Spiral Stairs

Spiral Stairs are a compact stairwell design used in Timberborn to allow beavers to traverse multi-story buildings efficiently. The design appears in the game's stairs category and was introduced in Version 1. The term is rendered in Chinese as 木楼梯 in some sources. Spiral Stairs are represented in the game's gallery by several artworks and example images showing typical 2x2 spiral layouts.

Spiral Stairs are valued for vertical compactness and fast construction when building tall structures. The commonly used 2x2 spiral stair configuration built with platforms is the most compact and fastest-to-build method for gaining height. An alternative 2x2 spiral uses Overhang 2x1 pieces; this variant is functional but slower to build and consumes more materials.

• To construct the fastest 2x2 spiral using platforms, start with two single Platform pieces placed in opposite corners at the base. Above those, continue with Double Platforms stacked up to the desired height to form the spiral shaft.
• If you need an intermediate exit from the staircase (a landing or rung partway up), the strict 2x2 spiral pattern must be altered. Creating a mid-way egress typically requires adding overhangs or breaking the repeating platform pattern to provide horizontal access to rooms or ledges.
• The 2x2 spiral built with Overhang 2x1 pieces provides the same compact footprint but increases build time and material cost compared to the platform-based spiral.
• Visual references for spiral stair layouts and variations exist in the game gallery, showing both platform-based spirals and overhang-based spirals.

Spiral stairs are a practical solution when space is limited and rapid vertical access is required. They are especially useful in tall, narrow towers or when multiple stories are needed without expanding the building footprint. General historical trivia about spiral stair structures outside the game notes an ancient spiral staircase discovered in China dating to 5378 BC and mentions of spiral staircases in the Old Testament reference to the Temple of Solomon, but these notes are contextual and separate from the in-game design history.