PPGI coil for garage door panels is the prepainted galvanized coil that forms the steel skin of sectional and roller garage doors. This guide explains how to choose the right RAL color, paint system, coating weight and gloss level for residential and commercial garage door production.
Garage door panels are roll-formed and stamped from prepainted galvanized steel coil (PPGI), and the paint system on the coil is what the homeowner sees for the next 15–25 years. Choosing the right combination of RAL color, paint chemistry, gloss level and coating weight is what separates a garage door that retains its showroom finish from one that chalks and fades within a few years. For OEM garage door production, the PPGI specification is one of the most consequential cost-and-quality decisions.
Paint Systems for Garage Door PPGI
For residential garage doors in temperate climates, standard polyester (PE) paint is the typical specification, with 5–10 year color retention. For premium residential and most commercial doors, SMP (silicone-modified polyester) is the upgrade, giving 15–20 year color and gloss retention. For coastal installations or premium architectural doors, PVDF is the high-end choice with 25+ year retention. The interior face of the door (the back of the panel) typically uses standard polyester in a neutral light gray or white, since it sees no UV exposure.
Standard RAL Colors and Custom Color Matching
The most common garage door colors in Europe and Asia follow RAL standards: RAL 9016 (traffic white), RAL 9002 (gray white), RAL 7016 (anthracite gray), RAL 7035 (light gray), RAL 8014 (sepia brown), RAL 8019 (gray brown), and RAL 9005 (jet black) are the top sellers. Most PPGI mills stock these RAL colors in polyester and SMP at short lead time and minimum order quantity of one coil. For custom colors, allow a 5–10 ton minimum and a 3–4 week lead time for color matching and trial production.
Substrate, Coating Weight and Press Forming
Garage door PPGI substrate is typically 0.30–0.50 mm thick galvanized steel, with Z100 (100 g/m²) coating for inland residential, and Z180 for commercial or coastal. The galvanized substrate must be suitable for deep drawing and stamping without flaking the paint, so specify CQ (commercial quality) or DQ (drawing quality) per ASTM A653. For wood-grain print patterns, the PPGI coil is printed then clear-coated; for solid colors, the coil is simply painted. Embossing and stamping of the panel face requires the paint to have enough flexibility to withstand the deformation without cracking.
Protective Film, Slitting and Packaging
Garage door PPGI is supplied with a self-adhesive PE protective film on the outer painted face, to prevent scratching during slitting, roll-forming, stamping and shipping. The film should be UV-stable for at least 6 months of outdoor storage, and should peel cleanly without adhesive residue. Slitting is to the customer's required coil width (typically 100–300 mm for sectional door panels), and packaging should include desiccant and a weather-proof wrap for export container shipments.
What to Specify on the Garage Door PPGI RFQ
State the substrate standard (ASTM A653 or EN 10346), the coating weight (Z100 or Z180), the substrate thickness, the paint system (PE, SMP, or PVDF), the topcoat color (RAL or custom with reference sample), the gloss level (typical 30–40% for residential), the protective film type, and the coil inner diameter and outer diameter limits. For most residential garage door production, PE in a standard RAL color is the right specification; for commercial and premium, default to SMP. Always confirm a color sample against the reference before bulk production.
Related Resources from Baobin Steel
- Steel coil catalog – galvanized and PPGI options
- Mild steel overview – grades and standards
- Request a quote – send your RAL reference for PPGI pricing