Ireckon - I have refined my gear so much i barely have any anymore. My access weight comprises mostly of single use items such as food water first aid such so on.
An Urban Bug Out Bag Is the same concept as a bug out bag just in a urban setting. Its not carried 24/7 what is carried 24/7 is a get home bag. The difference is, from what I understand and what I follow, Bug out bag is left home and used to "bug out" hence leave town and live off what your bag contains. A Get home bag is a lighter bag for people who are concerned with how long their commutes are who may have to travel by foot or car threw a disaster towards their home. There for the Get home bag is used during long travel towards home with short rest periods including sleeping. A bug out bag is to pick up life and move it in a hurry to a safe spot to live there for a long period of time with the possibility of never being able to return home.
OK, I just call that a bug out bag. When you put "urban" in front of it, it implies somebody who is doing urban stuff, like walking about the city.
In that case, yes, some type of shelter would be in my bug out bag. I live in the suburbs. I think for the bug out bag you describe (at home ready to go), there are certain standard things that should be there for both an urban home and a rural home. However, I still think there are some items that may be different.
Overall, the goal for me is to survival and be rescued, and not to create a home for living long term.