db table column design question
1.1.2 as a location seems very arbitrary.  Your structure will not allow you to do much dynamic reporting and scaling up would cause issues. Every time you need to query up the chain, you will need to break the item up, which will break your index. 

1.1.1 may refer to NY Fl 5, but 1.1.2 could refer to LA (los angeles, Louisiana,???) floor 4.

TBL1 - 1, USA
TBL2 - 100, STATE, TBL1.FK
TBL3 - 1000, CITY, TBL2.FK
TBL4 - 10000, BUILDING, TBL3.FK, May want to also include ZIPCODE here.
TBL5 - 100000, FLOOR, TBL4.FK

In you Data warehouse, you could flatten it, but you might want to keep separate Dimension tables for cube reporting.