Word for a set of small side tasks that must happen before the primary tasks can continue

Question

As an example someone is adding two additional rooms to a house. They finish the first room, but before they can start building the second -- they need to schedule an inspection, file paperwork, pick up supplies, etc.

In a sentence:

Before we can continue construction, we have some ????? tasks to do.

Construction is the main task, however these other smaller but necessary tasks must happen before construction can resume.

"Interim tasks" almost works, but doesn't emphasize that these tasks must be done before progress can continue. "Blocker tasks" also kind of works, but seems to imply that these smaller tasks are problems that were unexpected despite being predictable from the start.

Answer 1

intervening:

happening between two times or between other events or activities.

Answer 2

The word preliminary might work:

coming before and usually forming a necessary prelude to something else

(source: Merriam-Webster)

Preceding or done in preparation for something fuller or more important.

(source: Lexico)

I think it captures both the necessity and the not being the main tasks.

If you need something that captures the 'in between', you might try impeding but it has less of a 'necessity' feeling.

Answer 3

I'm going to suggest

Prerequisite

something that must exist or happen before something else can exist or happen

Prerequisite tasks are subtly implied they are not the main task, but if you need to make it clear that these tasks are not the primary or main task you could say prerequisite minor tasks or prerequisite secondary tasks.