Standard JIS G3312 Prepainted GI Steel Sheet 0.12–1.00mm for Roofing and Wall Panels

1．Product Overview

Standard JIS G3312 prepainted GI steel sheet is designed for roofing sheets, wall cladding panels, prefabricated buildings, and construction applications requiring stable surface coating and forming performance.

The product combines hot dipped galvanized steel or galvalume steel substrate with a continuous color coating system to improve appearance consistency, corrosion resistance, and outdoor durability.

2．Technical Solution

The steel sheet uses galvanized or galvalume substrate together with primer and finish coating layers.

Available coating systems include PE, SMP, and PVDF. PE coating is suitable for general roofing and wall applications. SMP coating improves weather resistance for outdoor use. PVDF coating provides stronger UV resistance and longer service life in exposed environments.

The standard coating structure uses 25±5 micron top coating and 7±2 micron back coating to support stable surface performance and processing consistency.

3．Specifications

4．Application

This prepainted GI steel sheet is suitable for roofing sheets, wall cladding panels, containment systems, prefabricated houses, warehouses, workshops, airport buildings, storage facilities, and decorative construction panels.

It is commonly used where the finished product requires color consistency, corrosion protection, and stable roll forming performance.

5．Processing

• The material can be supplied in coil form or processed into cut-to-length sheets.
• It is suitable for roll forming, bending, profiling, roofing sheet production, and wall panel fabrication.
• Protective film can be applied on the top side to reduce surface scratches during transportation and installation.
• Custom cutting and slitting are available according to project requirements.

6．Advantages

• The galvanized or galvalume substrate provides reliable corrosion resistance for building applications.
• The 0.12–1.00mm thickness range supports mainstream roofing and wall panel production.
• The 700–1250mm width range is compatible with common roll-forming equipment.
• PE, SMP, and PVDF coating systems support different outdoor exposure conditions.
• The standard paint coating structure provides stable surface appearance and coating adhesion.
• Commercial quality and LFQ options support forming and profiling applications.

7．How to Choose

Choose PE coating for standard roofing sheets and wall panels.

Choose SMP coating when improved weather resistance is required.

Choose PVDF coating for projects with stronger UV exposure and longer outdoor service requirements.

Choose galvanized substrate for general construction applications.

Choose galvalume substrate for applications requiring improved heat reflectivity and corrosion resistance.

Confirm coating type, color, gloss level, and protective film requirements before production.

8．FAQ

Q1．What is LFQ
LFQ means Lock Forming Quality, suitable for roll forming and profiling applications.

Q2．What is the available thickness range
The available thickness range is 0.12–1.00mm.

Q3．Can customized colors be supplied
Yes. Customized RAL colors are available according to project requirements.

Q4．Can the material be slit into smaller widths
Yes. Slitting and cut-to-length processing are available.

Q5．Is the product suitable for roofing sheet production
Yes. The material is suitable for roofing sheets, wall panels, and prefabricated building systems.