This describes how to build and control the Clan Hall.
If a clan has paid then any of its breeders can breed a clan hall by hitting the 'Clan Hall' button in the design window. This will remove the normal restriction on size based on the parents harvested bio-mass. The Clan Hall must be redesigned to use up its entire mass allowance based on the material tech.
Just like any other breeder if they are created with spawning chambers. It may be wise to build the hall for war rather than breeding in case it is attacked.
They cannot.