Winterizing a fourplex costs less than one burst pipe, but the sequence matters
A fourplex with four separate heating zones is actually easier to prepare for cold weather than a building on one boiler, because each unit failure stays contained. The risk that gets missed most often is the shared plumbing chases between units where insulation is thin or missing entirely. A pipe that runs through an unheated garage or crawl space under unit one can freeze and flood unit two's ceiling, and the tenant in unit one never knew anything was wrong. That chase is worth finding in October, before a plumber's emergency rate kicks in. Standard winterization on a four-unit runs somewhere between 800 and 2,400 dollars depending on how many systems share a single point of failure, how old the boiler or furnaces are, and whether the building has one water heater or four. The assumption doing the most work in most owner budgets is that the HVAC contractor who serviced the units in spring already flagged anything critical. They usually only flagged what they were paid to look at. A separate pre-season inspection on the roof drains, the exterior hose bibs, and the crawl space vents typically runs 200 to 350 dollars and catches the things the HVAC tech walked past. Gutter clearing matters more on multifamily than on a single family house because ice dams above a shared wall can push water into two units at once, and a single insurance claim on a small building reprices the policy at renewal. On the tenant side, the one thing worth putting in writing before the first freeze is who calls whom when heat goes below the legally required minimum. Most states set that floor somewhere between 65 and 68 degrees Fahrenheit during heating season, and the clock on your response obligation starts the moment the tenant reports it, not the moment you see the message. How many of the four units share a single heating system versus each having its own, because that single answer changes almost every part of the prep sequence?
