Someone decided they wanted to add on a master bedroom and bathroom to the side of their house. Lets just put it where the driveway is and extend the roof over the new part. What could be simpler?
No need to dig a full footing for a new foundation. After all, if the driveway is strong enough to park a car on, it ought to be strong enough to hold a house up. They did put a masonry block wall up on one side, but is wasn't quite high enough to line up with the existing floor. Since it was so close to the ground, they did use pressure treated lumber (someone must have covered that on This Old House once).
However, when it came to the floor framing, they must have missed those episodes, because it was.....well............just too funny for words.
There is nothing really right about the job they did. It's just a waste of material and time.