New shower doors can cost hundreds of dollars, but if you want to rejuvenate or update your existing shower door frames, they can be painted for a small fraction of the cost. Cans of aerosol spray paint are available in a wide range of colours and metallic finishes, and most spray paint that's formulated for outdoor or automotive use will be tough and waterproof enough for refinishing shower door frames. Preparing the doors for painting will be the hardest part of the job. But painting them should be a snap, and it's a job you can do in a day.
Scrub the shower doors, frames and surrounding areas thoroughly with detergent. Rinse and allow to dry. Speed up drying by using a hair dryer, especially in areas where water may settle, such as around the seals and in joints.
Use a razor blade or utility knife to remove any loose or lumpy caulking or sealant from around the edges of the frame.
Sand down any rough spots or nicks on the door frame, and remove sanding dust with a dry, lint-free rag.
Mask the entire area using blue painter's tape and masking paper or newspaper. The more precisely you mask around the frames and door components, the straighter your finished lines will be. Press the tape down firmly with your fingertips to prevent spray paint from bleeding under the edge.
Protect the shower stall and floor with old sheets or dust sheets. If you are spraying the inside of the door frame as well, tape lightweight plastic sheeting to the sides of the stall to prevent them from being hit with paint over-spray.
Spray a coat of metal primer on the door frame. Apply one or two thin, even coats until the whole frame is primed.
Apply several coats of spray paint. Most spray paint dries very quickly, and you'll get a better job, without drips or runs, by applying several light coats of paint instead of one or two thick coats. Let it dry for the recommended time on the can--typically an hour or less--before removing the masking tape and paper.
Re-caulk any areas from which you removed caulking using clear silicone caulking or shower door and tub sealant.
If you need to clean a little over-spray from a smooth surface, such as the shower stall or tile, use acetone. If you don't have acetone handy, use nail polish remover--the active ingredient is acetone and it will clean up most types of paint. Read and follow the spray-paint label directions carefully. There are many different formulas, each with different drying times. While most dry and can be recoated quickly within a very short time, some must be either recoated within one hour, or after 24 hours, otherwise they will wrinkle and bubble. Most spray paints you will find at paint and hardware stores don't require a primer, but some automotive spray paints do. Read the label before you leave the store to see if the paint you're buying requires primer for unpainted metal.
Open windows or at least use a fan for ventilation. Spray paints can have very strong fumes.