Chicago's normal first measurable snowfall at O'Hare is November 18. That is the National Weather Service's 1991–2020 average for the first tenth of an inch, not a forecast. The first full inch normally waits until December 7.
Which means November is the strange month. The pre-freeze work is supposed to be done — if it is not, the October checklist is the one to read first, and it is not too late for any of it. What November adds is a different category of problem: the ones that only exist because the heat is on and the snow has started. An empty house over a holiday. A sidewalk that is now your legal responsibility. And the gallon or two of water a day that your household puts into air that no longer gets vented through an open window.
Three things. What each one actually involves depends on what you own, so the systems are spelled out.
1. Decide what the house does while you are gone
Most Chicago burst-pipe stories start the same way: nobody was home.
What should I set the thermostat to when I travel?
The American Red Cross is specific about the floor: when you are away in cold weather, leave the heat on at a setting no lower than 55°F. Not off. Not 45. Fifty-five is the number that keeps the inside of an exterior wall cavity above freezing on a bad night, and the handful of dollars it costs is not a real comparison to the alternative.
The Red Cross also recommends keeping the thermostat at the same temperature day and night, even though that raises the bill. The reason is the one most people have backwards: a house that swings wide at night is a house whose coldest surfaces — the back of a cabinet on a north wall, the pipe in the kitchen chase — spend hours colder than the thermostat reading suggests.
Then do the two-minute version of this, whether you are traveling or not:
Find your main water shut-off valve and make sure it turns. In a single-family home it is usually where the service enters the basement or crawl space. In a condo or a flat, there is a building shut-off and often a unit shut-off, and they are in different places. Find both now, in daylight, with your phone light, before anything is spraying.
Open the cabinet doors under the kitchen and bathroom sinks on exterior walls, so heated room air can reach the plumbing. Move anything a child or a pet should not reach.
On the coldest nights, let a cold tap served by an exposed line drip. Moving water is much harder to freeze than still water.
Does this change depending on my heating system?
Yes, and this is where generic advice does real damage.
Forced-air furnace. A setback while you are away is fine and sensible — down to 55°F, not below. Leave interior doors open and do not close supply registers in rooms you are not using. Closing registers raises static pressure in the duct system, which makes the blower work harder and does not save the money people think it does. If the plumbing runs through a wall in that unused room, you have also just stopped heating the pipe.
Steam or hot-water boiler with radiators. Here is the one that costs people a wall: do not shut the radiator valve in a room you are not using if there is plumbing in that room's exterior wall. In an older Chicago building, the radiator is frequently the only heat that reaches that wall cavity. Turn it off for a week in January and you have created a cold pocket exactly where the supply line runs.
Two more boiler-specific notes. On one-pipe steam, a radiator valve belongs fully open or fully closed — a partly closed valve traps condensate and gives you the banging. And a boiler system is slow; a deep setback on a radiator-heated building takes hours to recover and tends to produce an overshoot rather than a saving.
Heat pump or mini-splits in heat mode. The counterintuitive one. Do not program a deep setback on a heat pump. When the system has to climb back several degrees, it calls in electric resistance backup heat — the expensive strip heating — to do the work the heat pump cannot do fast enough. A Bonneville Power Administration field study of monitored centrally ducted heat-pump homes found that nighttime setbacks increased energy use by roughly six percent, because the units "worked aggressively to recover from the setback and used inefficient ER" heat in the morning.
So if you heat with a heat pump: hold a steady temperature, and if you are going away, drop it a couple of degrees at most rather than down to the mid-50s. The bill arrives two months later and almost nobody connects it to the thermostat schedule.
If you are in a condo or co-op, and especially if you are the one leaving for three weeks: tell someone. Many buildings require an emergency contact and a key for exactly this situation, and a unit that floods with nobody in it is the single most expensive thing that happens in a multi-unit building. If your association does not have a vacancy policy, raising it is a two-sentence email that makes you popular with the board.
If you own a two- or three-flat and rent a unit, your obligation does not pause because you are away. Chicago's Heat Ordinance runs September 15 through June 1 and requires 68°F from 8:30 a.m. to 10:30 p.m. and 66°F overnight in residential units with central heat and no central cooling; where tenants heat their own units, the equipment has to be capable of holding 68°F under expected Chicago winter conditions. Cooking appliances, water heaters, portable space heaters and fireplaces do not count. Violations run $500 to $1,000 per day, per violation. Make sure somebody can respond to a heat complaint while you are gone.
The cost of skipping it: a split supply line inside a finished wall does not announce itself in December. It announces itself in April, the first time the line is pressurized and the wall gets wet — and by then it is a plumber, a drywall crew, paint, and a conversation with your insurer about how long the water was there.
