417-435 Washington St

Where 417-435 Washington St is

Its block in Downtown Boston, drawn from Boston's own building outlines and street centerlines.

The plan: window line, shape and floor rhythm

39 ft of exterior wall for each home the screen estimates — enough for two- and three-bedroom homes across the plan.

The typical floor has 665 ft of exterior wall, and across 9 residential floors the building carries 5,988 ft of it in total, divided among the 152 homes this screen estimates.

Its plate is moderately compact at 0.45: a squarish plan, with enough perimeter for a conventional double-loaded corridor. How window line and plate shape are measured.

At the model’s 750 sq ft average, the plan works out at about 16.9 homes per floor, repeated on every residential floor, since this building's outline does not change as it rises.

Why 417-435 Washington St scores 100 out of 100

Daylight efficiency 100, Interior depth 100, Scale 100, Finance 100 — each out of 100, then weighted.

Every component scores at or near full marks, so nothing in the geometry or the pro-forma is holding this one back — daylight efficiency carries the most weight of the four.

Built in 1925

Boston records this building as going up in 1925, which puts it in the interwar stock.

As a rule, steel or concrete frames with punched windows and plates still narrow enough for daylight to reach the middle, often with high ceilings. Among the most convertible stock there is, and the reason so many early conversions were of buildings this age. That is the era’s general tendency rather than a finding about this building — the model reads an outline and a height, and can see nothing inside — but it is the first thing an architect would want to know, and it colours how much confidence the 100% daylight figure above deserves.

What the conversion would cost

$360 per square foot all-in across 143,146 sq ft of converted floor, or $51.5M in total — about $339K for each of the 152 homes.

That cost is charged across every converted square foot, including the circulation and service area that earns nothing directly. Against it the model sets a completed value of $442K a home, which for 152 homes is $67.1M.

What would have to be true

This one already clears the bar. The question is how much room it has before it stops.

At $442K a home, completed value covers the $51.5M of work with $15.6M to spare. Value per home would have to fall to $339K — 23% below the assumption — before the conversion stopped penciling, or all-in cost would have to rise from $360 to $469 per square foot. Neither is a wide margin in a market that moves, but this building does not need a grant to work.

Each of these, moved on its own, would be enough to undo that for 417-435 Washington St:

All four are sliders in the survey, where 417-435 Washington St re-scores against your own numbers.

How it compares in Downtown Boston

417-435 Washington St ranks 1st of the 96 buildings screened here, against a median score of 89.

Its floor plate is better lit than 81% of them, and shallower than 79% of them at its deepest interior point. On size it is the 53rd largest by estimated homes. The full survey of all 96 buildings ranks and maps every one of them, and the list by address links each to its own page.

Within the SKY-LOW-DT zone

1st of 25 zoned SKY-LOW-DT — the comparison that shares its rules, rents and streets.

25 of the screened buildings are zoned SKY-LOW-DT. 417-435 Washington St ranks 1st of them against a median score of 91, the top score in the group. 24 score 70 or more, their median deepest interior point is 35 ft from a facade against this building’s 35 ft, and together they would hold an estimated 2,629 homes. The group’s top scorer is 36-44 Broad St, at 100.

Its nearest match in size: 10-30 School St

The screened building closest to 417-435 Washington St in converted floor area is 10-30 School St: 131,377 sq ft over 9 stories, against 143,146 sq ft over 10 here.

417-435 Washington St scores 100 to its 81, and with the size held roughly equal most of that lead comes from interior depth: 100 out of 100 here, 53 there (deepest interior point 59 ft from a facade, scored from 80 ft down to 40 ft). On the money they sit in the same place: each pencils without a subsidy. The two stand about 700 ft apart.

Would it qualify for a RESIDE Act grant?

The model awards 417-435 Washington St $9.1M, on the assumption it qualifies. Whether it does, no published dataset can say.

That figure assumes the building meets the Act’s vacant-and-abandoned test, which turns on code-enforcement and receivership records no city publishes.

It does not sit in a 2018 designated Opportunity Zone, so it would not draw that Section 201 priority.

Other buildings screened near 417-435 Washington St

The 4 closest the screen also covers, from 180 ft away. They are the colored outlines on the plan at the top of this page.

• 17-33 Winter St
  7 stories · 83% daylit · 82 estimated homes · scores 78/100 (Strong candidate)
  about 180 ft away
• 28-38 Winter St
  14 stories · 95% daylit · 106 estimated homes · scores 95/100 (Strong candidate)
  about 260 ft away
• 32-38 Bromfield St
  6 stories · 100% daylit · 44 estimated homes · scores 89/100 (Strong candidate)
  about 290 ft away
• 60-70 Temple Pl
  7 stories · 95% daylit · 50 estimated homes · scores 89/100 (Strong candidate)
  about 320 ft away