The porch roof almost never matches the main roof
Most triple-deckers around Fall River were built with a stacked rear porch, and that porch roof is nearly flat where the main roof over the living space is pitched. The two get built and repaired on completely different schedules, so it is common to find a main roof with twenty years of life left sitting above a porch membrane that is already failing at the seams.
We measure and inspect the porch section separately from the main slope every time, because pricing them as one roof either overcharges for the small flat section or, worse, misses that it needs attention now while the main roof does not.
Three units, three sets of vents
Each unit in a triple-decker heats and holds moisture differently depending on who lives there and how the thermostat gets used, and that moisture finds its way into a shared attic space through bath fans, kitchen vents and gaps around light fixtures on the top floor. A ridge vent that is continuous on paper does no good if the soffit intake below it is blocked by decades of paint or a prior owner's insulation job.
We check every soffit bay from inside the attic, not just from the ground, before assuming the ventilation is doing its job.
Old layers stack up faster on a triple-decker
A lot of the triple-deckers in the Flint area and off South Main Street have changed hands more than once since they were built, and each owner tends to add a layer rather than strip the old one. It is common to pull a permit history that shows one re-roof on record and then find two layers of shingle once the tear-off actually starts.
That gets flagged during the inspection, not discovered mid-job, because Massachusetts code caps a roof at two layers and a third means the deck has to be stripped bare regardless of what the original scope assumed.
Access and staging on a tight lot
Triple-deckers usually sit close to the property line and close to the house next door, so there is rarely room for a standard dumpster placement or ladder setup without talking to a neighbor first. Tarps go down over foundation plantings and any parked cars get moved before tear-off starts, and we walk the lot with the homeowner ahead of time to agree on exactly where the debris chute and dumpster will sit for the week.
Overhead wires running to the pole at the street are noted on every triple-decker inspection too, since the service drop often crosses close enough to the roofline that the utility needs a heads up before staging begins.
What goes in the written scope
The scope for a triple-decker spells out the main roof, the porch section, the layer count found once tear-off starts, and any deck repair by the board rather than a flat allowance, so a homeowner comparing quotes from different contractors can see exactly what each price does and does not include.