During the 2010 General Assembly session, Virginia's legislators passed a law providing additional protections for home improvements.

Let's say you decide to build a front porch on your home. You hire a contractor, get all of the required permits from your local government, and complete the construction in compliance with all applicable rules. But a year later, your local government changes the rules and declares your porch to be illegal because it doesn't comply with the new rules. 

Effective July 1, 2010, your local government can’t declare your home improvements to be illegal as long as you followed the rules in effect at the time the improvements were constructed, even if it has adopted stricter rules in the meantime. You also now have the right to replace an existing wastewater disposal system for an existing building even if a new system wouldn’t otherwise be permitted in that location. However, if your system fails and access to the municipal sewer is available, you’ll be required to connect to it.