The Reason For Blister, Peeling, and Fading Of Exterior Doors Painted a Dark Color
This information is useful to determine how colors will “weather” in south Florida’s tropic climate that is closer to the sun’s Uv with hotter humid weather.
White or light colors reflects the suns heat and dark colors absorb the sun’s heat increasing the temperature of the paint and underlying surface. When thin metal surfaces absorb the heat that “increases the surface temperature that can exceed 180 degrees cooking the metal surface causing expansion and contraction of the thin metal sheeting.
Exterior metal doors in South Florida are a factory primed to protect the galvanized metal. The doors are then top coated (painted) at least one time during the construction process and then each time in subsequent repaints.
Dark colors on exterior metal doors will absorption heat and the UV may cause inter-adhesion failures, blistering, film surface cracking, and failure of underlying paints and other phenomena that is beyond the control of the coating system.
In addition to dark colors on exterior doors it is a common phenomenon that over time with multiple coats of paint, the original factory applied primer coat can lose its adhesion and peel to the bare metal.
The peeling of exterior doors is not predictable. If one or more areas of peeling is existing prior to re-painting the door, the paint will continue to peel. Spot priming the bare areas and repainting will NOT stop the continued problem of peeling.
To remedy the problem of any pre-existing problems on doors, the entire door must be completely stripped down to the bare substrate and then follow these procedures.
1. The doors need to be stripped down to the bare galvanized surface
2. Acid etched to remove surface contaminates.
3. Primed with a UCI'S "ULTRA-PRIME" universal metal primer (U.C.I. #3-2200).
4. Repainted in the proper color with a 100% acrylic gloss enamel (U.C.I. #57-100).
Since the doors in a planned community are all the same age this problem may occur on other doors in the community.
The next time the doors are repainted the association should be aware that the problem (of peeling) and budget for stripping or replacing the doors. With additional coats of paint and the aging of the community the problems with the doors will continue.