Building and roof materials

Hi all,

there had been a small discussion and some questions regarding 3D tagging on the german mailing list recently. For the ease of editing I suggested to use the great 3D preset by Kendzi (which is included in current JOSM version, you just have to activate it). However, there’s no (sufficient) list of building:material and roof:material values, yet. After talking with Kendzi we agreed that we should start a discussion and ask for other’s opinions.

First of all: I love the combo box for roof:shape and the little images so that one knows what the words mean. That’s why we should have something similar for materials, too. However, how should this be done? Should we use a image or a drawing?

When using a drawing it might be difficult to actually understand the exact meaning associated with it: Brick, granite, sandstone,… Yet, using images might lead to confusions: The image shows a special type of roof tile (e.g. a round one) but in reality it’s another subtype (e.g. a rectangular one). However, I’d still prefer the images (e.g. using some of those from the texture page) as they’re more meaningful.

The second and more important question is the list of values itself. On the one hand it should cover most houses out there, on the other hand it should be a compact list with just a few possible values.

That’s why I’m asking for suggestions for building and roof materials and for the level of details we should use for those lists.

In the end I’ll update the wiki accordingly, but wanted to hear some opinions first.

I think that the presentation is the least important now. Images in combo have size 64x64 and they are simply too small to put understandable images there. The problem with icons is that someone have to do them…

That is wrong with value roof_tiles for roof:material except that I forgot space in it?

‘roof_tiles’ is ok for me. I’d just like more alternatives for (roof) materials.

The most common roofs I’ve seen during tagging are:

glass (at least for building parts)

For buildings:


Seems like a good start! The Building attributes page additionally has slate, stone and tar_paper. We might want to adopt these.

I added current values to preset. Can you add some description on wiki?

I propose values for roofs:
reed_roof – for historical building’s [1]
eternit – forbidden but still in use [2]

timber_framing – for historical building’s [3], [4]

[1] -
[2] -
[3] -
[4] -

Thanks! I’ll look into adding the material values to OSM2World.

If I’m not mistaken, this is commonly called thatch in English.


I just updated the wiki pages for building:material and roof:material yesterday.
I really did miss thatch (Schilf in german) on that list, good idea.
Kendzi will add metal to the presets already.

I will add some photos to the roof:material wiki page.

BUT there is some more discussion with building:material today in german mailing list.
More or less: what is building:material used for? really the material of the building, the inner structure?
Or do we use it to describe the facade?
What about a facade:material tag and facade:type tag instead. And building:material for the inner core of the building (it is built of wood or concrete, mostly not made of glass).
Also building:cladding does exist.

I guess we should make it a bit more clear which tags we use to describe a feature.
And I do suggest: building:material for inner core and building:facade for the facade. What is your opinion?


Facade can be only the description of outer, visible surface. Everything is possible behind for example wood.
On the other hand - at the moment there is on need to describe real physical material of wall construction, because often the inner structure it unknown. ( search for words: Mehrschichtige Wand in German).

Your suggestion: building:material for inner core and building:facade for the facade is logical. I suggest such use of both tags too, but instead of building:material make the difference:
building_wall:material, building_terrace:material, building_roof:material - means still - the outer surface material.

Thanks for creating these. I’ve added the standard Key: templates to both of them.

I interpret it as described on Simple 3D Buildings: The “outer material for the building façade”.

Theoretically, we could use a more fine-grained distinction that would allow different “layers” of material. But in practice, the outer layer of material is the only information easily available to mappers, and it’s the only information that is actually used by applications.

From my point of view, it’s the same reason why we use building:levels for levels above the ground, rather than all levels including underground levels: The information which is most commonly tagged by mappers and used by applications gets the “simplest” key.


Thank you for adding them.

And yeah, I do know the definiton in Simple 3D Building, which was set on hte 2nd meeting in Garching.
And I do understand the way people (mappers) do see teh building and which of that seen could be entered easily.
But the rule “simplies tag get the name” is new to me. Maybe not yet seen anywhere.

My point is just: IF the mappers to decide to map both features (building material inner core AND facade), we should make it clear now, which is which tag.
And from the “talking names” point of view, I would set building:material into the section of “it describes the material of the building” - which is mostly inner core, also facade, but not only facade.
Yes, mappers cannot look into the building.

So I would like to change the simple 3d tagging schema in that point into the way of:
building:material - the material of which the whole building is made off (mostly brick, concrete or wood)
and a new Tag
facade:material - which describes the facade explicit.
IMHO it is still simple enough for ammpers to enter the facade:material tag.

Also I would like the 3D programs to use the facade:material tag for outer building.

In a more experienced tagging scheme there would be a facade:* tag for each outside wall :wink:

If we keep building:material for the visible facade type, later on we need to find a good tag name for the inner core material (or change too much already existant tags).

