Review on 🔥 Efficient Pipe Heating Solution: M-D Building Products 64428 Md Pipe Heating Cable With Thermostat, 18 Ft, Red, -50 Deg F by Dan Cramer

The chart on the back shows the recommended lengths for various pipe types from 1/2" to 1". It worked well at temperatures < 0 F on a much larger pipe when tightly wound. I precalculated the length of the ribbon for each spiral by multiplying the tube diameter * 3.1459 (pi). The number of spirals by taking the total length of the pipe and dividing it by the spacing you want (which is what I guessed). Estimated length by dividing the number of spirals by the length of each spiral. Walk in and everything worked great. I did everything in inches and then converted to feet as a final step.