As has been pointed out, there are often a number of functional buildings that are attached to religious buildings. These would be where members of the Ecclesiarch live, eat and sleep as well as go about their daily lives. The type, size and number of different rooms varies hugely from place to place for all manner of reasons, but for the pruposes of this it is enough to know that there are often functional rooms or buildings attached to large religious structures such as churches (and synagogues and mosques of course!)
Again, sticking with the familiar (for me) Christian church model we touched on in the previous Research on Religious Architecture lets take a look at some spaces.
Cloisters are a necessary part of the Claustral life of monks (or nuns) as it allows them to live within the enclosure and apart from others. As such, cloisters attached to churches or cathedrals show that the building is (or was) part of a monastic foundation, acting as places for quiet meditation or study.
The Vestry is a small room which is part of, or attached to the main religious building. Not only is this a place where vestments are kept and donned for services, but it is also a place where records, books and vessels etc. can be kept.
Historically, the churches administrative committee (also called a vestry) would have held closed or private meetings in the same room.
A vestry is not to be confused with a Chapter House.
Other rooms or buildings in large establishments can include places such as a School, Library or Treasury. However, even after a quick look at this, you can see that a fully functioning "Imperial Shrine" or cathedral-like building, is likely to have a number of accompanying buildings associated with it. This means I'm going to need to plan some appropriate buildings!