IBR Roof Sheeting Application Guide

What is IBR sheeting?

IBR (Inverted Box Rib) sheeting is galvanised sheet metal widely used for roofing and cladding. The galvanising process makes the metal more resistant to rusting, but over time all steel can become susceptible to rust. Correct surface preparation and priming ensures a smooth, lasting finish.

Step 1: Surface Preparation

New, unpainted IBR

1. Remove all dust and dirt from the surface

2. Clean with galvanised iron cleaner or sugar soap solution

3. Rinse thoroughly with clean water

4. Allow to dry completely before priming

Previously painted IBR

1. Remove flaky or peeling paint with a scraper or wire brush — strip only the peeling areas, not all existing paint

2. Remove rust patches with a scraper or wire brush

3. Clean the entire surface with a sugar soap solution to remove dust, grime, and oils — use a broom on large roof surfaces

4. Rinse thoroughly with clean water

5. Allow to dry completely

Step 2: Priming

A primer must be applied before painting any metal surface. Primer prevents rust from bleeding through the topcoat and ensures good adhesion between the metal and the paint film.

Marindec recommends: GI Primer — formulated specifically for galvanised iron and zinc-coated steel surfaces.

• Apply by roller, Roof Renovator brush, or spray
• Allow the primer coat to dry completely before painting — refer to the GI Primer TDS for touch-dry and recoat times

Step 3: Painting

Recommended coating: water-based or solvent-based acrylic, or a specialist roof paint.

Apply the topcoat using a roller, brush, or spray. Follow the product TDS for the number of coats and drying time between coats.

Application tips

• Do not paint in direct sunlight or high wind — rapid drying causes an uneven film and poor adhesion
• Maintain a wet edge — work in sections and keep a wet edge to avoid lap marks on large surfaces
• Work ridge to gutter — paint from the ridge downward toward the gutters for consistent coverage
• Allow full dry time between coats — applying a second coat over a wet first coat traps solvent and causes blistering

*For product-specific dry times, recoat windows, and dilution rates, refer to the Technical Data Sheet (TDS) for each Marindec product.*