In areas with a winter design temperature of 32°F or lower, where must a water, soil, or waste pipe not be installed to avoid freezing?

In areas where the winter design temperature drops to 32°F or lower, it is critical to avoid installing pipes in locations where they are vulnerable to freezing. Outdoor installation of water, soil, or waste pipes exposes them directly to the external cold, leading to a higher risk of freezing. When water freezes in pipes, it can expand and cause the pipes to burst, resulting in costly repairs and potential water damage.

While pipes installed in walls, attics, or under sinks can present a risk of freezing, these areas might be insulated or heated to mitigate that risk. For example, interior walls may offer some degree of temperature regulation due to indoor heating. Similarly, attics may be subject to slight warmth from the home’s internal temperature, especially if ventilation is adequate. Under sinks can often be kept warm by the ambient air of the living space or may be modified with insulation.

In contrast, pipes installed outside are fully exposed to subfreezing temperatures without any insulation or warmth from the living spaces, making this installation method the least advisable in cold climates.