Inverted constant force window balance having slidable coil housing

An inverted constant force window balance system comprising:

• a carrier assembly comprising:
• a housing comprising a first housing wall and a second housing wall substantially parallel to the first housing wall;
• a coil spring disposed within the housing, the coil spring comprising a free end;
• and
• a shoe assembly slidably coupled to the housing,
• wherein the shoe assembly comprises a first shoe face and a second shoe face substantially parallel to the first shoe face,
• wherein the housing is configured to slide between a first position and a second position relative to the shoe assembly,
• wherein when in the first position, the first housing wall and the second housing wall are substantially non-coplanar with the first shoe face,
• wherein when in the second position, the first housing wall is substantially coplanar with the first shoe face and substantially non-coplanar with the second shoe face, and
• wherein the shoe assembly is configured to receive a pivot bar from a window sash and extend at least one brake upon rotation of the pivot bar;
• and
• a mounting bracket releasably coupled to the housing opposite the shoe assembly and coupled to the free end of the coil spring.