Okay, did a little more experimenting. Here’s the OP’s suggestion of building again, seen from the side:
x x x x x – – – – – – –
no room | Room 4 |
– – – – – – – – – – – – –
| Room 2 | Room 3 |
– – – – – – – – – – – – –
| Room 1 |
– – – – – – –
First test, what happens when you build a stairwell room next to room 4 and above room 2?
It connects the stairwell to room 2 and calculates the cost as if building staight up (12 room points for 1 stairwell at level 3 and 4.
Next I tried going in a circle, each time connecting the new stairwell room to the top floor. This is how it looks in the top down view ingame:
– – – – – – – – | – – – – – – – – –
| Stairwell 3 > Stairwell 4 |
– – – – ^ – – – | – – – – v – – – –
| Stairwell 2 < Stairwell 1&5 |
– – – – – – – – | – – – – – – – – –
Working upwards from 1 to 4 you get an extra room “for free” ( aka 2 rooms for 6), nothing special there and you can keep going up this way until you run out of room points.
Each stairwell starts at the level of it’s number. So stairwell 1 is level 1+2, stairwell 2 is level 2+3, stairwell 3 is level 3+4, and stairwell 4 is level 4+5.
With stairwell 5 it became interesting. When going down it creates a room at level 5+4, but it also connects to the existing stairwell 1 (level 1+2), creating an extra room at level 3 at an extra cost of 6. So three rooms costing 12.
Then I figured… can we cheese the system into giving back points? So I started removing stairwell 2, 3 and 4 - in that order. Stairwell 1 and 5 remained in place including the extra room at level 3, and the recalculated cost was as if I had built straight up from floor 1 to 5.
Conclusion so far: the “extra free room” trick works, as long as you don’t come close to an existing stairwell above or below it.
A fun little experiment for me, maybe handy info for other builders. 