for Cold Climate Housing and much more

Last Updated: , Created: Sunday, January 14th, 2001

How do you paint a metal roof.

Marie-Paule from Labelle, Quebec gave me the greatest compliment. She sent in a question in French and said that she watches the program all the time but doesn't understand English. I guess our models and graphics are doing some good.

She was asking me how to paint her metal roof because she was a bit upset that the nice red colour had faded.

First, any bright colour will fade quickly in the sun. That is why most siding and roofing materials are dull lighter colours -- so that they can fade gracefully.

The metal roofing manufacturers will tell you to change the roof rather than repainting it and it is true that a factory finish will almost always last longer than anything applied outdoors. The factory roof panels are often catalytic finishes and many are baked on like auto bodies.But you can in fact paint a roof.

First clean it well with a power washer.

Then sand any rust spots and spot prime with a metal primer. Be ready to paint the next day because metal primer does not protect against rust.

Paint with either 100% acrylic house paint, or elastomeric paint. You want a paint that is very elastic and will stretch comfortably with the expansion and contraction of the metal roof, otherwise it will simply flake off.

If you are spray painting, use a water-based paint. Oil-based paint overspray will stay sticky long enough to colour the side of your house, your car, and your neighbours. Water-based paint overspray will dry to a harmless power before it hits those surfaces.

Don't paint while there is morning dew on the roof, when it might rain, when there is too much wind, when it is so hot that you will cook the paint before it can cure, or when it is so cold that it might freeze. Not such an easy task.

Good luck Marie-Paule and someday Quebec will accept my strange accent and we will finally get my live TV hotline show "Manon et Monsieur X" onto the French-language air waves.

Keywords: Finishes, Rust, Primer, Outdoors, Colour, Expansion, Wind, Acrylic, Paint, Metal, Roof

Article 984