Step by Step: How To Paint Metal Baseboard Heater Covers

Let’s face it, baseboard radiators are ugly. They’re boxy, often institutional beige, and they tend to accumulate scuffs and splotches of rust. But baseboard radiators do serve an important purpose, and those of us who rely on them to heat our homes are more or less stuck with them. Fortunately, there are ways to work around these wall-space-hogging eyesores, and painting your baseboard heater covers to match your home’s walls or trim is a great place to start.

And now that fall is approaching and the heating season is coming up, it’s the perfect time to tackle this project. Former Renovation Diary participant Dan Bailey is back to show us the correct way to clean and refinish your metal baseboard heaters so the paint won’t bubble up or flake off the week after you turn the heat on.

• Drop Cloth
• Clean Metal Primer
• Fine Sand Paper or Sanding Sponge
• Paint
• Paint Brushes
• Sponge and Cleaning Bucket

Before we get started, you’ll need to figure out what kind of heating system you have. Baseboard radiators come in two types, electric and forced hot water, and the radiators used with both systems look very similar. If you’re not sure what kind of heating system you have, go to the source. If your home has an oil or gas-fired boiler, usually located in the basement, you have a forced hot water heating system.

If there are separate circuits for radiators or heaters in your home’s breaker panel or fuse box, you have an electric heating system. If you have an electric system, make sure to turn off power to the radiators at the breaker panel or fuse box before doing anything else.

Next, we’ll need to choose the right paint and primer. Since the radiator covers are metal, you’ll need to use a metal primer. If your radiator covers are speckled with rusty spots, you might be tempted to use rusty metal primer. Don’t do it! Rustoleum Rusty Metal Primer contains fish oil, which soaks into and seals rusted metal.

But on areas of clean or painted metal, the fish oil rises to the surface and will cause your fresh top coat of paint to flake off within days. Instead, use Rustoleum Clean Metal Primer or a similar oil-based primer, which works well on clean, lightly rusted, or painted metal.

Your choice of paint will also depend on what kind of heating system you have. Those of us with forced hot water systems don’t have to worry about using heat-resistant paint since these systems don’t get very hot – water usually leaves the boiler at 180 ºF (80 ºC), but by the time it reaches the radiator, the temperature will have dropped up to 50 ºF (20 ºC), and the radiator covers will never become too hot to touch.

Pretty much any paint will work with this kind of heating system – water and oil-based paints work equally well over oil-based clean metal primers. I went with a Benjamin Moore interior latex paint that matches my trim.

Electric baseboard radiators, on the other hand, can theoretically reach temperatures as high as 150-200 ºF (65-95 ºC), which exceeds the heat resistance of most paint. Rustoleum’s Clean Metal Primer is safe to use here since its heat resistant up to 200 ºF (95 ºC). Rustoleum also makes high-heat spray paints that resist temperatures over 1000 ºF (540 ºC), but they come in limited colors and, considering that wood bursts into flame around 600 ºF (300 ºC), seem like overkill for this application.

Luckily, most paint manufacturers offer a range of paints that resist temperatures of 200 ºF (95 ºC) or higher and can be tinted any color that you want. Benjamin Moore, for instance, recommends their line of “Super Spec” alkyd paints in low luster (P23) or semi-gloss (P24) finishes, which are self-priming, can be used on metal surfaces, and resist heat up to 350 ºF (175 ºC).

Sherwin Williams recommends their All Surface Enamel Oil Base paint, which resists temperatures up to 200 ºF (95 ºC). If you’d rather use a different brand of paint but aren’t sure if it can take the heat, shoot the manufacturer an email and ask for a recommendation.

Choosing a paint color is a matter of personal preference, but if your goal is to disguise the radiators as much as possible, you might consider painting them the same color as whatever is directly behind them. So if your baseboards are nearly as tall or taller than the radiators, paint the radiator covers the same color as the surrounding baseboards. And if you have shorter baseboards (or no baseboards at all), paint the radiators to match the walls.

