Duplexes (also known as semi-detached homes) offer an affordable
housing alternative to a detached house. Duplexes are buildings that
consists of two dwelling units, one above the other under the ownership
of a single person. Usually each unit has each own separate lot and
entrance. Halifax historically enjoyed low housing prices so triplexes
were not built. Most residents prefered single family detached homes.
With the recent raise in housing starts this may change.