I've always wondered how the growth in the yonge and eglinton area has been guided.
If you look at this image below you'll see that there has been absolutely no development south of Soudan Ave to Millwood Rd (Bordered by Yonge to the west and Mt. Pleasant to the east).
What's the reason for this? Given the fact that growth north of Eglinton as far north as Keewatin Ave has been relatively unrestricted.
There are several reasons:
1. A development application is assessed by the City's planning department. Under the Official Plan, the areas that already have tons of 50's-70's apartment buildings are "Apartment neighbourhoods". This is also why there is no retail in those areas other than along the main commercial streets. That highlighted section is a "stable neighbourhood", and according to the official plan, they should remain as they are. There would also be huge public opposition in the area, HUGE.
2. The developer would have to buy up a couple of rows of houses, which I doubt is very easy. Why would you sell your house if you had one in that area? There are beautiful houses there on tree-lined streets near retail, parks, and the subway. If you own a house there prices are likely to go up or stay up. Many are also renovating the houses or building completely new ones (which are often uglier than the older brick & half-timbred houses, but that's another discussion). Also with the Eglinton LRT coming and all the condo development, the area will likely become even more desirable and attractive.
3. There are several easier areas to develop in that are still available: parking lots and empty areas in the apartment zones.
Examples of areas that can be developed (some already have applications):
Art Shoppe
Parking lots near Millwood & Yonge
The two car service places near Hillsdale & Yonge
Big parking lot at Castlefield & Duplex
In general developers would have an easier time building along Yonge or Eglinton than within the stable low-rise housing areas.
4. Most of those apartment neighbourhoods were built in the 1950's-70's, when there was a different attitude politically, culturally, towards demolishing whole neighbourhoods to build big housing projects. Examples include Regent Park, St. Jamestown, new City Hall.
I find this area similar to High Park in terms of a mix of older low-rise housing and 50's-70's apartment buildings near the subway.