Yes, they are rewriting, but plenty of language seems to be carried forward, especially in places (like definitions) where it seems no one had raised objections to language established in or before the 1990 code. If you work in design or real estate in Somerville, there are certainly places where the language sounds very familiar.
Zone Smart Somerville seems to have been put together by the same realtor (Neraj Tuli) who is seeking to get rid of the current 4 person limit. The provision had nothing to do (originally) with brothels but much more to do with trying to get rid of SRO and worker's boarding houses, especially in the pro-suburb/anti-urban 1980s.
The way it is supposed to work is precisely by building type. Dwelling units in areas for 'family' housing (single family, two family, triple decker, etc.) are grouped for a particular density and allowed all over the city. SRO or boarding house uses generate a much higher density, and are only allowed in a few particular places. The 4 or fewer definition applies to 'family' housing, the more than 4 definition applies to boarding houses. If you rent to more than 4 people, you are creating a de facto boarding house where one was not permitted.
ps - Cos, you're getting caught up on the difference between a two family house (a building type), a 'family' definition per Section 2.2.53, and a dwelling unit. A "two family house" has two dwelling units, and according to 2.2.53 each of those dwelling units can potentially house a definitional 'family' of up to four unrelated people per unit. That two family house would have to house a total of 9 adults to be over the limit.
Plus or minus four people
Zone Smart Somerville seems to have been put together by the same realtor (Neraj Tuli) who is seeking to get rid of the current 4 person limit. The provision had nothing to do (originally) with brothels but much more to do with trying to get rid of SRO and worker's boarding houses, especially in the pro-suburb/anti-urban 1980s.
The way it is supposed to work is precisely by building type. Dwelling units in areas for 'family' housing (single family, two family, triple decker, etc.) are grouped for a particular density and allowed all over the city. SRO or boarding house uses generate a much higher density, and are only allowed in a few particular places. The 4 or fewer definition applies to 'family' housing, the more than 4 definition applies to boarding houses. If you rent to more than 4 people, you are creating a de facto boarding house where one was not permitted.
ps - Cos, you're getting caught up on the difference between a two family house (a building type), a 'family' definition per Section 2.2.53, and a dwelling unit. A "two family house" has two dwelling units, and according to 2.2.53 each of those dwelling units can potentially house a definitional 'family' of up to four unrelated people per unit. That two family house would have to house a total of 9 adults to be over the limit.