2. Settle the snow plan now, including where the snow goes
Am I legally required to shovel my sidewalk in Chicago?
Yes. Chicago's Municipal Code (4-4-310 and 10-8-180) makes property owners responsible for clearing the public sidewalk next to their property, and the deadlines are specific:
Snow that falls between 7 a.m. and 7 p.m. must be cleared by 10 p.m.
Snow that falls between 7 p.m. and 7 a.m. must be cleared by 10 a.m.
Seven days a week, weekends included.
The cleared path must be at least five feet wide, including the crosswalk ramps. Corner lots clear every side of the building plus the corner ramps — which is why corner properties are the ones that get ticketed.
Do not shovel snow into the right-of-way: no transit stops, parking spaces, bike lanes or Divvy stations.
Fines run $50 to $500, set case by case by an administrative hearings judge.
If I shovel and someone still slips, am I liable?
Illinois has a statute on exactly this. The Snow and Ice Removal Act (745 ILCS 75) protects residential owners, lessors, occupants, their agents and anyone they hire from liability for injuries alleged to result from an icy or snowy sidewalk condition caused by their removal efforts — unless the conduct was willful or wanton.
Read that carefully, because it is the opposite of the folk wisdom. The statute exists to remove the incentive not to shovel. "I won't touch it, so I can't be blamed" is both a code violation and a misreading of the law. This is not legal advice and a specific incident is a question for a lawyer — but the general shape is: clearing it in good faith is the protected choice.
Where should the snow actually go?
This is the part almost nobody plans, and it is where the expensive mistakes live.
Never pile snow over a gas meter, and never bury an exhaust vent. Peoples Gas is direct about it: clear ice and snow from vent pipes, brush snow off the meter by hand, remove icicles that drip onto meters, and "don't bury vents or meters when using a snow blower or shovel." A high-efficiency furnace or tankless water heater vents through a plastic pipe out a sidewall, often a foot or two above grade. Block it and the appliance either locks out and leaves you without heat, or — much worse — cannot exhaust properly. This is the single highest-stakes item on this page and it takes ten seconds of looking before you throw the first shovelful.
Not against the foundation. A snow pile against the wall is a slow-release water delivery system aimed at your basement. Throw it toward the parkway or the middle of the yard.
Not over the dryer vent or the fresh-air intake either. Same logic as the furnace vent, lower stakes.
What should I put down, and what will it do to my concrete?
Use the least you can. Chloride deicers do real, documented damage: the salt-rich solution accumulates in joints and saturates the concrete, freeze-thaw cycling then breaks it apart from inside, and expansive calcium oxychloride forms chemically. The American Concrete Institute describes the visible result as spalling along joint walls, cracks running parallel to the joint, and raveling where flakes an eighth to a quarter inch thick break away.
Two practical rules:
On new concrete, use sand or cat litter instead. If you poured a stoop, a walk, a garage pad or an apron in the last few years, keep chemical deicers off it — municipal guidance commonly treats concrete as "new" for as much as five years, and many deicer labels say so on the bag. Sand gives traction without the chemistry.
Sweep up what is left once the ice is gone, rather than leaving salt sitting in joints to dissolve again in the next thaw.
What if the association handles it?
Then your job in November is to confirm that it does, in writing, before the first storm — and to know what "handles it" covers. Plenty of Chicago associations contract the front walk and not the back stairs, or the walk and not the gangway. The owner who finds the gap in November is reading an email. The owner who finds it after someone falls is reading something else.
And if you own a two- or three-flat and your lease assigns shoveling to a tenant: that is a common arrangement, and the City's guidance notes it. But the ordinance's obligation attaches to the property. A lease clause is a plan, not a transfer of risk — so have a backup for the week your tenant is out of town.
The cost of skipping it: a ticket in the 50–500 range, a blocked vent that shuts your heat off on the coldest night of the year, and a concrete bill that shows up three springs later as flaking you cannot un-flake.
3. Chase the condensation the heating season creates
A household puts a surprising amount of water into the air — showers, cooking, laundry, breathing, houseplants. From April to October it leaves through open windows. From November on, it has nowhere to go but onto the coldest surface in the room.
What humidity should my house be at in winter?
The EPA's guidance is to keep indoor relative humidity below 60%, and ideally between 30% and 50%. A hygrometer costs about as much as lunch and is the only way to know. Put one in the room you suspect — usually a bedroom on an exterior corner, or the bathroom.
Why are my windows wet, and does it matter?
