117 N 8th St

Where 117 N 8th 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

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

The typical floor has 415 ft of exterior wall, and across 7 residential floors the building carries 2,908 ft of it in total, divided among the 63 homes this screen estimates.

Its plate is moderately compact at 0.65: 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 9.0 homes per floor, repeated on every residential floor, since this building's outline does not change as it rises.

Why 117 N 8th St scores 84 out of 100

Daylight efficiency 100, Interior depth 97, Scale 42, Finance 53 — each out of 100, then weighted.

Most of what it earns comes from daylight efficiency, and what holds it back most is scale, at 42 out of 100: 63 estimated homes, scored from 0 up to 150.

Built in 1920

Philadelphia records this building as going up in 1920, 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 95% daylight figure above deserves.

What the conversion would cost

$360 per square foot all-in across 62,705 sq ft of converted floor, or $22.6M in total — about $358K for each of the 63 homes.

That cost is charged across every converted square foot, including the 3,244 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 63 homes is $12.4M.

What would have to be true

A $10.2M gap before any grant, $6.4M after the modeled one. The smallest single change that would close it: average unit size 28% down.

The shortfall before any grant is $10.2M. Closing it from the value side means each of the 63 homes finishing at $358K rather than the $197K the model assumes — 82% more. Closing it from the cost side means getting all-in cost down from $360 to $198 per square foot.

A modeled RESIDE grant of $3.8M moves that threshold to $298K a home. That is still above the $197K assumed, leaving $6.4M uncovered, which is why the grant does not unlock this one.

Nor do all four levers have to move. For 117 N 8th St, one alone would close the gap at:

All four are sliders in the survey, where 117 N 8th St re-scores against your own numbers.

How it compares in Center City Philadelphia

117 N 8th St ranks 22nd of the 100 buildings screened here, against a median score of 67.

Its floor plate is better lit than 71% of them, and shallower than 72% of them at its deepest interior point. On size it is the 75th largest by estimated homes. The full survey of all 100 buildings ranks and maps every one of them, and the list by address links each to its own page.

Within the CMX4 zone

2nd of 15 zoned CMX4 — the comparison that shares its rules, rents and streets.

15 of the screened buildings are zoned CMX4. 117 N 8th St ranks 2nd of them against a median score of 58. 5 score 70 or more, their median deepest interior point is 64 ft from a facade against this building’s 41 ft, and together they would hold an estimated 4,016 homes. The group’s top scorer is 901 Arch St, at 84.

Its nearest match in size: 441 N 5th St

The screened building closest to 117 N 8th St in converted floor area is 441 N 5th St: 61,411 sq ft over 4 stories, against 62,705 sq ft over 8 here.

117 N 8th St scores 84 to its 46, and with the size held roughly equal most of that lead comes from interior depth: 97 out of 100 here, 28 there (deepest interior point 69 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 2,600 ft apart.

Would it qualify for a RESIDE Act grant?

The model awards 117 N 8th St $3.8M, 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.

This building does sit in census tract 42101000200, a 2018 designated Opportunity Zone, which Section 201 lets HUD favor — one of the few statutory priorities this screen can actually check.

Other buildings screened near 117 N 8th St

The 4 closest the screen also covers, from 190 ft away. They are the colored outlines on the plan at the top of this page.

• 801 Arch St
  6 stories · 71% daylit · 133 estimated homes · scores 56/100 (Worth a feasibility study)
  about 190 ft away
• 736 Arch St
  7 stories · 97% daylit · 129 estimated homes · scores 91/100 (Strong candidate)
  about 420 ft away
• 901 Arch St
  7 stories · 100% daylit · 47 estimated homes · scores 84/100 (Strong candidate)
  about 580 ft away
• 150 N Independence Mall W
  8 stories · 52% daylit · 407 estimated homes · scores 25/100 (Unlikely)
  about 600 ft away