Simple Indoor Tagging

Simple Indoor Tagging is a tagging schema for Indoor Mapping. It is simple to use but still holistic to even cover complicated cases. A list of other/previous indoor tagging schemes can be found here. This document was created in 2014 by SimonPoole, Tordanik, Peda and Andi; and primarily written for mappers.

Summary

To sum up, these are the main characteristics of the model:

• mapping of indoor spaces including different floors (alias levels)
• existing OSM methodologies (nodes, ways, relations and keys) are utilized

Compatibility with Simple 3D buildings (S3DB) is an explicit goal of Simple Indoor Tagging (SIT). When combining SIT with S3DB, tags from both should be used at the same time.

Use cases

See also: indoor/use cases

Indoor maps or 3D indoor information can be used for various applications, e.g.

• Indoor navigation/routing: see the guidelines for pedestrian navigation
• Floor plans and 3D maps
• Public participation
• Emergency response

for public buildings.

The model / tagging schema

In the following section, the model is presented and described

Simple POI mapping

Illustration of simple POI mapping

Mapping of objects in OSM works best when there is no upfront requirement to immediately add everything in great detail. Most of the time mapping progresses from rough to detailed to insane. To support this we need to define a simple POI mapping scheme that can be used together with the indoor schema to allow visualisation and routing even when detailed floor plans are not available.

One approach is to allow such nodes simply to be tagged with a "level" tag. To make this simple enough to consume we suggest that either on the building outline or on the building relation at min_level=* and max_level=* should be tagged.

In the simplest case this would require only the addition of 2 tags to the building polygon and level tags to the POIs for a rough visualisation to work (routing would not be supported without additional indoor elements).

Key	Description	Example value(s)
level=*	the level the POI is located on	level=3, level=-1

Building

To make it easy for data consumers to find buildings with indoor coverage we suggest the tags min_level=* and max_level=*. In some countries specific level values are not assigned, e.g. floor 13 in western countries or floor 4 in East Asia. To make these cases easier to map, we propose non_existent_levels=*.

Key	Description	Example value(s)
min_level=*	minimum indoor level	min_level=-1
max_level=*	maximum indoor level	max_level=14
non_existent_levels=*	optional: levels which don't exist e.g. for regional reasons	non_existent_levels=4;13

Modelling the different indoor elements

The different indoor elements of a level also need to be mapped in OSM. Thereby, those parts with a covered area (i.e. rooms, stairways, corridors) are mapped as areas (closed ways or multipolygons).

We propose four basic indoor elements, with which everything can be modeled. The 5th value indoor=level is optional and not intended for rendering purposes, but for having a place to add additional information like a floor name.

Illustration of the 4 basic indoor elements

Key	Value	Element	Description
indoor=*	room		Conventional room with walls. Purpose of the room can be described by room=*
indoor=*	area		Area without walls (usually a subdivision or a room)
indoor=*	wall		Individual (non-passable) wall element, when not already defined by indoor=room
indoor=*	corridor		Enclosed walkway area that connects rooms
indoor=*	level		Can optionally be used for advanced modelling of building levels

The individual areas share the same nodes where they share a wall in real world. Connections between rooms are mapped with door nodes, see that section for details.

Doors and windows

Doors are mapped as nodes. A door node is shared between the rooms which the door connects and by the wall way (if any). Doors which are entrances to or exits from the building are additionally tagged as entrance=*.

Key	Value	Element	Description
door	yes		Door of unknown type
	no		Opening in the wall which allows passage but is not covered with a door
	*		Door of a particular type, see Key:door for possible values

Windows are similarly mapped as nodes in walls, room outlines and building outlines. They can exist both in interior and exterior walls.

Key	Value	Element	Description
window	*		Location of a single window (or vertical column of windows if used with repeat_on=*)

It is possible to add additional tags to describe a door or window in detail. Tagging standards for these are proposed and documented separately from Simple Indoor Tagging. Refer to, for example:

• Proposed features/door
• User:Tordanik/Window tagging

Modelling connections between different levels

Stairs and escalators are modeled the same way as above. They span multiple levels (level=-1-5) and are connected to indoor=corridors via a door=* node on each floor. door=no can be used to tag a connection to a corridor when no physical door is present.

A uniform staircase or classic elevators would lead to duplicate door nodes in the same way. The nodes are also at the same lat/long coordinates, only differing in the level value. For these cases we recommend to use only one door=* node with multiple level values or ranges, e.g. repeat_on=1;2 or repeat_on=1-5 (more see below). We recommend consumers of indoor data to duplicate these objects during preprocessing, using one level value for each.

Photo	Use case	Proposed tagging
	Stairs	stairs=yes indoor=room or indoor=area when there are no walls.
	Escalators	stairs=yes conveying=yes indoor=room or indoor=area when there are no walls.
	Elevators	highway=elevator indoor=room or in special cases indoor=area when there are no walls.

