Since last time i saw such a thread i saw one spawn on a plateau.
So the plateau seem not to protect 100 %
(No workbench range at that time so far i remember)

No idea what is about Workbenches and how good houses protect (never saw a spawn inside a house)

But maybe i have so few (or non in general) spawns is because i build not on spawns. One of the things i demand to build somewhere is that there are no enemys arround. or with other words, if ou need to defend yourself during you build the spot is not good