# What's the correct way of adding house numbers to buildings?

I’d like to add addresses in Ramat Gan. I’m a bit confused because there seem to be three different ways of adding house numbers:

1. As a separate node, as in Tel Aviv (apparently the source of this data is the TA municipality)
2. As a vector with interpolation, as on some major streets in Ramat Gan,
3. As a tag on the building itself. This feels like the most correct way, but I don’t see it used a lot. Maybe it’s not used in Israel because corner buildings usually have two addresses?

So what’s the best way to go?

Hello and welcome!

It depend on how much information you have.
If you know only first and last numbers (or even only one and direction) - you’d probably use interpolation.
If you know that some address is in some building - put node somewhere in it.
If you know that the whole building have only one address - add address tags on building polygon
If you know where exactly entrance is positioned - adding node on the building polygon with entrance=yes and address info - will be just perfect.

Thank you. As I didn’t see address tags on building polygons anywhere, I thought there was something wrong with this method.

Besides your 1. and 2., there are two other ways of tagging addresses:
B. Create a node at the middle of the building edge, and add the address property to that node
I’m not sure which you mean in 3.

I think B. is better than A. (and certainly better than 1. and 2.). Certainly B. is best on corner buildings (because there is no other way to do two addresses), also anywhere else that there is ambiguity about the address (for example one building between two streets). And in general, I don’t see any downside to B. However, method A. is used in some places already, and I don’t see it as worth changing.

yrtimiD explained it perfectly:

I would recommend the following option:

Beside that its better than nothing to do that but it is not a final status, just a temporary one:

A final OSM map should show the housenumbers of each and every building.
So starting with the first and last housenumber is a great step forward but needs guessing to define nodes for every building.
Even if you make a mistake with the housenumber nodes, nobody will throw stones on you.
I personally find it very easy with the right tools (OSMAND on Android) to fix those issues in a survey and make sure the entrance and housenumber is defined 100% correctly.

But it is a very big job.

It took me I think a year to add housenumbers by survey for Netanya.

A personal tip. Before you start tagging housenumbers add all buildings via Bing Satimages.
It is a lot easier to add housenumbers if a building is visible on a map.

Great, so I’ll keep adding house numbers.
A follow-up question, if I may:
Is it OK to fix the address nodes taken from the Tel Aviv Municipality? Is it OK to move, change and delete incorrect address nodes in Tel Aviv?

hmm…

I think their is nothing against fixing data.
Just interesting that you found mistakes, in my tests the data is very accurate in terms of position and content.

But I think they do not care so much about sub numbers like 20 aleph or 20 bet etc.

Yes, and also there are a lot of addresses of non-existing buildings, such as in the former Wholesale market.

I’m pretty sure we need to preserve addresses for empty places as once something may appear there. Address is not relevant to actual building but just place mark on the street.

The use of TA municipal data is conditional on our not changing it. See the license - http://www.tel-aviv.gov.il/OnlineServices/DataTLV/Documents/%D7%A8%D7%99%D7%A9%D7%99%D7%95%D7%9F%20%D7%9C%D7%A9%D7%99%D7%9E%D7%95%D7%A9%20%D7%91%D7%9E%D7%99%D7%93%D7%A2%20-%20%D7%A2%D7%99%D7%A8%D7%99%D7%99%D7%AA%20%D7%AA%D7%9C-%D7%90%D7%91%D7%99%D7%91-%D7%99%D7%A4%D7%95.pdf

Eric, thank you for the reference.

So you mean that we are not allowed by license to fix or change the data they provided ?
Is that really fitting the OSM standards?

It is not good. But I think OSM is better with that data as is, than without it.
We could ask them for special permission to make constructive changes. But I think we tried this in the past and they weren’t helpful.
You could maybe argue that each address is an independent piece of data, and if you don’t use (i.e. delete) one piece, you’re not affecting the other pieces. But that argument can be questioned. I’m not sure I want to rely on it.