Ask the Expert Question-and-Answer Archive

by Ron Joseph

February, 2005

Waterborne v. Solvent Base Paints, Coatings and Primers

Q. I would like advice on painting 100 year old cast iron radiators. I have stripped the old finish w/ a needle scaler and now want to paint them with a nickel or pewter paint. What primer do I use? Do I use oil or latex? I have been given conflicting advice at the same paint store (e.g. latex for flexibility, oil for durability)

A. There is a terrible misconception in the industry and among consumers that waterborne paints are inferior to solvent based paints. With today's technologies you can purchase outstanding high performance waterborne paints and coatings. Admittedly, you might not want to use a household latex that you would use on the exterior walls of your house to paint a radiator, but if you go to your local INDUSTRIAL paint store, such as Sherwin-Williams, you should be able to purchase either a waterborne or a solvent-borne coating that will last for years. If you would like the radiator to last another 100 years then apply an epoxy primer, but you will need a spray gun to do so. If you want to use a paint brush, then an alkyd zinc chromate primer will do a fine job.

Good luck.

Best wishes,

Ron Joseph