Q. What is the best kind of paint and treatment for a lead-coated copper steeple on a church so that the next paint job will last longer than four years? Ruth Garlick Dedham, Mass.
A. This kind of paint job should be resolved by a professional coating expert from one of the larger paint manufacturers in your area. Ask for a specification, which you can then use for bidding purposes with the contractors. This method will put some responsibility on the paint company to produce the proper system.
A paint company's specifications would probably call for the removal of all loose paint, chalk, and dirt down to a firm surface. Dulling of glossy surfaces by sanding is a further probability.
The bare metal might then be spot-primed with a top-quality metal primer suitable for use on lead-coated copper. Follow with one or two top coats of the appropriate finish material selected as to the degree of gloss desired, and related to the type of paint previously applied.
Paint manufacturers like to have these kinds of problems tossed to their technical departments, so don't hesitate to give them a call.