Central Boiler, Dry Air

February 11, 2006 3:28 PM

How can I keep my apartment humid with the window open?

We're getting really dry at night. Sinuses, throat, it's awful. So I finally went and bought a humidifier, and when it didn't do much, I bought a hygrometer (the spelling of which kinda freaks me out), and found out that the relative humidity in the room was 25%.

Now, my understanding is that that's incredibly low. I think the comfort zone is more like 40 to 60. And I read that you need to keep your windows closed to keep the humidity at a decent level in the winter, which makes sense now even though it was counterintuitive at the time: since the air outside is cooler, it can retain less water without having it condense, so 50% humidity outside at 40 degrees is a lot drier than 25% humidity inside at 70.

But there's the problem. Our windows are always open. We have a central boiler (I think) and no way to regulate the heat, so with the windows closed it gets warm fast. So, how do I get the best of both worlds? Do I just need a bigger humidifier? A giant heat sink?

And as an aside.. isn't this incredibly inefficient? How many buildings are like this? It seems like a ridiculous waste of resources for me to be pouring the heat out of the building.

posted by condour75 to home & garden (20 comments total)

You could try leaving the windows open, but putting plastic over them? Less insulating than glass, so it should still let the heat out while keeping moisture in.
posted by Loto at 3:31 PM on February 11, 2006

How many buildings are like this?

I'd say probably 50% of them at least... Most cheap apartments I've seen have been of the "decrepit" type. And most people renting are cheap (and somewhat bad with money, down on their luck, or just plain poor). Hence..... yeah, you got it. :-)

I leave my patio door open at night because the heating is ridiculously hot in my boiler heated apartment. Glad I'm on the basement floor, though... the top floor must be melting.

And yes, it's horridly dry, too. :-( I hope someone here comes up with a good solution.
posted by shepd at 3:39 PM on February 11, 2006

Does the central boiler feed radiators?

If so, you can just place buckets of water atop the radiators. My grandparents did it (with some success).
posted by Kwantsar at 4:33 PM on February 11, 2006

Can't you turn down the steam to the radiators via some sort of knob or churchkey, then close the window?
posted by Orb2069 at 5:10 PM on February 11, 2006

Steam radiators do not turn down; they are either on or off. You can insulate them to reduce their heat output which would be more energy efficient than opening your windows. Radiator covers are one way, essentially a large wooden box with a metal screen or grate in front which covers the radiator. It cuts down appreciably on the radiator's ability to exchange heat into the room, especially if you block some of the screen.
posted by caddis at 5:34 PM on February 11, 2006

I've found that putting a big pot of water (or two) on the stove and letting the water boil off (make sure to keep an eye on it and add more water before it all boils off) puts far more humidity into the air than any humidifier.
posted by needs more cowbell at 5:43 PM on February 11, 2006

My radiators (vintage 1926) have a metal sheet behind them to deflect heat away from the walls and into the room. That shield turns into a little cantilevered shelf that is raised about 3 inches above and covers the top of the radiators (it's kind of cute -- I had never seen that before I got this place).

I leave dishes of water on those shelves, and that seems to help keep the place humid enough. (I, too, use the windows to regulate the level of heat in the apartment, so they're open most of the time -- especially this winter.)
posted by trip and a half at 5:43 PM on February 11, 2006

shepd, where do you live? Are you thinking of flophouses? condour75's problem is well-known throughout NYC, even in quite posh buildings.

Yes, it's stupidly inefficient. Problem is, renovating the boiler system throughout the building is shockingly expensive. It's difficult to get a co-op to sign off on that kind of short-term expenditure, and these are owners. Most landlords would never, ever cough up that much cash on the expectation of saving money over the long term -- they can always cover the excess oil costs in rent, so they don't lose anything anyway.

