This is a really nice kitchen extension. In response to an "oppressively" low ceiling height, the architects -- DGN Studio -- lowered the existing ground floor by about 500mm. At the same time, they created a kind of "concrete tray" that fills the width of the Victorian home's property and extends outward to create a sunken patio space off said kitchen. From the outside, this drop makes the house feel as if it's sitting on a concrete plinth -- hence the name. (A good photo of this can be found here.) It's a simple move, but a good one. Sometimes you just have to play with the section. If you can't see the above video, click here.