Updated July 2026
Build Mode Controls in SCP Architect X
Build mode is where SCP Architect X stops feeling like a walking simulator and starts feeling like a foundation architect sim. Every containment cell, staff break room, and server hall begins as a ghost preview in Place Mode. This guide goes deeper than the general controls overview and explains how each build toolbar button maps to keys, how placement submission works, and how advanced players chain shortcuts for efficient megabase construction.
Place Mode Interface and Categories
Enter build mode with B. The Place Mode sidebar organizes content into categories such as walls, doors, power, furnishings, and—after research—specialized containment equipment. Use the search fields at the top left to filter wall packs or individual objects when your inventory grows cluttered. Press 1 at any time to collapse or expand this sidebar, giving you a clearer view of large footprints like cafeterias or warehouse wings.
Selecting a wall pack loads its pieces into your active hotbar list beside the categories. Each piece previews in semi-transparent green when placement is valid and red when colliding with obstacles or lacking foundation support. Some packs are cosmetic variants of standard foundation tiles; others include reinforced segments needed near high-risk anomalies. Switch packs before submitting if you notice the wrong material—undo is cheaper than demolishing finished rooms.
The Placement Workflow: Move, Rotate, Submit
After picking an object, click or use the placement key to spawn a preview anchored to your cursor grid. M switches into Move Placement, letting you slide the preview without re-selecting from inventory. R and T handle clockwise and counterclockwise rotation. Fine rotation matters for door clearance, desk-facing in observation rooms, and aligning Tesla Gates (after research) with choke points.
F submits the placement. Until you press F, the game treats previews as temporary and will not charge build costs or block NPC pathing. Chain placements by keeping the same inventory item selected: submit one tile, move, rotate, submit again. This rhythm is how speed builders lay hundreds of foundation tiles per session. If submission fails silently, check funds, research locks, and floor level—elevators require Multiple Floors and cost $5,000 each.
Delete Mode, Undo, and Redo
Hold G or activate delete mode from the upper-right toolbar to remove individual tiles. Delete mode highlights targeted pieces in red. It is best for surgical fixes—removing a single misplaced door—rather than wiping entire wings. For wider errors, Ctrl+Z undo stacks are faster and less error-prone.
Ctrl+Y redoes actions you accidentally undone. Together they form a safety net when experimenting with experimental layouts like dual-layer observation decks or stacked server rooms. Note that undo history may reset when leaving build mode or reloading a save slot, so finalize major layout milestones before closing the session.
Advanced Building Mode and Gamepass Tools
The Advanced Building button on the upper-right toggles precision tooling available to Advanced Building gamepass owners. This mode typically exposes finer grid snapping, extended copy tools, or mirrored placement—exact features can vary by update, but the intent is reducing repetitive clicking for large symmetric sites. Players without the pass still have full access to standard rotation and undo shortcuts.
Delete mode and Place Mode share the 1 key in some contexts depending on focus; if toggling behaves unexpectedly, click the explicit toolbar icon once to resync state. When planning multi-floor layouts, ascend with Shift+E before submitting upper-floor tiles so previews align with the correct Z-level.
Pro Tips for Faster Construction
Build containment modules as repeatable units: three walls, one door, one observation window, one Lab Station cluster. Clone the unit with multi-select and Shift where supported. Route power and basic-needs closets before hiring staff so NPC pathing validates early. Place Test Subject Zones adjacent to Lab Stations to minimize Class-D walk time, which directly affects gross profits on your economics report.
Exit build mode only after pressing F for all pending previews. Run a quick walkthrough in live mode to confirm staff can reach cafeterias, medbays, and anomaly desks. If paths fail, re-enter with B and adjust before scaling hiring. Pair this routine with the facility layout guide for research-gated items like elevators and Tesla Gates.
Frequently Asked Questions
What is the difference between Move Placement (M) and clicking to place?
Clicking drops a preview at the cursor grid. M lets you reposition an already spawned preview before submission, which is useful when aligning long wall runs without re-selecting from inventory.
Can I rotate objects after submitting them?
Generally no—you must delete or undo and re-place. Ctrl+Z is the fastest fix for a single mis-rotated door. For furnished rooms, deleting may disrupt staff assignments, so rotate carefully before pressing F.
Why cannot I place elevators or staircases?
Multiple Floors research must finish first ($22,000, two hours). Staircases unlock immediately after research; elevators appear in the basic-needs or structure catalog and cost $5,000 per placement.
Does build mode pause staff simulation?
Behavior can vary by beta patch, but many players report reduced or paused NPC activity while actively editing. Do not rely on build mode as a pause for riots—hire security and stabilize needs before large construction projects.
How do I search for a specific wall pack quickly?
Use the wall pack search field in the top-left of Place Mode. Typing partial names filters huge cosmetic libraries down to the pack you unlocked from achievements or donations.