Feature request title:
Phased construction, or staged construction plans
This would allow construction to be done in discrete sections, as though from a Gantt chart. So, for example: I could create a plan for some building; I then mark those changes as “Phase 1”, and switch to a view showing the finished construction. I can then build on-top of this “finished” construction, mark those changes as “Phase 2”, and continue to the pattern up to some limit.
Although materials for all phases can be delivered at once, contractors will not work on Phase 2 changes until Phase 1 is completed.
Why it should be implemented:
a) Realism. In real life large construction projects are planned and executed like this. It looks a bit strange to build the internals to a room before the walls are up, for example.
b) Convenience. There are often cases where I’m forced to wait for construction to finish before I can start building the next step. This is both annoying (as a player, I want to design the construction plan and then just leave contractors to get on with it) but also means that I can be forced to wait for materials to arrive. In particular: creating taxiways is very two-phased at the moment: I create the taxiway foundation, and then have to wait for that to finish before I can actually build the taxiway routes. With this implemented I could have the foundation as Phase 1, and the then actual taxiway routes as Phase 2.
c) Splitting a project up to avoid other issues. Let’s say I want to move where the baggage claim is and repurpose that space for shops. Currently I have to 1. Build the new baggage claim; 2. Reroute baggage to the new one. 3. Remove the old one. 4. Build the shop. If I try to do this all at once I may end up with non-functional baggage systems for a bit. This is not good. I’ve also managed to accidentally trap people in spaces because of the building orders. When building secure zones it would also be good to be able to build the incoming security before building the doors to the ramp areas.
In general, this whole thing could make executing large building projects much more feasible.
And - worst case - if someone doesn’t want to bother with all this, they can continue to do single-phase building exactly as it currently works.