This is EcoPad, an à-la-Litework starter house.

Credits:

Columns: ATS
Indoor Fence: Tiggy's Modern Sim Objects http://www.m-sim-o.com
Floors: Reflex, Tribecca, MTS2
Walls: Habitations, Simplacement, Tribecca
Stairs: Numenor's recolorable wooden stairs (MTS2)