Should you paint stainless steel?

Stainless steel needs oxygen to repair its chromium oxide passive film which prevents corrosion, so not painting stainless is best. Not painting gives good exposure to oxygen, ensuring the stainless can repair itself if any salt or contaminants get on it – so long as it is cleaned and maintained and of a suitable grade and finish. This means for fittings and fasteners on the exterior of houses that are near the coast is ideally polished stainless steel grade 316!

Can you paint stainless steel? Well it partly depends on HOW you paint.

Painting and sealing stainless is fine and OK but this would mean a paint ‘system’ should be put in place that includes an etch primer and epoxy paint, to ensure salt and/or other corrosive agents don’t get in. The risk you run with slapping some acrylic paint over the stainless is that:

a) If it is for exterior use the contaminants can get through the paint as it doesn’t get any rain water or washing. The stainless under the paint could rust and leach through.

b) You get away with no rust or tea-staining but the stainless was not etched and the paint eventually can peel off.

Although virtually any type of paint will bond to a properly prepared stainless steel surface, a two part epoxy paint is the preferred coating. Here is a great guide on how to paint stainless steel.

As far as using stainless fasteners in timber construction goes, research shows that stainless steel corrodes less than other metals and is the fastener to use in treated timber.

NB: This information is provided as a guide only and Anzor does not accept liability for the application of this information.  

Ensure you select which grade of stainless steel is appropriate for your application and be sure to follow good stainless steel guidelines. 

For help and advice on stainless steel grade selection, please contact the Nickel Institute or the Australian Stainless Steel Development Association.