Hey - pretty new to OSM, mapped out as much of my neighborhood as I could yesterday with sat imagery.
There’s a lot of construction going on and the sat imagery is about two years out of date, I know houses exist where there’s just a blank spot. Is it acceptable to just draw an area box where I know there is a house? Do I need to tag that in any special way?
With sidewalks, is it generally accepted as better to map them separately? If so, should a relation be added to a street? The sidewalks generally have the path, then two feet of grass, then the curb, then the street. Would each driveway attached to a sidewalk just be marked as no curb in that area?
You can draw and tag the buildings (and every other object) even if they are not visible on aerial images. You can add a note-tag to inform other mapers that the object is not visible on aerial images yet or you can add source=survey to indicate where you get the information from.
Some sidewalks are mapped just as a tag on the adjacent road and some are mapped separately. Wiki implies that the grass divider is enough that mappers may add it separately. I prefer to map it separately so i don’t have to split roads into many segments just to change sidewalk related tags, intersections with only some corners crossable or requiring a walk pushbutton can be noted more clearly, connections to the road can be detailed such as the tactile bumps, and sidewalks present as one path between two roads can be resembled with less confusion for what to attach it to. I was using sidewalk=separate vs sidewalk=use_sidepath on the road for if there was more than a curb (=kerb in tagging form) dividing them.
I like descriptive comment/source entries to edits. Though source= tags sound good I don’t have interest in trying to describe where the source was for the initial imagery trace, local survey of a surface makeup, logic for streetname pulled in from tiger with the building number from openstreetcam, a phone number from a business receipt, etc. all in one tag (or many subtags). Browsing edit history can help then sort that out form change comments but on bigger edits and of multiple things you cannot tell which sources were for what.