Heat Tape for Frozen Pipes: Do It Safely

Use the right product

Choose self-regulating heat cable listed for pipe freeze protection (look for a UL or ETL listing). Self-regulating cable reduces its output as the pipe warms, so it's much less likely to overheat than older constant-wattage tape. Replace heat tape that's more than a few years old, cracked or discolored.

Plug into a GFCI outlet

Heat cable must be on a GFCI-protected outlet (many cables also have built-in protection). If you don't have an outlet near the pipe, have an electrician install a GFCI receptacle rather than running an extension cord through a crawl space.

Common installation mistakes

• Overlapping or crossing constant-wattage tape over itself (overheats)
• Wrapping insulation over tape that isn't rated for it
• Using it on plastic pipe when the product is rated for metal only
• Leaving it plugged in all year
• Using indoor extension cords in damp areas

Other ways to prevent frozen pipes

Insulate exposed pipes, seal drafts in the rim joist, keep the garage door closed and open cabinet doors on exterior walls during deep cold. For a pipe that freezes every year, a dedicated GFCI circuit with a thermostat-controlled cable is the long-term fix.

Need a GFCI outlet near your pipes? →