Baseboard heaters can be painted along with the rest of a room, or with an accent color to give some character to the border where your walls and floor meet. The challenge is that the heater covers, unlike other paintable surfaces in your room, are made of metal. They are also subjected to great fluctuations in temperature as they operate. To achieve a strong, long-lasting, good-looking paint job, you have to do some special preparation and use the proper paint.
Any rust must be removed with a scraper, wire brush, and sandpaper. Loose or chipped paint should be removed too. Sand smooth the edges were good paint meets gaps where old paint is missing, to hide the transition between the surfaces. All dust and residue must be wiped off as well or it will interfere with the new paint. Factory finish baseboard heaters should be scuffed with a fine (120 or finer) grade sandpaper, wiped clean, and treated with a liquid de-glosser before priming.
The role of a primer is twofold: to protect the metal substrate while providing a good adhesive surface for the topcoat to stick to. This is an all-important step so it is highly recommended that you prime the metal surfaces first. There are a number of different coating products that can be employed as the primer coating, including a selection of newly formulated waterborne acrylics.
The paint industry has always relied on an oil-based product to serve as a metal covering, including primer base coats. However, concerns about toxic fumes motivated industry chemists to deliver a water-based product that could substitute. The result is a range of products that not only inhibit corrosion but work as powerful binding agents for topcoat layers as well. These hydrophobic formulated primers can either match or exceed their solvent-based counterparts, so they have become the wise—and healthy—choice for baseboard heater cover painting.
While primers help with adhesion and corrosion inhibition, the topcoat is all about color presentation, durability, dirt build-up resistance, and a glossy sheen. Just as with the use of a water-based primer, the use of water-based paints has also become quite popular due to their lack of toxic emissions. Furthermore, a high-quality water-based topcoat can last as much as two to four times longer than similar oil-based paint. Also, water-based paints have been formulated for decreased drying time versus oil. This allows for the quick application of a second coat, leading to faster completion of the task.
Direct to Metal (DTM) Paint
New products on the market today offer a direct to metal one-step painting process for baseboard heaters. These products serve as both primer and topcoat in one. When requesting a DTM paint, ask for an acrylic-based selection. There are a lot of good acrylic latex primers and one-step paints on the market. Explain your project to the clerk, and he should be able to steer you to the appropriate product.
Edward Kimble, a professional painter and author of Interior House Painting Blog, contributed to this article.