Water on the inside of a window is a reading, not a quirk. The EPA puts it plainly: condensation on windows, walls or pipes signals high humidity, and the fixes are to insulate the cold surface, raise the air temperature, lower the humidity, improve airflow — and dry the condensation promptly in the meantime.
It matters because of where the water goes next. On a single-pane or older double-hung, the water runs to the sill, sits in the joint between sash and frame, and does what standing water does to wood over four months. In a closet on an exterior wall — no airflow, no heat, cold plaster — the same humidity condenses invisibly and you find out in spring.
What actually fixes it?
Make sure the fans vent outside. This is the one worth checking rather than assuming.
Bathroom fan. Run it during the shower and for fifteen or twenty minutes after. Then go look at where it goes. In a lot of older Chicago buildings, a bath fan was added at some point and terminated in the attic or a joist bay rather than through the roof or wall. That does not remove the moisture; it relocates it to the coldest unheated cavity in the building, which is how you get sheathing stains and, in a bad case, mold above the ceiling.
Dryer. It must vent outdoors, full stop — the EPA lists dryers among the moisture-producing appliances to vent outside. While you are back there, pull the duct and clean it. A clogged dryer duct is both a humidity problem and a fire problem.
Kitchen. If your range hood recirculates through a charcoal filter rather than ducting outside — very common in condos — then you are putting every pot of pasta into the room. Crack a window while you cook, or run the bath fan down the hall.
Then match the fix to your heat.
Forced-air furnace. Dry heat, and most forced-air homes have a humidifier on the furnace. If yours does, it has a setting, and the setting is probably too high for November. Dial it back until the windows stay clear. If you are running a standalone humidifier because the air feels dry, a hygrometer will tell you whether you are at 35% or 55%, and 55% in a Chicago winter is how condensation starts.
Steam or hot-water radiators. Steam systems add moisture to the air by design, and vintage buildings often run humid rather than dry. If your windows are wet and you have radiators, do not add a humidifier — you need less moisture and more airflow, not more water. Those small radiator-top water pans are doing nothing useful in a house that is already condensing.
Heat pump or mini-splits. Neither dries the air much nor adds to it. Your humidity is whatever your household produces, so ventilation is the entire lever. Also: run the fan, not just the heat. A mini-split head cycling off for long stretches leaves a room's air still, and still air is where condensation finds the cold corner.
Window air conditioners still in the window. If one is still in, that is a hole in your wall letting heated air out and cold air in — see October's checklist. For condensation purposes, it is also a cold surface two feet from your furniture.
What about the room that is always cold?
Fix that one before you worry about humidity, because a cold room is a condensing room. On a radiator system, a cold room is usually a stuck air vent, which is an inexpensive part and a short service call. On forced air, it is usually a closed or blocked register, or a damper somebody adjusted in 2009 and forgot.
The cost of skipping it: stained and softened window sills, paint failing on exterior-wall closets, and mold in a corner you cannot see until it smells. None of it is dramatic. All of it is expensive to undo and nearly free to prevent.
If you own a vintage Chicago building
Most of the housing stock here predates 1950, and it behaves differently in a Chicago winter. Four things worth a look while you are at it:
Uninsulated pipes in exterior walls. In a great many older buildings the kitchen or bath supply runs through an exterior wall cavity with no insulation at all. That pipe is the one that freezes while you are in Florida. Pipe sleeve is a few dollars a length where you can reach it; where you cannot, that is what the 55°F floor and the open cabinet doors are protecting.
Storm windows and the condensation trade. Interior storms and good weatherstripping cut drafts, which is the point — but they also cut the accidental ventilation that was keeping your humidity down. Tighten the building and watch the hygrometer; the two go together.
Old masonry and salt. Limestone steps, soft common brick and old mortar take chloride deicers badly. Sand on the steps is the easy answer, and it is also the right answer for a 1920s stoop you cannot replace for anything like the price it was built for.
The sidewalk you did not pour. Many Chicago walks are original and already cracked. Salt in those cracks is water with a freeze point and an expansion ratio sitting inside the weakest part of the slab. If you have been meaning to replace a section, do the replacement first and the salt never.
The short version
Set the heat no lower than 55 before you leave, and know where the shut-off is. Have a shovel plan that includes where the snow goes — not on the gas meter, not on the furnace vent, not against the foundation. Buy a hygrometer and believe it.
None of this is interesting. All of it is the difference between a winter you do not think about and a spring spent on the phone with a contractor.
Vesta Preferred Realty has been helping people buy and sell across Chicago's neighborhoods since 2009. If you have a question about your building — what needs doing, what can wait, or what a repair means for what your home is worth — reach out. We would rather answer it now than after.
