Building with multiple house numbers.

I’m new and still learning, not even sure if this or or one of the mail lists is the best place to ask. :slight_smile:

There are a number of duplex houses in an area I am trying to add to OSM where one address is on the ground level and the other address is up an outside flight of stairs. That is the addresses are vertically stacked. The suggestions at don’t seem to fit and even there it is noted that “there is currently no consensus on this”.

  1. Adding separate entrance nodes can result in address nodes on top of one another in this case so that seems to be a poor choice.
  2. Splitting the building in two horizontally (terracing) makes little sense here.
  3. Separating addr:housenumber values with semi-colons (the “standard OSM separator”) sounds good but there appear to be only about 2.5K uses of that according to the tag info site. There are 46K instances of using a comma separator and 40K using a dash separator. But a dash seems like it should also have a addr:interpolation tag to indicate odd/even number and in the cases I’ve seen there could be missing numbers (i.e. addresses skip a possible intermediate).
  4. The proposal at using keys like addr:1:housenumber and addr:2:housenumber seems the cleanest but I only see 8 usages of that at the tag info site so it does not appear to have taken hold.

I am currently leaning toward tagging as follows:


The idea being to use the current common key (addr:housenumber) with a list of numbers separated by the “standard” OSM delimiter and then, in addition, use the method proposed at

Does this make sense?

It seems that the situation with different housenumbers that are vertically stacked is quite seldom, or not?

So not many users have been encountering this situation. You can try to invent a data modet with a differentiation in the addr:housenumber tag and document it in the OSM wiki via a proposal. But I fear that no apps or quality assurance tools will pay attention to it soon.

I think I’d be tempted to place the upper dwelling’s entrance node at the place where its staircase meets ground level, rather than at the location of the dwelling door itself. Only if that location is coincident with the ground floor dwelling door would I use a single node with multiple values for the addr:housenumber tag. Would that be a reasonable compromise?