Use a semicolon to separate the levels covered by the stairs, escalator, or elevator, or define a level range. For example, level=0;1 or level=0-1 could be used on some stairs that connect levels 0 and 1. Stairs connecting levels 2 and 4 would be tagged level=2;3;4 or level=2-4 – regardless whether level 3 can be accessed from these stairs. Also see the section on #Multi-level features and repeated features.

Advanced modelling of the different levels (floors)

Sketch for a slightly more complicated example using building:parts

All elements on the same level get a level tag or are optionally member of a level relation.

Key	Description	Example value(s)
level=*	Describes on which level the element is (0 is normally the ground-level, -1 is the first basement etc.)	level=0, level=-2, level=3

Local level notations per building should be reused. e.g. at Munich Airport, 3 is the ground level.

Reasonable and sensible keys and values which could be added to an optional level-outline (indoor=level) are mentioned in the following table:

Key	Description	Example value(s)
name=*	the name of the corresponding level	name=Ground floor
level:ref=*	the number or code of the level. This models the level numbering scheme as it is displayed in the building itself, e.g. on floor plans or elevator buttons, which may be different from the level=* value.	level:ref=K level:ref=E level:ref=3
height=*	the height of the level (with default unit meter)	height=4
level=*	describes which level number the current level has (0 is normally the ground-level, -1 is the first basement etc.)	level=0, level=-2, level=3

Information about the indoor elements themselves (e.g. a name or type) are again attached as key-value pairs to the corresponding indoor element.

Key	Description	Example value(s)
level=*	MANDATORY the level the indoor element is located on	level=111, level=-1
name=*	the name of the indoor element (e.g. the room name)	name=Vesalius Aula, name=Audimax
ref=*	the ref of the indoor element (e.g. the room number)	ref=101, ref=01.15
height=*	individual height of an indoor element (default unit is meter)	height=3, height=2.5

Multi-level features and repeated features

Key	Elements	Description	Example value(s)
level=*		in addition to the previously described cases, features spanning multiple levels (e.g. stairs, elevator shafts, high rooms) can be mapped by listing more than one level in the value	level=1;2, level=-1-5, level=-4--2
repeat_on=*		features that have identical copies on other floors can be mapped as a single node with this tag. This should be used sparingly and only if it is necessary (often the case with windows and elevator/staircase doors). The starting level is not included in this list, e.g. a feature with level="0" then repeat_on starts with "1".	repeat_on=1;3, repeat_on=0-6

Additional example images

As the text above should stay consistent, and big changes should be coordinated with the original authors (see above), examples from third parties can be added here:

Tagging examples

Location	Building	OpenStreetMap	OpenLevelUp	indoor=
🇦🇷 Buenos Aires	Museo Nacional de Bellas Artes (Fine Arts National Museum)
🇦🇺 Sydney	Central (railway station)
🇦🇹 Vienna	Südtiroler Platz
🇨🇴 Bogotá	Catedral Primada de Bogotá
🇪🇨 Quito	Quicentro Shopping
🇫🇷 Paris	Gare de l’Est Train Station
🇫🇷 Paris	Palais du Louvre
🇫🇷 Paris Xème	Gare du Nord
🇫🇷 Paris XIIème	Gare de Lyon
🇫🇷 Paris Xvème	ECE-Paris
🇫🇷 Clermont Ferrand	Centre Jaude
🇫🇷 Lyon 3ème	Lyon Part-Dieu
🇫🇷 Thiais	Centre Commercial Belle Épine
🇫🇷 Noyelles-Godault	Centre Commercial Aushopping Noyelles
🇫🇷 Vélizy-Villacoublay	Centre Commercial Régional Vélizy 2
🇩🇪 Aachen	Aachen University Building 1380
🇩🇪 Munich	Hauptbahnhof
🇩🇪 Munich	Karlsplatz (Stachus)
🇩🇪 Munich	Marienplatz
🇩🇪 Berlin	Berlin Central Station
🇯🇵 Tokyo	Ueno Station
🇵🇦 Panamá City	Multicentro Mall
🇵🇭 Baguio City	Abanao Square
🇵🇱 Poznań	Politechnika Poznańska Centrum Wykładowe
🇷🇺 Moscow	Okhotny Ryad (Охотный ряд) Mall
🇪🇸 Pamplona	Public University of Navarre (UPNA) Lecture Building
🇬🇧 Sheffield	Meadowhall
🇺🇸 Los Angeles	Union Station
🇺🇸 Denver	Denver Union Station
🇺🇸 Northglenn, Colorado	Northglenn High School
🇺🇸 New York City	Grand Central Terminal
🇲🇾 Kota Kinabalu	Center Point Sabah (Under Construction, Dec 25 2022)

Quality Assurance

• Some Osmose checks (list, map, stats) are available.