We transition to SFH incredibly quickly. The city is small and linear, both of which bring post-WWII suburbia within a couple of blocks of the heart of downtown in some directions.
The nearest SFH to the core are probably the in-fill houses that replaced central gardens in the rowhouse blocks:
Block exterior:
Block interior:
*****
In a broader sense, the city is so linear that Empire Avenue (the ring road, or railroad, in 1949. There was almost zero development outside it at that time) is a brick wall between rowhouses and SFH.
And just to clarify, the full extent of the rowhouse districts, basically the core, is Craigmillar to Quidi Vidi:
(This is not the shortest distance between them, but I dragged out the blue line to try to basically encircle the rowhouse areas).