then the cycle starts again. Paint layers build up and add weight to the curtain, and the new coat wears through even faster than the finish underneath.<\/p>\n

Our factory has galvanized and powder coated shutter curtains since 1999, and the finish is specified, not improvised. This guide covers the application process and the RAL system behind roller shutter powder coating colours. It also covers realistic service life, resin selection, brand colour matching, and the recoating decision when a finish finally fails.<\/p>\n

How Powder Coating Goes Onto a Roller Shutter<\/h2>\n

Roller shutter powder coating colours are decided long before the oven, at three stations: pretreatment, application, and cure. Dry powder is charged electrostatically and sprayed onto the grounded metal, where it clings evenly across profiles a brush or roller could never cover. The coated slats then pass into a curing oven, where the thermoset powder melts, flows, and cross-links into a continuous film. The result behaves more like a glazed ceramic surface than a coat of paint, because nothing in it was brushed on wet.<\/p>\n

Pretreatment decides whether any of that survives. Oils, rust, and mill scale block adhesion, and one industrial powder coater notes that even small amounts of contamination cause premature failures. On our line the sequence runs on a hot-dip galvanized substrate, so the steel already carries a sacrificial zinc layer under the powder. The two layers do different jobs: the zinc corrodes first if the film is breached, and the powder takes the UV, impact, and cleaning.<\/p>\n

    \n
  1. Clean and treat.<\/strong> Degreasing and conversion treatment give the film its anchor; this stage is where most early failures are actually created.<\/li>\n
  2. Form or take formed slats.<\/strong> A galvanized coil is roll-formed into the curtain profile, the path DASMA describes for powder coated curtains in its field data.<\/li>\n
  3. Apply the powder.<\/strong> An electrostatic gun charges the powder so it wraps the slat faces, including edges where liquid paint runs thin.<\/li>\n
  4. Cure on schedule.<\/strong> Oven time and temperature are controlled to the powder’s specification; an under-cured film chips, an over-cured one discolours.<\/li>\n
  5. Inspect before dispatch.<\/strong> Film thickness and adhesion checks catch the batches that would fail in year two instead of year fifteen.<\/li>\n<\/ol>\n
    \n\"Worker
    Electrostatic application: charged powder wraps the profile, including the edges where paint runs thin.<\/figcaption><\/figure>\n

    The process explains the price difference buyers meet at quotation stage. Powder is a factory operation with ovens and pretreatment tanks behind it, which is why it cannot be matched by a brush applied to a fitted door. It also explains batch consistency: slats coated in the same run share one film, which matters the moment a colour has to match across a whole curtain.<\/p>\n

    There is a weight argument too. Wet repaint cycles build film on film, and DASMA’s wear sheet treats that accumulation as a given of field painting rather than a defect. A factory powder film arrives at its designed thickness in one pass, so the curtain carries exactly the mass it was engineered for. On a wide door running twenty cycles a day, weight is not cosmetic tidiness. The springs and the operator were sized against the design mass of the curtain.<\/p>\n

    Powder Coating Against Wet Paint and Plastisol<\/h2>\n

    Buyers comparing roller shutter powder coating colours against the alternatives are really choosing between three chemistries. Wet paint is applied liquid and dries by evaporation; plastisol is a PVC plastigel heat-cured into a flexible textured skin; powder is a dry thermoset fused onto the metal. Powder also contains no solvents, so the factory line releases no volatile organic compounds in the first place. One UK shutter maker, whose builder lists both factory finishes, puts powder against plastisol directly and prices the trade-off honestly. Their figures: powder at GBP 28 per square metre against plastisol at GBP 15, with the full RAL range reserved for powder.<\/p>\n\n\n\n\n\n\n\n\n\n
    Property<\/th>\nPowder coating<\/th>\nPlastisol<\/th>\nWet paint (field applied)<\/th>\n<\/tr>\n<\/thead>\n
    Colour range<\/td>\nFull RAL range<\/td>\nFixed palette only<\/td>\nAny colour, but site-mixed<\/td>\n<\/tr>\n
    Surface<\/td>\nSmooth, uniform film<\/td>\nLightly textured<\/td>\nDepends on site application<\/td>\n<\/tr>\n
    Impact and wear<\/td>\nHighest of the three<\/td>\nGood, softer skin<\/td>\nWears soonest on a coiling curtain<\/td>\n<\/tr>\n
    Application control<\/td>\nFactory booth and oven<\/td>\nFactory cured<\/td>\nUncontrolled site environment<\/td>\n<\/tr>\n
    Best for<\/td>\nCustomer-facing and exposed elevations<\/td>\nBudget jobs in standard colours<\/td>\nTouch-ups, not first specification<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

    DASMA’s data sheet on rolling steel door paint wear<\/a> adds the field evidence: field-painted curtains show wear marks sooner because they are applied after installation in an uncontrolled environment. The same sheet notes that repaint cycles add film thickness without adding life, which is the trap in the opening quote of this article. Where a door faces the street, the roller shutter doors<\/a> specified in powder hold both colour and film through far more cycles.<\/p>\n

    \n\"Worker
    Wet spray has its place on structural steel; a coiling curtain asks more of its film than a static beam.<\/figcaption><\/figure>\n

    None of this makes plastisol wrong. For a back-lot door in a standard colour, the cheaper skin does the same job for years. The specification question is whether the colour itself carries value, and that question is answered before price is compared.<\/p>\n

    A practical way to draw the line is to look at what the elevation does for the building. A door seen by customers, residents, or a planning officer carries appearance value every day of its life. Powder is the only finish that pairs a full colour range with a hard factory film. A door behind a fence, between loading bays, or screened by an awning is carrying none, and plastisol in a stock shade is the rational buy. Walking the site before quoting settles most of these debates in five minutes.<\/p>\n

    RAL Matching: Getting the Colour You Specified<\/h2>\n

    RAL is the backbone of roller shutter powder coating colours. Because powder manufacturers tint against the RAL system, a shutter can be ordered in any RAL reference rather than a maker’s fixed palette. Powder suppliers keep a stock list of common references and mix the rest to order. Stocked colours therefore ship faster, while special references carry a surcharge or a longer lead time. Ask any supplier which side of that line your colour falls on before promising a date.<\/p>\n

    The working sequence is simple and worth insisting on. The RAL number goes on the order, not a colour name or a photograph. A sprayed sample is approved before the production run, because a colour on a screen and a colour on a curved steel slat under daylight are different things. Then the batch runs, and every slat in the curtain carries film from that batch.<\/p>\n