Interior vs Exterior Iron Balusters

Posted by Joseph G. Swallow on 26th Jun 2015

Many customers like the combination of wood handrail with iron balusters for their exterior deck or patio installations. So the question is always presented: Can I use off the shelf powder coated balusters outside?

Traditionally powder coated iron and metal balusters are made primarily for interior stair installations. The key is the powder coating, just like paints are designed for interior or exterior qualities. The problem with iron balusters is not that the powder coating peals or chips in exterior weather conditions – nor is rust a factor – but rather the powder coating fades. A satin black baluster, exposed to the sun’s UV rays, will, over time, become gray. Color quality is compromised.

Is there a solution? Here are three options to consider:

I’ve recommended that customers apply a UV clear coat of polyurethane on their balusters prior to installation. I’ve seen many builders in the Pacific Northwest use this method and it appears to have been effective. For the do it yourselfer a can of an off the shelf polyurethane aerosol can be used.

Matte Primed or raw iron can be purchased and pre-painted on sight with exterior grade paint or sent to a local paint finish house for exterior color and preparation. A lot of stair part suppliers offer “exterior” balusters, but these are usually not powder coated.

One of the best ideas I’ve heard was a builder in Virginia who purchased 200 copper vein balusters for exterior installation, with the intent of using an auto clear coat paint finish. He said that the product he uses is purchased from an auto detail supply house and offers the “best protection available”.

House of Forgings is the first to step up to the plate with the introduction of “Deckscape”, a line of exterior ready iron balusters. However, the cost to powder coat was hight, the balusters expensive, and by the summer of 2013 House of Forgings discontinued the entire line.