Your New Noisy Roommate: Steam Radiators in Chicago Apartments

UPDATE: It has come to my attention that this article was linked on October 18, 2012 from a certain HVAC newsletter with the instructions to "find as many errors as possible" in the article. This has resulted in a stream of hate mail and comments including some threatening me with injury and death. As such I have disabled all comments other than one from a solitary, polite commenter which explains how radiators are supposed to work in a perfect situation, even if they don't work that way in most budget-range Chicago apartments.

So, it was 41 degrees last night in Chicago. Many of you probably found yourself searching the web for "Chicago heating laws" or something similar. They exist. It gets cold here. Heat is considered a life-essential service for a little less than 3/4 of the year. Today we're featuring a handful of facts that you should know if you're owning or living in an apartment with landlord-provided steam heat.

They will make noises, but they shouldn't be too loud.

Here's the basic premise of a steam radiator. Water is heated in a boiler down in the basement. It turns to steam, which flows up a big pipe, past a few safety valves and into your big clunky radiators. The metal radiators absorb the heat from the steam, which condenses back into water as it cools. The water flows back down to the boiler either through the same pipe or through a separate, slightly narrower pipe. Repeat ad infinitum. These are called one-pipe and two-pipe systems, respectively, and they are very, very common in Chicago's old-school vintage walkup apartment buildings.

That's a lot of physics going on. In a perfect situation you would hear no noise, but these are Chicago apartments we're talking about here. The systems are rarely in good condition, but they'll suffice. What's important here is to know what's reasonable and what's dangerous. You will hear some ticking as the metal radiator expands & contracts in reaction to the temperature changes. There will be some hissing as excess air escapes through the pressure release valve on your radiator. You may even hear the gurgle of water as it flows back out. These are all normal sounds and part of living with your noisy new heat-giving friend. However, there's one sound that you should not hear: knocking.

Knocking is a bit of a misnomer. I've had any number of concerned calls from tenants who heard the normal ticks and pings I mentioned above and thought that there was a problem. That's normal. Knocking, on the other hand, sounds like a .357 Magnum went off in your apartment. It will make you jump. It will make you drop things. It will wake the baby. You will know something is wrong.

If you hear knocking, first check to make sure that your steam entry valve is all the way open or all the way closed. Steam valves in most apartments are not like thermostats or control dials. There is no middle point. Your radiator either has steam in it or it doesn't. By leaving the valve partway open (or partway closed, if you're a pessimist), you'll simply be forcing full steam ahead through a smaller opening. As in other cases where gas is forced through too small of an opening, your radiator will belch - this will sound to you like knocking. If you can't turn your valve at all due to the knob being either missing or stuck, call your landlord to get that repaired. You should be able to adjust it.

If you've checked your valves already and you're still hearing big loud bangs, you'll definitely want to call your landlord. They should resolve the issue by either bleeding excess air from the system, putting a shim under the radiator so that accumulated liquid water can run out, or replacing the entry valve. You should not have to do any of these things yourself. Steam radiators are cast iron and VERY heavy and VERY dangerous for you to detach from a pressurized steam heat system on your own.

Efficient but still using fossil fuels.

Something has to heat all that water. Here in Chicago, it's natural gas. 90% of Chicago homes were heated by the good people of People's Gas, between the buildings with boilers and the ones with gas-fired furnaces.[1]

The cost-effectiveness is about the same between steam heat and gas-forced air heat. The age of the boiler, insulation qualities of the building and its windows, and the behavior of the tenants will have a greater effect on fuel consumption than switching from one method to another.

Water-based heating systems have some built-in issues

Ever noticed that steam radiators tend to be positioned right next to the windows? That's supposedly so that the heat counteracts any drafts from the windows. so that the cold air pushes the heat into the unit via convection current. The actual effect is that most of your heat is lost to the path of least resistance - to outdoors, through your leaky old apartment windows. If the landlord is still using the old sash & storm windows with the rope or chain based counterweights, chances are good that you're going to lose the benefit of the convection currents. Do what you can to seal the windows in the winter using either heat-shrink film or temporary weatherstripping.

Additionally, as I discovered one Thanksgiving weekend while I was still a renter myself, steam heating systems have a single point of failure - the boiler. Lose the boiler and the whole building is in for a cold night.

You may remember from your pirate lore that steam was used to make wood bend into nifty curved boat-like shapes. There is, therefore, a problem with these heavy, cast iron steam radiators hanging out in vintage apartments that tend to have wood floors. If your radiators aren't properly maintained (which is likely), after constant exposure to steam the wood will bend, sag and lose its varnish. A steam system means the landlord may have to replace the floorboards next to each radiator as frequently as every 3-4 years.

Lastly, the radiators themselves have two major points of potential issues. The steam valve (shown in the photo above on the bottom left) and the air release valve (upper right) are getting steam pushed through them all winter long. They can build up hard water deposits, cat fur, dust, or just plain wear out over their lifespan. If either is not working properly, you risk either no heat to that radiator, steam spewing from the steam valve, or dripping from the air escape valve.

