Coated fibrous pipe insulation system

The subject invention relates to a pipe insulation system and in particular, to a pipe insulation system that includes a tubular core of fibrous insulation coated with a polymer that is especially well suited for insulating cold pipe systems. A pipe insulation system includes a tubular core of fibrous insulation that is coated with a pliable polymer. The coated tubular core has a first longitudinal slit extending completely through the wall of the core and a second longitudinal slit in the inner surface of the tubular core that is opposite the first slit and forms a hinge that permits the tubular core to be opened and closed to place the coated tubular core about a pipe. Preferably, the coating has a water vapor permeance rating of 0.02 perms or less and the system includes a seal for sealing the first slit so that an outer surface layer of the sealed coated tubular core formed by the coating and seal has a water vapor permeance rating of 0.02 perms or less for use on cold pipe systems.