---
title: "Extrude polygons for 3D indoor mapping | JavaScript maps SDK"
description: "Create a 3D indoor map with fill extrude height."
---
> For AI agents: a documentation index is available at [/llms.txt](https://docs.maptiler.com/llms.txt). Markdown versions of all pages are available by appending .md to any URL.
# Extrude polygons for 3D indoor mapping
Create a 3D indoor map with the [`fill-extrude-height`](https://docs.maptiler.com/gl-style-specification/layers/#paint-fill-extrusion-fill-extrusion-height) paint property.
### NPM module setup
```bash
npm install --save @maptiler/sdk
```
#### main.js
```js
import { Map, MapStyle, config } from '@maptiler/sdk';
import '@maptiler/sdk/dist/maptiler-sdk.css';
config.apiKey = 'YOUR_MAPTILER_API_KEY_HERE';
const map = new Map({
container: 'map',
style: MapStyle.STREETS,
center: [-87.61694, 41.86625],
zoom: 15.99,
pitch: 40,
bearing: 20,
antialias: true
});
map.on('load', function() {
map.addSource('floorplan', {
// GeoJSON Data source used in vector tiles, documented at
// https://gist.github.com/ryanbaumann/a7d970386ce59d11c16278b90dde094d
'type': 'geojson',
'data': 'https://docs.maptiler.com/sdk-js/assets/indoor-3d-map.geojson'
});
map.addLayer({
'id': 'room-extrusion',
'type': 'fill-extrusion',
'source': 'floorplan',
'paint': {
// See the Style Specification for details on data expressions.
// https://docs.maptiler.com/gl-style-specification/expressions/
// Get the fill-extrusion-color from the source 'color' property.
'fill-extrusion-color': ['get', 'color'],
// Get fill-extrusion-height from the source 'height' property.
'fill-extrusion-height': ['get', 'height'],
// Get fill-extrusion-base from the source 'base_height' property.
'fill-extrusion-base': ['get', 'base_height'],
// Make extrusions slightly opaque for see through indoor walls.
'fill-extrusion-opacity': 0.5
}
});
});
```
#### index.html
```html
Extrude polygons for 3D indoor mapping
```
#### style.css
```css
body {margin: 0; padding: 0;}
#map {position: absolute; top: 0; bottom: 0; width: 100%;}
```
### Basic JavaScript setup
```html
Extrude polygons for 3D indoor mapping
```
## Related examples
### [Display buildings in 3D](https://docs.maptiler.com/sdk-js/examples/3d-buildings/)
Examples
Use extrusions to display height of buildings in 3D.
### [Add a 3D model with three.js](https://docs.maptiler.com/sdk-js/examples/add-3d-model/)
Examples
Add 3D models using custom layers and three.js.