Question about Toronto secondary suites

[JoeUrban]

Hi, first if this is the wrong place to post this please move as needed.

I'm just investigating the Toronto regulations for secondary suites and one item caught my eye:

City of Toronto Zoning By-law 569-2013, as amended (Office Consolidation)

150.10.20.1 General
2) Secondary Suite - Number Permitted in a Detached House, Semi-Detached House or Townhouse
Within a detached house, semi-detached house, or townhouse, each dwelling unit may have a maximum of one secondary suite. [ By-law: 549-2019 ]
(3) Secondary Suite - Number Permitted in a Detached House or a Semi-DetachedHouse in the R Zone
Despite regulation 150.10.20.1(2), in the R zone, each dwelling unit in a detached house or semi-detached house may have more than one secondary suite. [ By-law: 549-2019 ]

So 1 suite per dwelling, but it immediately then allows multiple suites in residential zones, at least in detached or semi-detached.
Is the reasoning for this to only allow limited units in areas where residences are being discouraged in general but homes might have been grandfathered in?, ie non-residential zoning?
Or something completely different?

Thanks!

 

[WislaHD]

I believe the motivation of that exception is to allow a dwelling unit to have both a basement suite and a laneway suite (so two total secondary suites, in addition to the dwelling unit) within the zoning code.

I couldn't say why the regulation is written to provide exception specifically in just the R zone.