It’s been a workhorse of affordable housing in urban New England for more than a century, and a building type that is as Boston as a Dunkin’ coffee. But in keeping with the city’s predilection for barstool debates, there’s disagreement about what to call it: Is it the triple-decker or the three-decker?
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The triple-decker building boom was a very pragmatic response to a housing crush in this fast-industrializing region. Waves of newcomers, often immigrants from Eastern and Southern Europe, were drawn to the factories and textile mills of New England during the second half of the 19th century. Many had been staying in stables and tents or were crowded in substandard conditions. Business leaders had a need, and private developers bought up parcels and built the supply.
Source: Three Cheers for the Triple-Decker, Boston’s Iconic Cheap Housing – Bloomberg