Naked Radiators: A Moral Dilemma

Partially-stripped radiator sitting next to its cover.

There's two ways to cover a radiator, and both of them are pretty important. The first involves paint. Many old radiators have accumulated coats of paint over their lives, either to cover up rust or just blend in a bit more with the rest of the decor.

Many landlords don't realize that there's special radiator paint available and will therefore cover radiators in latex paint. Standard water-based latex paint will not work when dealing with a radiator. The heat extremes will melt it. Only smelly, fumey oil-based paints will adhere to them and stay put. If a landlord has used anything else, it will either melt, crack or sag over time and reduce the heat conductivity.

If you're dealing with a radiator that's got too much paint or the wrong kind of paint globbed on, that paint will eventually interfere with the metal's ability to release heat into the room. (Hint - if you can no longer see the detail on the radiator, it's time to scrape it down.) Landlords who are repainting their radiators are advised to very thoroughly scrape each one outdoors down to a smooth finish before repainting, and to use only paints approved for high-heat situations in a well-ventilated area.

Meanwhile, radiator covers, while thought of by some to be a purely cosmetic idea, can be a boost to both safety and heating power. A good cover will redirect heat back into the room. A bad one will amass a cloud of warm air inside and prevent it from escaping. More important, radiator covers prevent nasty burns.

With 70 degree air coming out of a forced air vent, it's pretty tough to burn yourself. Steam radiators, on the other hand, are filled with a substance - steam - that lists "scalding" in the "special skills" section of its resumé. Radiator burns in Chicago housing projects became such an issue in the early 90's that the Center for Disease Control released a report mandating the owners of the 73% of project apartments with missing covers to remedy the problem immediately.[2]Centers for Disease Control, "Home Radiator Burns Among Inner-City Children -- Chicago, September 1991-April 1994", Morbidity and Mortality Weekly Report, Sept 27, 1996.

However, radiator covers are about $140-160 a pop, while replacement radiators on ebay can be had for $100 or less. Even though ethics and energy savings might lead you to a different conclusion, a savvy landlord looking out for their bottom line will probably not spring for the cover unless a voucher inspection makes it mandatory. When they do get a cover it won't be one designed to maximize heat. It will be a decorative one to prevent you from touching the bare metal, and it will probably reduce the effectiveness of the radiator.

General hint: some renters ask landlords to cover their radiators because they're worried about their pets getting burned. Your pet has probably figured out by now that the stove and oven are not places to hang out. They will also learn to stay away from the radiators pretty quickly. General hint #2: it's tempting to put animal containers like fishbowls, hamster cages, and terrariums on top of the radiators. Unless you like vichyssoise, roast hamster and/or very hyperactive reptiles, I recommend that you find another flat surface to use instead.

Too Hot? Get a blanket.

Other things that you can put on radiators: Coffee cups, bowls of water, damp clothing, nicely scented glass-encased candles that you don't mind melting.

Please don't open the windows. These heating systems take a long time to change directions in response to thermostat activity. Even if the system knows it's too hot, it will take hours to cool off. However, if you shock the temp sensors by opening a window to release the heat, they will tell the system to stay on instead. You'll keep sweltering and the energy will be wasted.

Instead, if you're too hot, first start by carefully turning off radiators in your apartment one by one. Remember that the steam valve wants to be either all the way open (turned all the way counter-clockwise) or all the way closed. Top-floor tenants may be able to turn off every single one except for the one in the bathroom and just coast on the heat rising into your apartment from downstairs.

If a valve is jammed or too hot to touch, another option for a lesser step down in temperature is to take a heavy blanket and throw it over the radiator. The blanket will absorb some of the heat. Just don't do this with any blanket you value too dearly, nor with any acrylic or plastic-fleece blanket, as it may melt. (And seriously, if your valve is stuck, go for the blanket instead of a wrench and call your landlord for service. I once saw a tenant get very badly scalded all down her forearm when her valve exploded out of the pipe.)

Too Cold? Get a blanket.

If the landlord is providing heat, Chicago mandates 68 degrees Fahrenheit from 8:30am to 10:30pm and 66 degrees the rest of the time, from September 15 to June 1. For some of you this will be mighty chilly. I've unfortunately seen tenants call in to complain about their apartments being too cold, but if the temps are above these minimums there's no real legal recourse.

If your apartment is above 70 degrees and you're still cold, get a sweater. Your landlord won't budge. Do not get a space heater. Heating devices put an enormous strain on electrical systems, many of which are already pretty ancient in vintage, steam-heated Chicago apartment buildings. If your apartment is below 66 degrees, you can request a neutral third-party inspection from the City of Chicago. (Note: landlords can do this too if they need to end a temp dispute!) If it stays below 66 degrees for a sustained period of time you get other rights within the landlord-tenant ordinance, which I won't get into in-depth here.

