22 S 17th St

Where 22 S 17th 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 756 ft of exterior wall, and across 19 residential floors the building carries 14,370 ft of it in total, divided among the 437 homes this screen estimates.

Its plate is compact at 0.73: close to a square or a circle, the most efficient envelope an office can have and the least generous one for apartments: little perimeter to divide among homes. How window line and plate shape are measured.

At the model’s 750 sq ft average, the plan works out at about 23.0 homes per floor, repeated on every residential floor, since this building's outline does not change as it rises.

Why 22 S 17th St scores 45 out of 100

Daylight efficiency 50, Interior depth 27, Scale 100, Finance 4 — each out of 100, then weighted.

Most of what it earns comes from daylight efficiency, and what holds it back most is finance, at 4 out of 100: remaining gap is 58% of conversion cost, scored from 60% down to 0%.

Built in 1975

Philadelphia records this building as going up in 1975, which puts it in the late-modern stock.

As a rule, typically the hardest to convert: the deepest plates of any era, large central cores, and floor-to-floor heights tight enough that running residential drainage under a ceiling can be the thing that ends a project. 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 65% daylight figure above deserves.

What the conversion would cost

$360 per square foot all-in across 630,177 sq ft of converted floor, or $226.9M in total — about $519K for each of the 437 homes.

That cost is charged across every converted square foot, including the 220,319 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 437 homes is $86.0M.

What would have to be true

A $140.9M gap before any grant, $130.9M after the modeled one. The smallest single change that would close it: average unit size 60% down.

The shortfall before any grant is $140.9M. Closing it from the value side means each of the 437 homes finishing at $519K rather than the $197K the model assumes — 164% more. Closing it from the cost side means getting all-in cost down from $360 to $136 per square foot.

A modeled RESIDE grant of $10.0M moves that threshold to $496K a home. That is still above the $197K assumed, leaving $130.9M uncovered, which is why the grant does not unlock this one.

Nor do all four levers have to move. For 22 S 17th St, one alone would close the gap at:

All four are sliders in the survey, where 22 S 17th St re-scores against your own numbers.

How it compares in Center City Philadelphia

22 S 17th St ranks 72nd of the 103 buildings screened here, against a median score of 67.

Its floor plate is better lit than 24% of them, and shallower than 33% of them at its deepest interior point. On size it is the 31st 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

43rd of 65 zoned CMX5 — the comparison that shares its rules, rents and streets.

65 of the screened buildings are zoned CMX5. 22 S 17th St ranks 43rd 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 69 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: 1845 Walnut St

The screened building closest to 22 S 17th St in converted floor area is 1845 Walnut St: 659,840 sq ft over 20 stories, against 630,177 sq ft over 20 here.

22 S 17th St scores 45 to its 38, and with the size held roughly equal most of that lead comes from interior depth: 27 out of 100 here, 11 there (deepest interior point 76 ft from a facade, scored from 80 ft down to 40 ft). On the money they sit in the same place: each falls short even with the modeled grant. The two stand about 800 ft apart.

Would it qualify for a RESIDE Act grant?

The model awards 22 S 17th 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 22 S 17th St

The 4 closest the screen also covers, from 200 ft away. They are the colored outlines on the plan at the top of this page.

• 1700 Market St
  32 stories · 58% daylit · 924 estimated homes · scores 31/100 (Marginal)
  about 200 ft away
• 1742 Market St
  14 stories · 100% daylit · 131 estimated homes · scores 92/100 (Strong candidate)
  about 230 ft away
• 1650 Market St
  61 stories · 63% daylit · 1,439 estimated homes · scores 35/100 (Marginal)
  about 410 ft away
• 1818 Market St
  40 stories · 62% daylit · 852 estimated homes · scores 35/100 (Marginal)
  about 490 ft away