Crushing weight of wood?

[⛩️ BOT Mushin ⛩]

While placing a wooden floor 1 level higher than the ground floor our outdoor keep, I decided the color was too bright for my gabbro walls so I marked them for removal to try again.

The unfinished roof upon being removed collapsed, killing one of my dwarves because I am a noob.

Now all of this is normal fortress stuff until I realised his body pierced through 11 levels of the keep, 2 clay and 9 stone.

Is this normal? x'D

[Philtre]

Originally posted by ⛩️ BOT Mushin ⛩:

Now all of this is normal fortress stuff until I realised his body pierced through 11 levels of the keep, 2 clay and 9 stone.

Is this normal? x'D

Cave-ins will keep going until they hit a fully-supported tile, so if you had dug out the corresponding area on each of the 11 levels under the cave-in site, yes, it's normal.

[Guided]

it can happen yes :(

when you remove, make sure you only have one dwarf doing it.
as they remove or channel above an open space, be shore to only select the edge, but NOT any corners
for example, if it leaves a diagonal tile, it will fall.

so

if you did something like this

xxx
oox
oox
the dwarf may mine out the two sides as he stands at the corner, leaving the very top right x until last, so it will fall

so long as there is something to attach a tile via the north, south,east, west, it will not fall

there is actually a way to break through an aquifer using this mechanic

[Sudo Modding]

Cave in are absurdly dangerous, but I guess it's normal in dwarf fortress. Indeed a simple wood floor can crush through dwarfs and stone floors like butter (it happened to me through several fully supported stone tiles).
Your best bet is to avoid them at all cost in the future, always micro manage them by making sure there's always 1 tile next to each tile.
And don't expect your dwarfs to be clever enough to remove a complete floor safely, they'll do the exact opposite.
Even if you use priorities. The only way is to remove the floors 1 tile width at a time.

For comparisons:
- I had a dwarf that removed 1 construction stair, not supported on the side, 1 level above ground -> cave in, dead
- I have a trap that start by dropping the goblins 10 levels down -> they don't have a scratch and are barely stunned

So cave in = df nuke. That also must be why it's used to kill almost unkillable monsters (eg beasts made from sturdy metals)