It is 2 units that have previously been connected into one duplex or townhome.  The owner of such a unit is considered as owning 2 shares of stock.  An owner of a double unit pays a maintenance fee on each "half" of the unit.  Utilities are also calculated on each "half".  At present, there are 28 double units.

When an adjacent home becomes available, many people consider buying it to make into a double unit.  All renovations necessary to connect 2 units must be approved by the board of directors.