A tubing hanger is a device used to suspend a wide variety of tubing and duct work off of the ground. Commonly hung from a framework beam or the roof of a structure, the tubing hanger is fully adjustable to allow the tubing to remain level or on a slight grade even though the framework or structure is not on the same grade. Commonly manufactured from a metal band connected to a threaded rod, the tubing hanger is attached to the hanging surface by nuts and washers. With certain tubing hanger construction, the clamp component of the hanger is used as a cradle with the tubing running loosely through it, while other designs use a tightening clamp that is tightened to the tubing to protect against any movement.
In some small areas, a tubing hanger may be constructed of a steel banding being screwed to a floor joist on both ends while the tubing rests in the resulting bow in the strap. This style of hanger is not recommended, however, for tubing and lines carrying pressurized gasses or liquids. Pressurized lines often jump around as the pressure is removed and applied. This results in bumping and rattling throughout the structure where the unrestrained tubing hangs. This is also a prime example of where the tightening style of tubing hanger should always be used.
Most building codes will dictate where all tubing hanger suspension devices are to be installed. Failure to heed the required spacing and style of hanger used can cause the inspector to halt any work on the site until the hangers are brought up to code. Some hot water pipes even require insulated hangers while other lines require such features as rubber-lined or galvanized hanger clamps. The diameter of the hanger's threaded rod can also be mandated by code depending on the type of line being supported, the type of structure the line is being installed in as well as the geographic location of the build site.
One of the most common lines to cause bumping and noise distraction is a cold water supply line. As the temperature of the water inside the line changes, the pipe will actually expand or contract. This often is the cause of loud banging sounds coming from underneath floors or in overhead ceilings. A common fix for this type of problem is affixed tubing hangers tightly attached to the structure by means of a movable hinge or rubber support. The hinge, be it a common hinge or a rubberized version, allows the tubing hanger to move freely and quietly as the pipe changes length.