Is the Stair huts 3D model free for commercial use?

Yes. It is free under the 1DesignTool 3D library license: use it in personal and commercial work — games, apps, websites, renders, ads and client projects — and modify it as you like, with no credit required. What you can't do is re-sell or re-distribute the file on its own or inside a model pack.

What file format is it, and how big is it?

A single binary glTF 2.0 file (.glb), 55 KB: 592 triangles, 1,776 vertices and 16 materials, modelled in metres at 3.1 m × 3.4 m × 4.0 m.

Can I animate Stair huts?

It ships as a static mesh. Its 6 named parts are separate nodes, so you can move or animate each one in your engine.

Which engines and tools can open it?

Anything that reads glTF 2.0. three.js, React Three Fiber, Babylon.js, Godot 4 and Blender import the GLB directly; Unity and Unreal Engine load it through their glTF importers. The snippets above show the exact code for three.js, React Three Fiber, Godot and Blender.

How was the Stair huts 3D model made?

Claude Code (Claude Opus 5.5) generated it inside 1DesignTool's 3D template from a written brief, then the design kit's checks verified the geometry and the GLB before it was published. You can make your own the same way with 1DesignTool.

FREEcommercial use · no sign-up

Stair huts

A low-poly rooftop stair hut: a small brick bulkhead with a sloping tar roof behind a coped parapet, an orange steel door with a lamp, high side windows, a back louvre and a roof vent. It is a modular piece that snaps on a 1 m grid.

Original GLB55 KB Poster

Left rail: colours and the 3 knobs the agent wrote into this model — they rebuild the geometry and go into your download. Right rail: looks for the viewer. Drag to orbit, scroll to zoom.

Triangles: 592
Vertices: 1,776
Meshes · materials: 16 · 16
Size (W × H × D): 3.1 m × 3.4 m × 4.0 m
File: GLB · 55 KB
Animation: Static
Style: Low-poly
Collection: Rooftop District

Palette · named materials

brick red: walls and parapet#c32222
brick red dark: plinth, corner piers, louvre lintel#821717
brick red light: string course under the parapet#db5757
tar grey: roof membrane#757e8a
tar grey dark: door threshold and kick plate#525860
tar grey light: parapet coping and window sills#a3a5a8
sunset orange: steel door leaf#ed7e1d
warm white: door and window frames, lamp lens#f2ede2
soot black: window panes, handle, lamp, stack, louvre frame#1b1b22
mid grey: roof vent and louvre slats#7d828c

Use it

import { GLTFLoader } from "three/addons/loaders/GLTFLoader.js";

const gltf = await new GLTFLoader().loadAsync(
  "https://assets.stoicsoft.com/1designtool/3d/models/rooftop-district-stair-huts/ec6cfe1301/model.glb"
);
scene.add(gltf.scene); // metres, +Y up, front faces +Z

How it was made

The brief given to 1DesignTool's “3D object” template:

Stair huts for the Rooftop District kit. Design it as one clear asset at believable real-world scale for that setting (state the size in metres in meta.notes), with its main parts modelled and named, readable at thumbnail size and from every orbit angle. It is a modular piece that snaps on a 1 m grid: give it a length in whole metres and put the origin at its snapping end, stated in meta.notes. This is one part of the Rooftop District kit (Low-poly style, flat-lowpoly direction): Life above the streets. Use ONLY the kit palette, by name: brick red #c32222, tar grey #757e8a, sunset orange #ed7e1d, water-tower brown #6b4a2e, brick red dark #821717, tar grey dark #525860, brick red light #db5757, tar grey light #a3a5a8, soot black #1b1b22, warm white #f2ede2, mid grey #7d828c, dark wood #3d2a1c. Every material's `name` must be exactly the palette colour it uses — the GLB carries these names so the kit recolours as one; an unnamed material fails delivery. Kit knob: expose a param `skylineHeight` (0–1, default 0.5) for the kit's "Skyline height" setting wherever it makes sense on this part, and keep that id.

Agent: Claude Code · Claude Opus 5.5 in 1DesignTool
Direction: Low-poly · family scenes
three-check PASS · glb-lint PASS

Make your own with 1DesignTool →

Named parts · 6

Stair hut
Brick body
Parapet coping
Roof and vent
Door and lamp
Windows and louvre

Note: Size at defaults: 3 m wide (X) by 4 m long (Z) by 3.33 m tall at the door-end coping, 3.4 m to the top of the roof stack. The roof falls 20 cm per metre toward the back. Grid snapping: the footprint is exactly width x length whole metres (the coping edge is the footprint line, brick faces sit 5 cm inside it, nothing passes it). The origin is at the bottom centre of the door end, which is the snapping end; the door faces +Z and the hut runs back along -Z, so the model's centre is at z = -length/2, not at the origin. It rests on y = 0. The exported model has 592 triangles in 16 meshes, and the count does not change with the params. Every material is named exactly after a kit palette colour; 10 of the 12 are used (water-tower brown and dark wood are not). Some colours appear as one material per part, so the GLB holds 16 materials with 10 distinct names. The model is static, with no animation clip. Params are baked into the GLB at their defaults and only change the model when the scene is rebuilt in the viewer. skylineHeight (the kit's 'Skyline height') raises the door-end wall from 2.85 m at 0 to 3.65 m at 1. length and width step in whole metres (3-6 and 2-4). Both all-min and all-max param sets were rendered and passed three-check. glb-lint: 0 errors and 6 heuristic warnings: more materials than the direction's default of 10 (the same palette colour per part), duplicate material names, non-indexed geometry (deliberate flat shading), brick bands nested through the wall mass, the coping resting on the parapet in a separate part group, and a height of 3.4 m against the direction's 1 m reference. Its verdict reads UNVERIFIED only because no host requirements contract was supplied. plan-check passes except for its part-id regex, which rejects the hyphens in the slug-based ids this library requires; three-check accepts them and all 6 survive the GLB reload.

About the Stair huts 3D model

Stair huts is a free low-poly 3D model from the Rooftop District set. It measures 3.1 m × 3.4 m × 4.0 m (W × H × D) at real-world scale and is built from 592 triangles across 16 meshes, with 6 named parts. Download the 55 KB GLB and drop it into three.js, React Three Fiber, Godot or Blender — free for commercial use, no attribution required.

Is the Stair huts 3D model free for commercial use?: Yes. It is free under the 1DesignTool 3D library license: use it in personal and commercial work — games, apps, websites, renders, ads and client projects — and modify it as you like, with no credit required. What you can't do is re-sell or re-distribute the file on its own or inside a model pack.
What file format is it, and how big is it?: A single binary glTF 2.0 file (.glb), 55 KB: 592 triangles, 1,776 vertices and 16 materials, modelled in metres at 3.1 m × 3.4 m × 4.0 m.
Can I animate Stair huts?: It ships as a static mesh. Its 6 named parts are separate nodes, so you can move or animate each one in your engine.
Which engines and tools can open it?: Anything that reads glTF 2.0. three.js, React Three Fiber, Babylon.js, Godot 4 and Blender import the GLB directly; Unity and Unreal Engine load it through their glTF importers. The snippets above show the exact code for three.js, React Three Fiber, Godot and Blender.
How was the Stair huts 3D model made?: Claude Code (Claude Opus 5.5) generated it inside 1DesignTool's 3D template from a written brief, then the design kit's checks verified the geometry and the GLB before it was published. You can make your own the same way with 1DesignTool.