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Overview
Basements are a planned Build Mode feature for inZOI scheduled for the Q4 2026 (October to December) timeframe per the 2026 Roadmap Part 1 letter. The feature will introduce underground floor construction, letting players build below ground level.
As of April 25, 2026, Basements have not shipped on the live build (v0.7.5). The current building system supports above-ground floors with adjustable foundation height, but does not allow constructing below ground level. The Q4 2026 update will add basement support as a complementary expansion to the existing multi-story building tools.
Confirmed Components
Component | Description |
|---|---|
Underground Floor Levels | Floors constructed below ground level. Specific number of supported underground levels has not been disclosed. |
Basement Construction | Walls, floors, ceilings, and fixtures placed in basement spaces. Compatible with existing furniture catalogs. |
Lighting and Visibility | Specific lighting model for basements (whether windows, lighting wells, or stair-down access provide visibility) has not been disclosed. |
Connection to Other Q4 2026 Build Mode Updates
Basements are part of the Q4 2026 building expansion that also includes:
Basements: This article.
Wall Decoration Modules: Interior and exterior wall decoration system.
Terrain Editing: Custom landscape sculpting (initial development).
Together these features substantially expand the construction toolkit and complete the planned 2026 Build Mode roadmap. Curved Walls (in Q3 2026) and Basements (in Q4 2026) round out the major shape and dimensional expansions for the year.
Use Cases
Once shipped, basements will enable:
Residential basement spaces (workshops, hobby rooms, home theaters, wine cellars).
Commercial basements for owned businesses (gym lower-level studio space, restaurant cellar storage, basement bars).
Storage and utility spaces that don't take above-ground square footage.
Themed basement environments (haunted house, prison cell, secret hideout) using existing decorative items.
Timeline
Date | Status |
|---|---|
December 26, 2025 | Announced in the 2026 Roadmap Part 1 letter as a Q4 2026 deliverable. |
March 26, 2026 | v0.7.0 anniversary update did not include Basements. Q4 schedule reaffirmed. |
Current target | Q4 2026 (October to December) per published roadmap. |
Open Questions
Number of underground floor levels supported (one basement only, or multi-level basements).
Whether basements support windows, lighting wells, or only artificial lighting.
Whether existing properties can be retrofitted with basements or only new builds.
Whether basements affect property value calculations or appear separately on Edit City listings.
Whether weather and natural disasters affect basements differently from above-ground floors.
See Also
Build Mode covers the current building system. Foundations and Basements covers existing foundation system. Curved Walls is the Q3 2026 partner feature. Wall Decoration Modules is bundled in the same Q4 update. 2026 Roadmap tracks delivery status.