1 S Broad St

Where 1 S Broad St is

Its block in Center City Philadelphia, drawn from Philadelphia's own building outlines and street centerlines.

The plan: window line, shape and floor rhythm

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

The typical floor has 726 ft of exterior wall, and across 25 residential floors the building carries 18,148 ft of it in total, divided among the 509 homes this screen estimates.

Its plate is moderately compact at 0.53: 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 20.4 homes per floor, repeated on every residential floor, since this building's outline does not change as it rises.

Why 1 S Broad St scores 81 out of 100

Daylight efficiency 92, Interior depth 84, Scale 100, Finance 25 — each out of 100, then weighted.

Most of what it earns comes from daylight efficiency, and what holds it back most is finance, at 25 out of 100: remaining gap is 45% of conversion cost, scored from 60% down to 0%.

Built in 1930

Philadelphia records this building as going up in 1930, 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 86% daylight figure above deserves.

What the conversion would cost

$360 per square foot all-in across 555,934 sq ft of converted floor, or $200.1M in total — about $393K for each of the 509 homes.

That cost is charged across every converted square foot, including the 78,325 sq ft of windowless core, which has to be gutted, re-plumbed and sprinklered like the rest of the building and then earns nothing. Against it the model sets a completed value of $197K a home, which for 509 homes is $100.1M.

What would have to be true

A $100.0M gap before any grant, $90.0M after the modeled one. The smallest single change that would close it: average unit size 47% down.

The shortfall before any grant is $100.0M. Closing it from the value side means each of the 509 homes finishing at $393K rather than the $197K the model assumes — 100% more. Closing it from the cost side means getting all-in cost down from $360 to $180 per square foot.

A modeled RESIDE grant of $10.0M moves that threshold to $374K a home. That is still above the $197K assumed, leaving $90.0M uncovered, which is why the grant does not unlock this one.

Nor do all four levers have to move. For 1 S Broad St, one alone would close the gap at:

All four are sliders in the survey, where 1 S Broad St re-scores against your own numbers.

How it compares in Center City Philadelphia

1 S Broad St ranks 33rd of the 103 buildings screened here, against a median score of 67.

Its floor plate is better lit than 60% of them, and shallower than 66% of them at its deepest interior point. On size it is the 24th largest by estimated homes. The full survey of all 103 buildings ranks and maps every one of them, and the list by address links each to its own page.

Within the CMX5 zone

24th of 65 zoned CMX5 — the comparison that shares its rules, rents and streets.

65 of the screened buildings are zoned CMX5. 1 S Broad St ranks 24th of them against a median score of 67. 28 score 70 or more, their median deepest interior point is 58 ft from a facade against this building’s 46 ft, and together they would hold an estimated 30,650 homes. The group’s top scorer is 112 N Broad St, at 93.

Its nearest match in size: 1500 Walnut St

The screened building closest to 1 S Broad St in converted floor area is 1500 Walnut St: 556,113 sq ft over 22 stories, against 555,934 sq ft over 26 here.

1 S Broad St scores 81 to its 87, and with the size held roughly equal most of that shortfall comes from daylight efficiency: 92 out of 100 here, 100 there (91% of the floor area within 35 ft of a facade, scored from 40% up to 90%). On the money they sit in the same place: each falls short even with the modeled grant. The two stand about 1,100 ft apart.

Would it qualify for a RESIDE Act grant?

The model awards 1 S Broad St $10.0M, 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 1 S Broad St

The 4 closest the screen also covers, from 130 ft away. They are the colored outlines on the plan at the top of this page.

• 1327 Chestnut St
  18 stories · 63% daylit · 386 estimated homes · scores 39/100 (Marginal)
  about 130 ft away
• 1326 Chestnut St
  8 stories · 100% daylit · 76 estimated homes · scores 87/100 (Strong candidate)
  about 340 ft away
• 100 S Broad St
  22 stories · 97% daylit · 610 estimated homes · scores 90/100 (Strong candidate)
  about 340 ft away
• 115 S Broad St
  21 stories · 96% daylit · 180 estimated homes · scores 93/100 (Strong candidate)
  about 360 ft away