So, humidity -- condour75, I'm assuming you have radiators. A metal flower box filled with water and secured atop each radiator works wonders. Google "metal flower box" to find a source, local or shipped. Make sure that box is five or six inches longer than the radiator, and HAS NO DRAINAGE HOLES. Install brackets at least an inch longer than the base of the box on either side of the radiator. Use a level (even a straight board) to make sure the box base rests directly on the radiator -- the brackets are supplemental. (But important -- don't cheat.) Fill each box with water up to an inch or so of the lip, and top up as needed.
posted by vetiver at 6:07 PM on February 11, 2006

You might also ask your landlord to install a thermostatic radiator valve. There is an expense associated with it, but you can perhaps sell the landlord on it as saving energy because your window isn't open. Of course, the landlord might just turn the heat down instead and freeze some other folks in the building . This one only works for two pipe systems, either steam or hot water, where you have one pipe bringing in the hot fluid and another draining the cool fluid. If you have a one pipe steam radiator where the steam rises and condensate falls through a common pipe you will need one that installs on the vent.
posted by caddis at 6:08 PM on February 11, 2006

Here is one that installs on a one pipe system.
posted by caddis at 6:10 PM on February 11, 2006

Thanks for the links, caddis. I didn't know such a thing existed. I might look into one of those. Can I tell just by looking at my radiators which kind I have?
posted by trip and a half at 6:16 PM on February 11, 2006

Wow. Some great ideas here, thanks everyone! caddis, I will certainly see about the thermostatic valve -- but if that's not an option the It's not a dump by any means -- and yes, I'm in NYC -- I should've made that clear. Also, it's a steam radiator that's enclosed within the building's outer wall, so there's no real way to put stuff on top of it. However, the idea of putting water directly on the heat seems pretty smart.. if done right, the water could act as an insulator, and the action of evaporation would absorb some of the heat energy, right?

Caddis, any ideas on how to safely cover the radiator vents?
posted by condour75 at 6:26 PM on February 11, 2006

Wow. Some great ideas here, thanks everyone! caddis, I will certainly see about the thermostatic valve -- but if that's not an option the It's not a dump by any means -- and yes, I'm in NYC -- I should've made that clear. Also, it's a steam radiator that's enclosed within the building's outer wall, so there's no real way to put stuff on top of it. However, the idea of putting water directly on the heat seems pretty smart.. if done right, the water could act as an insulator, and process of evaporation would absorb some of the heat energy, right?

Caddis, any ideas on how to safely cover the radiator vents?
posted by condour75 at 6:27 PM on February 11, 2006

sorry about the dupe.
posted by condour75 at 6:27 PM on February 11, 2006

An added point: There's a knob but it just spins round and round, and besides, the whole thing is covered by a metal plate, so adjusting the actual output isn't trivial.
posted by condour75 at 6:39 PM on February 11, 2006

trip and a half: Yes, one or two pipes? The two pipe steam kind has an inlet pipe with a shut-off valve and a separate outlet pipe on the opposite side of the radiator with a trap, a two-pip hot water system is similar but lacks the trap. A one pipe system only has a single pipe entering it. That pipe is usually pretty big. There will also be a vent up near the top of the radiator which lets air out when the steam comes up and then seals once the radiator is hot. Here is a little primer.

condour: You will need to more than just cover the top to significantly cut down on the heat output. Here are some commercial covers. If you make your own I guess you want to make sure it is heat resistant. Cloth covers used to be popular, but I am not sure what kind of cloth would be heat resistant enough. As for the knob, is it a valve? If it is, it is only an on/off valve.
posted by caddis at 6:43 PM on February 11, 2006

commercial covers
posted by caddis at 6:47 PM on February 11, 2006

Thanks again, caddis! Looks like I have the one-pipe system: there's one very big pipe coming out of the floor and that's it. There is also a vent/release near the top of the other side, which I've noticed only does it's thing when the radiator first starts up.

Now I'm all about tracking down one of those in your second link. My building management is pathetic, so I'm thinking I'll just pay someone to come in to install it. Does that make sense?
posted by trip and a half at 7:43 PM on February 11, 2006

All great advice.... I also just found this thread on apartment therapy, which addresses the basic issues as well.

Other info: it's a fin-tube style radiator when I open the metal cover, and there's a brass disc on one end. I'm wondering if this is a thermostatic valve? There's no markings on the visible side and I can't turn it.

Based on the advice so far, I think what I'll do is a) ask my super about thermostatic valves or any other info, b) try insulating the radiator, and c) if all else fails, get a bigger humidifier and leave a window cracked.
posted by condour75 at 8:11 PM on February 11, 2006

Sure.
posted by caddis at 8:12 PM on February 11, 2006