917 Chestnut St

Where 917 Chestnut 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

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

The typical floor has 1,054 ft of exterior wall, and across 8 residential floors the building carries 8,435 ft of it in total, divided among the 257 homes this screen estimates.

Its plate is elongated at 0.43: a slab or an L, which is why so much of the floor lies within reach of a window: the outline buys daylight that a square plan of the same area would not. How window line and plate shape are measured.

At the model’s 750 sq ft average, the plan works out at about 32.1 homes per floor, repeated on every residential floor, since this building's outline does not change as it rises.

Why 917 Chestnut St scores 64 out of 100

Daylight efficiency 78, Interior depth 42, 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 1951

Philadelphia records this building as going up in 1951, which puts it in the post-war stock.

As a rule, the period when plates got deep and facades became curtain wall: sealed glazing, lower floor-to-floor heights, and mechanical systems designed around a sealed box. Conversions here usually turn on whether the windows can be made to open and whether ceilings survive new plumbing. 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 79% daylight figure above deserves.

What the conversion would cost

$360 per square foot all-in across 305,904 sq ft of converted floor, or $110.1M in total — about $429K for each of the 257 homes.

That cost is charged across every converted square foot, including the 64,240 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 257 homes is $50.6M.

What would have to be true

A $59.6M gap before any grant, $49.6M after the modeled one. The smallest single change that would close it: average unit size 49% down.

The shortfall before any grant is $59.6M. Closing it from the value side means each of the 257 homes finishing at $429K rather than the $197K the model assumes — 118% more. Closing it from the cost side means getting all-in cost down from $360 to $165 per square foot.

A modeled RESIDE grant of $10.0M moves that threshold to $390K a home. That is still above the $197K assumed, leaving $49.6M uncovered, which is why the grant does not unlock this one.

Nor do all four levers have to move. For 917 Chestnut St, one alone would close the gap at:

All four are sliders in the survey, where 917 Chestnut St re-scores against your own numbers.

How it compares in Center City Philadelphia

917 Chestnut St ranks 53rd of the 103 buildings screened here, against a median score of 67.

Its floor plate is better lit than 49% of them, and shallower than 40% of them at its deepest interior point. On size it is the 45th 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

34th of 65 zoned CMX5 — the comparison that shares its rules, rents and streets.

65 of the screened buildings are zoned CMX5. 917 Chestnut St ranks 34th 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 63 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: 428 Walnut St

The screened building closest to 917 Chestnut St in converted floor area is 428 Walnut St: 269,107 sq ft over 9 stories, against 305,904 sq ft over 9 here.

917 Chestnut St scores 64 to its 58, and with the size held roughly equal most of that lead comes from daylight efficiency: 78 out of 100 here, 68 there (74% 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 2,400 ft apart.

Would it qualify for a RESIDE Act grant?

The model awards 917 Chestnut 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 917 Chestnut St

The 4 closest the screen also covers, from 460 ft away. They are the colored outlines on the plan at the top of this page.

• 819 Chestnut St
  12 stories · 58% daylit · 282 estimated homes · scores 32/100 (Marginal)
  about 460 ft away
• 15 S 11th St
  5 stories · 98% daylit · 27 estimated homes · scores 81/100 (Strong candidate)
  about 530 ft away
• 34 S 11th St
  8 stories · 75% daylit · 159 estimated homes · scores 67/100 (Worth a feasibility study)
  about 720 ft away
• 1101 Market St
  32 stories · 67% daylit · 846 estimated homes · scores 50/100 (Worth a feasibility study)
  about 900 ft away