Painting a metal roof – preparation, paint and costs

Yes, but first assess the roof material and existing finish. A roof with worn paint needs different treatment from one with damaged metal. Painting over a problem without investigating its cause says nothing about the roof's function.

The table supports questions to the contractor. It cannot determine from a photo whether the roof can be painted. For tiles rather than metal, see other material considerations in the guide to painting roof tiles.

Work begins by checking the surface and access. Cleaning, removal of loose coating, any rust treatment and painting are then adapted to the chosen system.

1. Assess the metal and old coating. Document damage and identify previous treatment as far as possible.
2. Plan safe access and protection. Decide how work can be carried out and how surroundings will be protected before roof work begins.
3. Clean and prepare the surface. Follow the system's requirements for cleaning and dealing with loose paint and rust.
4. Prime where the system requires it. The need depends on factors including metal, existing paint and exposed areas.
5. Paint and check the work. Follow product requirements for application, film thickness and drying. The specification should state the number of coats.

This is an overview of the work sequence. It does not instruct you to use the same cleaning method, primer or number of coats on every metal roof.

When can a metal roof be painted outdoors?

When the surface and weather meet the chosen paint system's requirements during both painting and drying. Check surface temperature, moisture and forecasts for rain and dew. A calendar date or particular air temperature alone is not enough.

How do you clean a metal roof before painting?

Cleaning should remove anything that reduces paint adhesion without damaging the surface. Choose method, cleaner, rinsing and drying time according to the coating and paint manufacturer's instructions. Pressure-washing is therefore not a general recommendation for every roof.

Can you paint a metal roof yourself or spray-paint it?

DIY work requires both knowledge of the finish and a safe solution for working at height. The choice of brush, roller or sprayer depends on paint, surface and surroundings. A sprayer does not replace preparation and requires control of overspray.

Professional roof work must prevent falls; a particular roof pitch is not a boundary that makes all other work risk-free. The Swedish Work Environment Authority explains how to manage fall risks. Do not obtain a photo or measurement by climbing onto a roof without safe access.

No reliable lifespan in years can be given for every metal roof. Surface condition, previous coating, workmanship and exposure affect when maintenance is next needed. Request an inspection plan and written terms for the specific work.

A repainting interval is not the same as a guarantee or promise of the roof's remaining life. Monitor rust, peeling and other changes after work and have the cause assessed when new damage appears.

NLL lists exterior roof painting labour at 500–750 SEK/m² including VAT, before any applicable ROT deduction. Materials, access and other costs are listed separately. The price per square metre refers to roof area, not the house's floor area.

The example covers labour only and is not a quote. Materials, access and any other costs must be shown separately. ROT requires both the buyer and work to meet the conditions and sufficient deduction allowance to remain. Materials are excluded. Check Skatteverket's current ROT conditions.

What should the quote include?

The quote should state the area, preparation, paint system, application and access arrangements. Labour, materials and other costs should be distinguishable. Any repairs must be described separately, not assumed to be included in a general price per square metre.

Read more about cost items in the roof painting price guide or use the cost calculator for your project for an initial labour-cost calculation.

Choose a documented system compatible with the metal and existing coating. The name “roof paint” is not enough to establish whether a product suits your roof.

As a specific example, Tikkurila states that Panssari Akva can be used on certain previously painted and factory-coated surfaces, while unpainted metal requires appropriate priming. Product limitations must also be checked. This example shows why the surface must be identified; it does not state which brand NLL uses on your roof.

Ask the contractor to identify the existing coating, explain how adhesion is assessed and specify the product instructions followed. Do not choose a paint combination solely by colour or price.