Repair a Leaking Metal Roof in 4 Easy, Cost-Effective Steps.

Metal roofs are built to last – often coated with factory-applied Plastisol that can protect for over a decade. But after 10–15 years, exposure to the elements can cause the coating to fade, chalk, and lift away, especially around cut edges and seams where moisture creeps in. Left untreated, this can lead to corrosion and costly water ingress that disrupts workshop operations.

Fortunately, Elastometal, a next-generation roof repair system, can restore your roof to a fully waterproof, durable state — without the expense and downtime of a full roof replacement. Here’s how.

Step 1: Diagnose the Problem with a Professional Roof Inspection

Begin with a complete inspection to understand the extent of damage and identify weak points — particularly cut edges, overlapping seams, and roof penetrations like vents or stacks. These are prime locations for corrosion to start.

At this stage, ensure all Health and Safety protocols are in place to protect workers during maintenance. Areas showing exposed metal or edge corrosion should be marked for targeted repair using Roof Fleece reinforcement during later steps.

Step 2: Surface Preparation — Without Abrasive Blasting

Good preparation is the foundation of a lasting repair. Start by clearing gutters and drains of debris to restore proper water flow. Next, clean the panels using high-pressure water jetting (2600 psi) to remove flaking coatings, grease, and other contaminants.

For a deeper clean, add up to 5% Eco Powerclean to your water. This biodegradable alkaline cleaner includes rust inhibitors that help prevent flash rusting while improving surface adhesion for coatings. Let the cleaner react for 2–3 minutes, then rinse and allow the surface to dry completely before coating.

Step 3: Treat Cut Edges and Overlapping Joints

Focus next on areas most vulnerable to leaks. Apply a base coat of Elastometal by brush, embed a 20 cm strip of Roof Fleece into it, then seal with an additional coat to create a flexible, high-build waterproof layer.

Any exposed cut edges should receive one to two extra coats of Elastometal to seal and protect bare metal surfaces from further corrosion.

Step 4: Apply Elastometal — Anticorrosion and Waterproofing System

With the surface cleaned and joints sealed, it’s time to finish the job. Elastometal comes in a variety of RAL colours with a 15% matt finish, ready for use out of the tin. Stir thoroughly before application — and if needed, add up to 3% clean water in hot conditions to slow drying and improve flow.

For best results, apply two full coats by airless spray (to a dry film thickness of 350 microns) using around 0.8 kg/m² of product in total. Roller or brush applications may require an additional coat to achieve the same protection level. Allow 4 hours between coats before walking on treated surfaces, using smooth-soled shoes to prevent damage.

When complete, your roof will have a durable, watertight finish capable of withstanding the expansion and contraction of metal panels for over 15 years — even in aggressive C4 and C5-M coastal or industrial environments, as defined by ISO 12944.

Why Choose Elastometal?

Elastometal is a high-performance, water-based elastomeric acrylic system offering 200% elasticity for long-term flexibility and durability. It combines anti-corrosive protection with direct-to-metal adhesion, eliminating the need for abrasive blasting or additional primers.

Environmental compliance is built in — Elastometal’s low VOC, EPD-verified, and dry-fall formulation makes it a cost-effective, eco-conscious solution for metal roof refurbishment projects in live or sensitive environments.

What about the Vertical cladding and Walls of my Commercial Building?

Metal Unicoat for Cladding and Facades

For building exteriors and metal cladding, Metal Unicoat offers a reliable, high-build primer-finish system that adheres directly to metal surfaces — even when abrasive preparation isn’t practical.

Designed for galvanised steel, plastisol, PVDF, and powder-coated sheets, Metal Unicoat provides excellent colour retention, gloss stability, and long-term weatherability. With low VOCs, no fire risk, and minimal odour, it’s ideal for application in occupied or operational buildings with minimal disruption.

Quick Product Summaries

Elastometal Summary:
A high-build elastomeric acrylic roof coating with 200% elasticity, designed to flex with metal roofs while providing 15+ years of corrosion and waterproof protection. Environmentally friendly, direct-to-metal application saves time, cost, and complexity during refurbishment.

Metal Unicoat Summary:
A durable, water-based primer-finish for metal cladding and exterior surfaces. Combines strong adhesion, colour stability and low environmental impact — ideal for refurbishing façades where abrasive cleaning isn’t feasible.