Upgrade path

Siding White Burnt Center Plate→ 4× Wood →Window Plug 03→ 10× Cobblestone Rocks →Cobblestone Block→ 10× Concrete Mix →Concrete Block→ 10× Forged Steel →Steel Block

Hit a placed block with a stone axe, claw hammer or nail gun while carrying the material of the next step: 4 hits per upgrade.

Where to find (1 POIs)

The Crisp Residence.

Points of interest built with this block (any of its variants), the highest tiers first, from the game's prefab files.