Gravity is a factor.

This is a fun one. Steam rises. Heat rises. A radiator on the same level as the boiler will not get any heat at all. Therefore, if you're living in a garden apartment you may see your radiators mounted on the ceiling so that the steam can at least be going slightly upwards in order to reach you. There's one problem though - heat still rises. Your ceiling will be toasty but your toes might get kind of cold.

If you are in a first floor apartment above a garden unit with ceiling-mounted radiators you will reap the benefits with nice warm floors throughout. Consider it a perk and knit some nice sweaters for your poor downstairs neighbor.

Steam radiator = Window AC.

She may be a looker, but all she can do is cook.

If you've got steam heat there's very little chance that you will have central air conditioning in the same apartment. Steam is by default a super-energized version of water; in other words, it's hot. If you manage to cool something off with steam I know some people who would love to give you a ton of grant money.

Very few investors looking to maximize cash flow are going to go to the trouble of installing a second HVAC system just to get you central air. If they're going to do that, they'll just put in a furnace while they're at it, split up the meters and put the heating bills in your name. Unfortunately, if you want the benefit of your landlord paying for your heat, you're going to be stuck with window units during our scant few warm months here in Chicago.

Let me know if I missed anything, and happy steaming!

EDITED October 21, 2012 to reflect new information.


2 Centers for Disease Control, "Home Radiator Burns Among Inner-City Children -- Chicago, September 1991-April 1994", Morbidity and Mortality Weekly Report, Sept 27, 1996.

5 Responses so far.

  1. SJ says:

    The steam radiators are on in my multi-unit condo building for the first time since I moved in (I’m renting from the owners of this particular unit.) I think the one in the living room is fine, if annoying, but the one in the bedroom was on for about 10 minutes when it started continuously hissing very loudly without a break. Much more loudly and more sustained than the living room. We turned it off all the way and it stopped. Was this just normal start-up behavior? Or do I need to call my absentee out-of-state landlord to get someone to repair it?

    • Kay Cleaves says:

      This is not normal behavior. Normally you’ll get a little hiss now and then, like a steam iron occasionally releasing little puffs of steam. It shouldn’t be hissing continuously, though. Sounds like the steam vent is stuck open. I’d say it’s worth a service call.

      • SJ says:

        That’s what I suspected. Thanks for your help! I’ll give them a call. Very helpful info page for people who have never had to live with one of these before.

      • teresa says:

        Hello Kay,
        Good job bringing steam heating to the forefront and trying to debunk many popular misconceptions. Unfortunately much of your information is incorrect. A properly working system should be virtually silent and never gurgle, nor should steam ever be coming from the vents, only air. In my hundred yr old house my floors are perfect because the system is in proper working order. Two-pipe system can be partially closed or have TRV (Thermostatically regulated valves) put on to regulate the heat in individual radiators. Radiators (and heating ducts for that matter) are placed beneath the windows to take advantage of convection resulting from the colder window. This forces the heat INTO the room as opposed to just near the radiator. Residential steam system are designed to operate at LOW pressure ( less than 2 lbs). Anything more can and will result in many of the problems you describe. Radiator paint can have a large effect on heat with the pretty metallics giving off less and dull black giving off the most. Radiator covers will help protect from burns, but almost all will decrease the amount of heat going into the room by a potentially substantial amount A well designed cover will be tallish and open on both bottom and top, but solid in the middle. This is to aid convection by creating a chimney effect, thus pushing the air further into the room. Such a cover can increase the efficiency of the radiator by as much as 30%. Added to a black radiator with a reflective backing on the cover and the savings, efficiency and warmth really increase. The perceived warmth will increase as well as the heat is more evenly dispersed throughout the room.From a heating standpoint, no cover is better than a poorly designed one. If you’d really like to learn about steam heat please visit [site redacted by admin]. There are great, easy to understand articles on all manner of heating systems, but with excellent explanations of many of the points I’ve touched upon concerning steam. Steam is a beautifully efficient system, but only if properly understood. Fortunately, there are a few VERY knowledgeable steam experts working in the Chicago area. You can find them on the site listed under “Find a Professional”. I do appreciate the intention of this post. CTD

        • Kay Cleaves says:

          Thanks for your polite reply with your corrections. Unfortunately your Heating website has sent me a slew of hate mail including threats to my person. I will closing comments after this particular exchange and take steps to block all traffic from the newsletter that instructed your members to come over here, ridicule & insult me. Needless to say I will not be visiting the site and you seem to have a far different opinion of the membership over there than I have gained from this first introduction to them.

          Your steam heating system in your house is well-loved and cared for by a homeowner who pays attention to such things. Many renters and radiators in vintage Chicago apartments are in low-income rentals with systems that are rarely maintained, or worse, they are in condo buildings with associations that don’t have the funds anymore to do regular maintenance. Many of these radiators are noisy, knocking beasts covered in white matte latex paint, on one-pipe systems.