Houses are the second largest organizational unit within the Dark Brotherhood. They are the subdivisions of Clans, and while they have their own Summits, led by a Quaestor and an Aedile, they are still under the control of the Clan Summit. Houses are made up of the most active members within the Brotherhood. Some Houses may also have a Rollmaster, though it is normal procedure for a Clan to assign this position to only one individual for each sub-unit of the Clan.
Before the Exodus, a House was aligned to a single Order, for instance, House Oriens Obscurum of Arcona was a Sith House, whereas House Ektrosis of Taldryan was a Krath House. This is no longer the case and Houses can be made up of members of any Order, relating to the alignment of the House they are in.
Following the resignation of Grandmaster Muz Ashen, his successor Darth Pravus abolished Independent Houses, something that had been introduced to the Brotherhood by his predecessor. Every Independent House was instantly given Clan status. The units affected were: Scholae Palatinae, Odan-Urr and Tarentum.
Houses are usually divided into Battleteams, which are used differently by different houses of the Brotherhood.