Finally, if you’re looking for a factory smooth finish, you can use spray paint and primer. I chose to use brush-on paint since I don’t mind subtle brush strokes in the finish – I think it helps the radiators to better mimic the look of the wood baseboard behind them.

1. Disassembling the cover will allow you to paint it horizontally on saw horses, which will not only make for a more comfortable painting experience but will also help to prevent drips, leaving a smoother finish. Begin by removing any metal corner pieces or caps from the ends of the radiator. Usually, these pieces slide right off or, if they’re really stuck or painted in place, can be popped off with a flat head screwdriver, but sometimes they’re held in place with one or two screws.

As you remove each piece of the radiator cover, label the back of it with a pencil. Use a labeling system that makes sense to you; I labeled each piece of my radiator covers with numbers, starting on the left with one.

2. Next, remove the front panel, which is usually held in place by two brackets, one at the top and one at the bottom. Lift up and out to pull the panel away from the brackets.

3. Finally, remove the hinged damper that runs along the top of the radiator. The damper is usually clipped into the same brackets that held the front panel in place. To remove it, grab the damper on either side of a bracket and pull it up to pop it out of the bracket. Repeat this process at each bracket along the length of the radiator until the damper is free.

The back panel of the radiator cover is attached to the wall, and removing it is more trouble than it’s worth – we’ll paint it in place. With the front panel and damper out of the way, you should be able to see the heating element. It’s made up of a series of vertical aluminum fins that surround a central pipe, which serves as the heat source.

Tip: If you’re anything like me, you may have never bothered to take apart your radiator to clean under the metal covers, and you may be shocked by the quantity and size of the dust bunnies that have taken up residence around the heating element. This would be a good opportunity to break out the vacuum and clean around the aluminum fins using a brush attachment. If any of the aluminum fins are bent or mashed, gently straighten them – the fins work most efficiently when they’re evenly spaced and separated from their neighbors.

4. Clean the pieces thoroughly (including the part that’s still attached to the wall). Start by scrubbing each piece of the radiator cover with a wire brush, taking extra care to remove caked-on dirt and smooth out any rusty patches. If you suspect that your radiator covers have been painted with lead paint, take all necessary precautions before using any of the following abrasive cleaning methods – or better yet, consider completely replacing your radiator covers. Use a damp rag to wipe away any dust that’s left behind.

5. Next, lightly sand the outward-facing sides of the radiator and cover them with fine-grit sandpaper or a sanding sponge.

6. Now, use a sponge and a bucket of water with a bit of dish detergent in it to scrub down all of the radiator cover parts. After everything has dried, use the sponge and a bucket of fresh water to wipe away any soap residue.

7. Once the radiator covers are clean and dry, prime the outward-facing sides of each piece with clean metal primer. Since this is an oil-based primer, I like to use a disposable foam brush for easy clean-up. Again, don’t forget to prime the top portion of the radiator cover that’s attached to the wall. The primer should be dry to the touch within an hour or so but leave it overnight to fully cure before painting over it with a top coat.

8. The next day, you’re finally ready to start painting. To minimize the appearance of brush strokes, use a good, natural bristle paint brush, and work your way from one end of each radiator cover piece to the other, applying the paint and then spreading it with long, overlapping brush strokes.

Apply two light coats of paint to each piece of the radiator cover, waiting for the recommended drying time between coats. Fresh paint scratches easily, so wait a few days for your freshly painted radiator covers to fully cure before reassembling the radiators.

And just a refresher, here’s the before pic:

And here’s the after:

9. Finally, to reassemble the radiators, just follow the process of taking them apart in reverse. Slide the adjustable clips on the back of the damper to align them with the brackets above the heating element, and then snap them into the top of the brackets. Clip the front plate onto the top and bottom brackets, replace all of the corner and end pieces, and you’re done! Now, with radiator covers that blend in with the walls or trim, it’ll be easier than ever to completely ignore them.

Above, the radiator before (on left) and after (on the right).

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