November 2026: Will a high-rise porta potty freeze on the 15th floor?

A standard portable toilet on the 15th floor will not freeze solid overnight in 40°F Phoenix temperatures. The holding tank contains waste and deodorizer solution, which has a lower freezing point than water due to salts and organic matter. In my experience, units start having issues below freezing, not in the 40s. For a crew of 20, OSHA 1926.51 requires one toilet, so your unit meets the minimum. Since it's a long-term rental with weekly service, confirm with your rental company that they use a winter-ready formaldehyde-free deodorizer which often includes antifreeze properties. They should handle this as part of standard winterization for cold climates, but it doesn't hurt to ask. No heater is needed at these temperatures. Just ensure the crane lift is scheduled for service days so the driver can access it, blocked units result in missed service trips that you may be billed for.