Have you tested for lead paint?

No. I suspect it was painted in 2011 by the developer and they didn’t use heat-resistant paint. How would I test?

Buy a $10 lead paint test kit at the hardware store.

You can test for lead if that makes you feel good. If you can catching all the paint scrapings and safely dispose of them without letting anyone eating them, then you will be fine.

Every coat of paint lowers the radiators thermal efficiency. In the old days, they would have simply been given a coat of aluminum paint Were it mine, i would get a spray can of flat black paint and blank out the visible front areas, and then put a radiator cover over it. Black paint will keep the eye from seeing through the louvers or grill on the cover.

Professionally built covers often added a water pan that sits on the radiator and can be used to add moisture to the dry winter air.

It is not hard to put together a simply radiator cover made of wood and metal grill material or use standard shutters to allow air passage.

You can order a custom radiator cover on line for about $200. You can then paint it to match the wall so it is not noticeable, or match the wood work. The grill openings are small so I doubt you will be able to see the peeling radiator. Personally I think that would look better to a potential buyer.

I know how much a Brooklyn brownstone sells for these days. Whatever you do make it look nice and start fielding the offers for your apartment.

Good luck.

Thanks, Houzzians, for all the helpful suggestions!

Last night I was thinking of doing the paint job myself. But after mike_home's comment today I found some shops that make custom radiator covers. This one is in Brooklyn and looks like a good option (no affiliation): https://www.fichman.com/radiator_covers.html

I ordered a custom cover from Fichman. They have a "wizard" where you can enter all the specs and pay on the spot! The only twist is that the steam pipe entry is in the corner, so they will probably need to leave off the right side panel. That will be no problem because it faces the wall.

Here's the valve. Do you think they should just leave off the right side panel?

However they construct it I would want the valve covered. Are they going to leave the back open? The radiator is right up against the baseboard. There is no room for the cover at the bottom. There is a gap between the valve and the baseboard, but It is hard to tell if the cover will fit over it. Maybe they can make a cut out. It won't be visible from the front.

I think the back will be open. I’ve asked them if they can do a cutaway or leave the right side panel off.

if it was mine, I'd sand off the flaky pieces, get a high heat white paint, and touch up the exposed areas. then i'd get or make some type of cover for it...maybe install a wood shelf above it

Nice. Especially the natural wood. I ordered one from the best place I found for custom covers, in a color called Cloud White. I’m going to avoid painting if I can.

That looks like a radiator for a steam rather than a hot water system. That radiator must get quite hot. I'm not sure how suitable a wooden cover at the top would be or how much a cover as illustrated would restrict the function.

In Europe, where radiators are (in my experience) always hot water and not steam, the "mantle" of radiator covers is always some kind of stone, like granite or marble, to help radiate heat from the top. And covers always have more holes, especially on the sides and larger at the bottom, than some of those photos show.

The company makes the covers out of MDF (medium-density fibreboard). Their website says: "Our specially formulated MDF will withstand the dramatic changes in temperature and humidity in your home better than any other material available for radiator covers." It also says "traditional (cast iron/hot steam/hot water) radiators do not get hot enough to start a fire."

Their measuring guidelines put 2+ inches of space between the radiator and the interior of the cover.

Of course there's no fire risk, even steam radiators don't get that hot. I was thinking more about how blocking air flow (especially with a solid wood top with no holes) will limit the heat given off by the radiator when covered.

A radiator open at the bottom and to the front is not going to significantly impede convection heat currents. Stone tops would perhaps form a heat sink to moderate the heat cycles, but the main reason is that it is a stable material requiring very little care. The top of a radiator is a catch all for household items such as keys and nick nacks.

Radiators are the best way to heat a room. they don't require that constant flow of air to keep the room at temperature. That said anybody who is used to these types of heating systems know radiators do not have nice perfect paintwork. I would have simply scraped the loose paint and repainted and moved on.

Radiator covers do cut down on the heat radiating into the room especially without a top that opens. In Brooklyn and the other boroughs the most common covers are made out of metal and are still easily found. I would have went with local craftsman and had one made out of metal that would outlast you.

Nice thing about the old metal covers was the water tray that sat right on the radiator and allowed you to humidify the dry winter air.

Sounds like we have a house divided -- some would just paint, some would make a cover (wood, metal or MDF), some would buy a cover, and some would paint and place a cover. Thanks everyone for your ideas.

I ordered a cover but they said it won't come for 5-6 weeks! This is not soon enough for the house showing. If they can't deliver on time I'll cancel the order and the only reasonable option will be to paint.

I finished the job!

First I stripped with a large and small wire brush. Then I did one coat of the Benjamin Moore color Antique Ivory, plus a few touchups this morning. The stripping made a big mess but I got everything cleaned up this morning.

I taped over the valve before painting (it's on the left).

Not perfect, but cost me less than $100 and it looks ok!

Thanks to all who helped me out. You helped me make a decision and figure out how to make it happen.

Here's the before & after.

It looks very good. I hope the paint chosen will adhere to the radiator when used.

Nice work! Big difference in the before and after.