[pm215]

For this specific case it's a bit less clear because the house has been extended significantly and so the ground floor floor plan is no longer L-shaped, but if you check the floor plan for the first floor (UK terminology) you can see that the rear-facing square-shaped bedroom has a window facing into the garden, making the overall floor plan an L. The shared walls with the neighbours match up about with the second floor floor plan's extreme left and right edges.

The original design on these Victorian terraces is typically an L shape, where the upright of the L had the kitchen in it, and the base of the L is the main block of the house. This allows the room at the back of the main block to have a window facing back into the garden for light. Many have subsequently been extended for extra space and to add bathrooms, which were not originally present. Partially or completely filling in the corner of the L is popular.

[PaulDavisThe1st]

OK, I see what you mean now. It's a very subtle L :)

I am extremely familiar with this shape - my sister lives in one just like this in Walthamstow (prolly not worth 2M yet though).

[michaelt]

It's subtle - but it's an extra 7m of exposed wall on a house that would otherwise only have 10m of exposed wall (the plots being about 5m wide)