A. Felix Marti responds: We have had to deal with this exact situation. We work in a mountain region with elevations between 8,000 to 10,000 feet, and frost depths from 4 to 5 feet. We detail the pipe as follows, and so far we have not been called back to repair a burst waterline.
While the trench is open and the water line is being plumbed into the house, we insulate the pipe all the way to the bottom of the trench. There are several pipe insulations available. We typically use Rubatex — a rubber-based, closed-cell foam insulation (Rubatex, 906 Adams, Bedford, VA 24523; 800/782-2839), or Owens-Corning SSL-2 fiberglass...
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