DIY Tips: Painting Hot Dipped Galvanized / Pre-Galvanized Unistrut Channel

Last month’s blog post on painting Perma Green Unistrut prompted questions regarding painting procedures for two of our more popular finish styles, Hot Dip Galvanized (HG) and Pre-Galvanized (PG) Unistrut channel.  Pre-Galvanized and Hot Dip Galvanized Unistrut are ideal for applications requiring corrosion resistance.  Although the factory finish is perfectly acceptable for most applications, there are also situations where painting with a custom color is needed to add a finishing touch. So, how do you paint Unistrut Pre-Galvanized or Hot Dip Galvanized Channel?

For contractors needing a PDF for submittal purposes explaining how to paint Unistrut HG or PG, download our painting guide here.  For folks interested in a brief description of painting steps, keep reading.T he first thing you’ll need to do is select an application method.  The best methods to topcoat PG and HG channel are liquid or a powder coat finishes. Either procedure will create a thermoset finish with excellent adhesion and performance.  For the sake of this post, we’ll assume you don’t have access to powder coating equipment, so the steps below address a DIY project using air-dry paint.N ext, lightly tack sand the channel to prepare the surfaces for painting.  The goal here is the same as when painting Perma Green Channel—scuffing up the surface for better adhesion rather than stripping the material down to raw metal.  Follow this step by cleaning all surfaces with a damp rag and allow the channel to dry.  Once these steps are completed, you can apply an air dry paint of choice. If you are wondering what type of paint will work best on HG and PG channel, the answer depends on the application.  We aren’t experts on coatings and paints, but your selection should probably contain some kind of corrosion inhibitor if the channel will experience prolonged exposure to the elements.  Beyond this consideration, the list of choices, ranked in order of best probable performance, looks something like this:

• Acrylic Urethane
• Polyester
• Alkyd

For best results, spot test the channel as test data is not available to indicate the performance of this type of topcoat and as always, contact Unistrut Service Company if you have additional questions.  Do you have before and after pictures that show a Unistrut Channel paint job performed in the field?  If you do, send us your pictures and we’ll gladly post them to our Tech Talk area.