It depends on what kind of plastic the housing is made of. If it's PVC, CPVC, Styrene or Acrylic, solvent cement can be used to glue it. If it's Nylon, Polyethylene or Polypropylene, no glue will hold for long. The reason that it broke might be that the plastic has degraded from sunlight. All plastics degrade somewhat, but some are worse than others. PVC, Polyethylene and Polypropylene are among the worst. Light colors degrade before black. If the plastic has become brittle, the repairs are likely to be less than satisfactory.