Winterizing Plumbing in DeKalb Rentals and Vacant Homes
Every December, thousands of rental units in DeKalb empty out for winter break at exactly the point in the calendar when the weather turns. That combination produces the largest water losses we see in this city, and nearly all of them were preventable with an afternoon of work in November.
The failure pattern, and why it costs so much
A tenant leaves for three weeks and turns the thermostat down or off to save money. Temperatures drop into the single digits. A supply line in an exterior wall or above a garage freezes and splits. Nobody is there. The pipe stays plugged with ice for days, then the weather moderates, the ice clears, and water runs at full municipal pressure into the building — for days, sometimes weeks, until someone returns or a neighbour notices.
An occupied unit that bursts loses gallons. An empty one loses thousands, plus the ceilings, floors and units below it.
The pre-break checklist
- Set a minimum temperature in writing. 55°F, communicated to tenants before break, ideally with a clause in the lease. Where you control the thermostat, lock it or set it remotely.
- Disconnect and drain every hose bib. Hoses off, sillcocks drained, and any interior shutoff for the sillcock closed and the line drained.
- Walk every unit. Check that heat is actually on and working, that vents are not blocked by furniture, that windows are closed and latched — a window left open in an empty unit is a fast route to a frozen line.
- Open cabinet doors under sinks on exterior walls and leave them open.
- Change the furnace filter before break. A restricted filter can shut down a furnace on the coldest night of the year.
- Test the heat in every vacant unit. A unit that has been empty since August may have a furnace that will not start when you need it in January.
- Confirm every water alarm has a working battery, or fit them — beside water heaters, washers, under sinks and in mechanical rooms. Wi-Fi models that notify a phone are worth the extra cost on a managed property.
- Identify and label the main shutoff for the building and each unit, so whoever responds at 3am is not hunting.
- Arrange for someone to check the building at least weekly over break, and leave them your number and the shutoff location.
For a property that will sit empty for months
If a unit will be unoccupied long-term, a full winterization is safer than relying on heat:
- Shut off the water at the main and open every fixture to drain
- Drain the water heater and shut off its gas or power
- Blow out supply lines with compressed air, or drain them thoroughly at the low points
- Pour non-toxic RV antifreeze into every trap, including floor drains, and into toilet bowls and tanks
- Disconnect and drain washing machine supply lines
- Shut off and drain any irrigation system and the backflow assembly
- Leave heat at a low setting anyway, for the building fabric if not the plumbing
We do this as a service, along with the spring recommissioning, and for multi-unit owners it is usually cheaper per unit to have it done in one visit.
The pre-winter inspection worth paying for
For managed properties near the NIU campus — the Annie Glidden Road, Hillcrest Drive and Greek Row corridors — we run a pre-winter walkthrough in late October and November. It covers heat operation in each unit, exposed and vulnerable pipe runs, sillcock condition, water heater age and condition, shutoff valve function, and a leak check on the whole building via the meter. Anything found in November is a scheduled repair. The same thing found in January is an emergency with water damage attached.
The insurance angle for landlords
Many policies exclude freeze damage in an unoccupied building where reasonable heat was not maintained. That makes your documentation of the 55°F instruction, the pre-break walkthrough, and the working heat in each unit relevant to more than just prevention. Keep the records.
If you get the call anyway
Shut the water off at the building main. Kill power to affected areas if water is near electrical. Call us at (815) 849-0091 — we answer 24 hours and we work on near-campus multi-unit property constantly. Photograph everything before anyone starts cleaning up, and start air movement as soon as it is safe to do so.
Quick answers
55°F is the widely used minimum and it is what most policies and lease clauses reference. Lower than that and you are relying on luck during a DeKalb cold snap. If a unit has known-cold areas, keep it higher.
For a short vacancy of a few weeks, heat plus a walkthrough is usually the practical choice. For a unit empty for a season, full winterization removes the risk entirely and saves the heating cost. The break-even is roughly a couple of months, but the risk profile matters more than the arithmetic.
Yes, and summer turnover is the best window we get. Empty units let us pressure test, check every fixture and valve, and do repairs without working around anyone. Booking a portfolio walkthrough in July is far easier than in December.
More leak guides
The 30-minute meter test that tells you whether water is escaping, and whether it is inside the house or underground.
Where DeKalb pipes freeze, how to prevent it, and the first five minutes when one bursts.
Eight causes of a sudden bill spike, ordered from the cheapest fix to the most serious.
Leak line, answered 24 hours
(815) 849-0091Call nowOne call does it. We work out what is likely wrong on the phone, quote before we come out, and book you in on the same call.