Ask the Expert Question-and-Answer Archive

by Ron Joseph

August, 2001

Painting Partitions and Ceramics for Bathrooms Q. Do you have any recommendations or ideally specifications for electrostatic paint on existing metal partitions? In particular, is there a paint that has any chemical resistance? Also, what would you recommend for painting ceramic tile?

The existing metal partitions and ceramic tile are in two dozen washrooms in an office building. I am concerned about uric acid spray on the metal partitions to be refinished and durability on the ceramic tile. Please let me know if you need more information.

A. If you are looking for resistance to uric acid do NOT use alkyd enamels as they will fail miserably. Instead, you might be able to use an epoxy primer and epoxy topcoat, or better still, an epoxy primer followed by a polyurethane topcoat. For these coatings you are advised to purchase the chemical resistant products from an industrial paint store and NOT the consumer products that are available from hardware or building supply stores. ITW Ransburg sells electrostatic spray guns that you can use while painting on-site. I haven't studied their products list, but you can go to their website and look for their portable guns.

You do need to remember certain issues:

• The better you prepare the surfaces, the longer the coatings will last. Surface prep is the key to success!
• The primer and topcoat must be formulated to carry an electrostatic charge.
• The metal parts you paint must be grounded.
• You should be able to use the epoxies and polyurethanes on ceramics (without using electrostatics)
• Read all of the HEALTH & SAFETY instructions for the spray gun and coatings BEFORE you commence work!
• Wear a NIOSH approved respirator specifically designed for polyurethanes
• Do NOT apply the polyurethanes while people are in the work area. Preferably do the job over a weekend or at night to prevent others from inhaling the "fumes." After the coatings have cured for a few hours the potential hazard will have passed.
• Provide adequate ventilation while you are doing the painting.