Copyright wise you'd need to make sure the map is either aged into public domain (unlikely if new) or you have explicit permission of the copyright holder to put into OSM. JOSM can do this with the [relevant plugin][1], but to do something like this in browser you might need to (ab)use [OsmInEdit][2] or similar alternate editor. iD can use custom imagery URLS, but you will probably need to re-project the map and have them cut up into tile and hosted somewhere. somewhere if you want to go down this route. [1]: https://wiki.openstreetmap.org/wiki/JOSM/Plugins/ImportImagePlugin [2]: https://wiki.openstreetmap.org/wiki/OsmInEdit#Floor_plan_.26_imagery

Copyright wise you'd need to make sure the map is either aged into public domain (unlikely if new) or you have explicit permission of the copyright holder to put into OSM. JOSM can do this with the [relevant plugin][1], but to do something like this in browser you might need to (ab)use [OsmInEdit][2] or similar alternate editor. iD can use custom imagery URLS, you will probably need to re-project the map and have them hosted somewhere. [1]: https://wiki.openstreetmap.org/wiki/JOSM/Plugins/ImportImagePlugin [2]: https://wiki.openstreetmap.org/wiki/OsmInEdit#Floor_plan_.26_imagery