Thank you for your time.


I do not like this suggestion for several reasons.

  1. The current tags are structured in a somewhat consistent manner:
(building|roof) : (material|colour|levels)

This consistency will no longer exist if we swap in “facade” for “building”.

  1. While you have a point that “material” doesn’t indicate that it refers only to the surface, a similar situation exists with roof materials (e.g. tiled roofs will often have a wooden construction underneath). However the “facade” solution only works with building:material, not with roof:material.

  2. A single value might not even be enough to describe the inner construction of a building. A building often has many “layers” - such as plaster on brick walls with a layer of isolation and a wooden frame. So even if we changed the meaning of the building:material tag, it wouldn’t be enough to describe how a building is made up beneath the surface.

  3. Building attributes for 3D are already very chaotic, with many (almost) synonymous keys and values being documented and used. With bots for standardising tagging schemes being de facto banned, it will take a lot of time until everyone has heard of such a change and existing data is re-tagged. And as you can see, only few developers participate in this discussion, so the change would likely only be implemented by some applications. As a result, we would end up with even more tagging fragmentation.


Thank you for the reply. Yeah, it is a small group in here.

About your topics:
Point 1: I do see it as: (building|facade|roof) : (material|colour|levels)
As a extension with one tag more. NOT as a replacement, substitute. Just building:colour would be strange and moslty left out IMHO.

Point 2 and Point 3: I think we are still in the “simple 3D building scheme”. You are right, even facades are mostly a combination. But thats for “future use” and imho not so well suited inside of OSM. Keep it simple with the visible material as facade:material.
Same with roof, you are right, mostly layered with not-visible wooden frame. But thats not visible.

To bad I did not have the time for a more detailed information, but I would see the facade tag only for the area of building:levels, NOT for the roof. The roof is seperated.

E.g. if a building has a concrete inner core, 1 sublevel, 10 level and 2 roof levels, currently we would tag: building:material=plaster for the 10 levels and roof:material=metal for the 2 roof levels.
In my suggestion it would be: building:material=concrete, facade:material=plaster and roof:material=metal.
For the frame below the roof skin, something like roof:frame=wood could be used. IF really needed. IMHO the 4D tagging scheme had some ideas about that already.

Point 4: We are a small subsection of OSM and it is indeed a bit chaotic, thats why the easy 3d building tagging scheme was introduced and adverted, thats why I try to help and point people to it.
As the tag numbers do show, very very few buildings are already tagged in 3D, we are still at the start of it. A fragmentation would happen, but thats not a real problem.
If a building is tagged WITH facade:material AND building:material, the facade material is rendered. If only building:material is tagged, only that material is rendered (as if the facade does not exist, e.g. wooden cabin).
This way it does work with both tagging scheme, and with the change made public by the three main 3d-renderer, it would be used by the new tagging folks, which are not really much.

Thats why we need these central, core, easy 3D tags noted everywhere in the WIKI, for folks to know which are used and rendered and useful at all.
And I do see building:material as a (rather small, indeed) problem. Sure, it works out, but problems with facade tagging will follow.

I do try to get a nice, working subset of 3D tags together and published, like kendzi already has done with presets in JOSM, nice work!.

Thank you for your time


I do not see the point in that. If “building” opposes to “facade”, why doesn’t “roof” oppose to it, too? I’d definitly keep (building|roof) for the front part of the key.
If anything, “facade” should be after the colon. However, I don’t like that either as I’d like to keep the current meaning of the tags (“building:material” is already in use after all) and not change it for the sake of some highly theoretical future tagging uses.

Imho we should find another word for the core (which doesn’t consist of a single material for most buildings, anyway) that a building is built of: Not now, but if it’s needed some time in the future.

I would rather prefer to not have yet another set of tags for 3D tagging. The current tags work and it was hard enough to get all developers working on 3D to agree on the current set of tags. However, what we need (at least that’s why I started this thread) is a list of materials for (roof|building):material (I keep calling it that way :)) to improve the list in kendzi’s great preset.

Anyway, I totally agree with Tordanik and his good points he made, but felt the need to oppose again to an introduction of the facade tag :slight_smile:


I do not want to create a new subset for 3D tagging, just want to make a small subset we all agree to, together for JOSM to be distributed and used by all.
Because of the wild chaos here in forum, wiki and josm - get rid of old, unused tags and write together the subset which should be used.

But looks like the facade tag is not really wanted and agreed to, so I let it rest and use building:material for the subset.
In the wiki I already added example pictures to the building:roof and building:material tags.


Looks quite good already! I’ve also added a “thatch” example from Wikimedia Commons.

One small detail: The table includes “slates”. But previous documentation pages (and taginfo values) use “slate”. I’m not perfectly sure which of these is the more natural form for native speakers, but would have gone with the previously used singular.


You are right, those are called “slate”.