High-rise pour in November 2026: will porta potties freeze on floor 20?

Yes, standard portable toilets will freeze solid on floor 20 in Chicago in November. The holding tank and deodorizer are water-based and will turn to ice in high winds and sub-freezing temperatures, making them unusable. You need winterized units with antifreeze added to the tank. Specify this to your rental company, they should use a non-toxic antifreeze solution, often brine-based, to prevent freezing down to about -20°F. For 50 workers per shift, OSHA 1926.51 requires two units (one toilet seat and one urinal per 40 workers), so your plan for a cluster with one ADA-compliant unit and one standard unit meets the minimum. Service weekly is standard, but in cold weather with 50 users, expect faster filling and potential odor issues; discuss a mid-pour service if the crew complains. Since crane lifts are costly and disruptive, aim for a single delivery and pickup, with the rental company prepping the units for three weeks of use. Avoid flushing units or handwash stations, their fresh water tanks freeze easily and are not practical here.