Ask the Expert: Repainting Aluminum Exposed to Chlorides and Exterior Exposure

Q: I have a somewhat unusual rebuild project situation. Six months ago, we purchased a 67 x 38 foot pool enclosure from a motel. The unit is made up of an aluminum box frame supporting translucent Kal-Wal fiberglass panels and glass. It is about 18 years old. Our plan is to refinish the aluminum and fiberglass before re-erecting. We are thinking about paint. We realize the translucency of the fiberglass will be lost with paint but we are replacing some of those panels with new transparent polycarbonate. The aluminum needs some resurfacing in some spots. We have your helpful advise about repainting aluminum. My guess at this point is to thouroughly clean and sandpaper, acid etch primer bare spots, and epoxy or polyurathane topcoat for aluminum and an enamel for fiberglass. But, we have chlorine in the inside air and New England air on the outside. My contractor recomends acrylic latex for both with primers. That scares me; can you help?

A: Call Pantheon Chemical and consider purchasing some of their X-it Prekote which is a pretreatment for aluminum and is expected to be more effective than an acid etch. Remember to wash all of the chloride contaminants from the aluminum before you start!!!!!!!

Follow Pantheon's instructions to the letter when you prepare the aluminum. Then follow with an epoxy primer and a polyurethane topcoat.

I have not yet used the X-it Prekote, but I will be using it for the first time on aluminum railings in downtown San Francisco on an experimental basis. Based on Pantheon's literature and some of the phone calls I've had with people who have used it, the product seems to be impressive. I am making absolutely no claims and leave it to you to experiment just as I will be doing.