Options for old radiators include painting them, covering them or replacing them. Here are the pros and cons.
Q: I want to cover my hot-water radiators so they will look more decorative, but I’ve received three different contractor opinions on how to proceed.
The first said a cover reduces the heat output by 30 percent and recommended painting instead of covering. The second recommended the usual metal enclosure and not a wooden one because the wood expands and over time will crack.
The last contractor suggested wooden covers and said the wood will not crack.
I want to make the correct choice, but need the pros and cons for each selection.
A: From the advice you’ve received, I am confident that the radiator-cover industry is cartel-free.
I had radiators in my first two houses. At someone’s suggestion, I painted the radiators with Rust-Oleum, because they are metal and you need to have the coating adhere properly to the surface and stand up to heat.
The surface of the radiator needs to be prepped, just like anything else, and if there is rust and corrosion, a wire brush is quite useful. Just make sure that the radiator isn’t rusted through. Prime with a metal primer. Let it dry thoroughly, then topcoat it, maybe twice.
If there is little room between the radiator and the wall behind, paint as far as is visible and let it be. I was cautioned once by a plumber not to move a radiator because you never know how fragile the pipes are connecting below the surface of the floor or the ceiling above.
That said, it takes a long time for the odor of paint to dissipate, and for 11 years after I painted the radiators, you’d think I had just finished. And it was very easy to compromise the paint job by drying towels and wet gloves on the radiators.
In my first house, I had a contractor make me a wooden radiator cover, which doubled as a bookshelf. It had a metal screen of the type sold at home centers and hardware stores in several colors.
The cover forced the warm air through the metal screen and at the person sitting in front of it, instead of letting it rise to the ceiling, where it doesn’t do much good. In fact, it’s recommended that people with radiators and high ceilings install fans to push the warm air down to where people can benefit.
I don’t remember the wood showing any signs of warping. The warm air from radiators tends to be dry — hence the art of putting pans of water under them to try to introduce moisture to a room in the winter.
I imagine, however, that whatever moisture is in the warm air might collect on the inside of the radiator cover and cause some warping over time.
Still, from what I’ve seen online, there are more manufacturers producing wooden covers than metal ones these days. Metal covers get hot, of course, and one of the reasons for using a cover is to protect tiny fingers from touching the fins of the radiators.
I’ve never seen anything about covers reducing heat output by 30 percent.
There is another option if you have some money or are able to do this over time: Replace the radiators.
Modern radiators are much more attractive, smaller and more efficient than the old clunkers that our ancestors came up with at the end of the 19th and in the early 20th century.
Rich Trethewey, the master plumber on “This Old House,” talks about them at www.this oldhouse.com/toh/asktoh/question/0,,385604,00.html.