Upgrade path

Wood Cellar Door→ 1× Iron Cellar Door →Iron Cellar Door→ 1× Steel Cellar Door →Steel Cellar Door

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

Crafting

Craft at Workbench · makes 1

Harvest drops

Taken apart with a harvesting tool (axe, pickaxe, shovel), before perks and tool bonuses.

Salvage drops

Extra parts when salvaged with a wrench, ratchet or impact driver.

When it collapses

Falling, it leaves Scrap Metal Pile (75% of the time) where it lands.

Where to find (3 POIs)

Judy Witch (tier 4), Church Of The Blinding Faith (tier 3), The Curren Residence (tier 2).

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