Building length and width

Hi:) Could you tell me is it possible to create (draw) building with specified width and length? I used key:length and key:width for this problem, but it seems that building does not recognize them because building shape stays the same (ie. when i change values for length and width, building shape stays the same as I drawn it initially).

Yes, it is possible, but you don’t need it actually. You should draw a building from aerial imagery and draw how it is there.

Length and width keys are not for buildings and they won’t change the shape you’ve drawn.

Finish the walkthrough in iD - it’s explained there how to draw buildings.

I can see you’ve drawn many nonexistent buildings. Please use Bing imagery.

I know, but I thought that I have already deleted them, but they are still there… I made them because I was trying to learn how to create building with specified properties. For which width and length are then used? Why is it important to use Bing imagery?

How can I add buildings that are new and not visible on the satellite map if I can’t specify the dimensions of the building?

The online editor iD has a scale that you can use to get the length roughly correct. There are more feature-rich editor programs (such as JOSM) which offer quite precise measuring tools on top of that, which would allow you to draw building outlines with centimetre precision. But those tools have a steeper learning curve and such precision is generally unnecessary. For most use cases of OSM data, it doesn’t make a huge difference if a building is a little too small or too big, so most mappers will be satisfied with having a rough outline in place until one of the available imagery layers is updated to show the building.


The keys key:length and key:width are not used to change the shape of the building you have drawn. They are just used to describe the actual width and length of a feature, in this case a building. Let me tell you that usually nobody specifies these tags when drawing building. Check the wiki page

You don’t have to use precisely Bing imagery, but it is the most used. There are other imageries you can use like Maxar, ESRI. etc. The only requirement is that they don’t have some kind of copyright.


Mostly length=* is used for rivers and width=* is used on roads.

In iD you can press [Ctrl]+[Shift]+[M] to turn on the measurement panel.

Thanks a lot!