448 N 10th St
448 N 10th St is a 7-story building in Center City Philadelphia with 100% of its floor area within daylight reach of a facade. This screen estimates 52 homes and scores it 84 out of 100 for office-to-residential conversion suitability.
PA-2 & PA-3 · Screened 2026-10-04 · Strong candidate
Where 448 N 10th St is
Its block in Center City Philadelphia, drawn from Philadelphia's own building outlines and street centerlines.
- Already housing
- Not screened
- 448 N 10th St
This building does not pencil at default assumptions, even with a modeled RESIDE Act grant.
This footprint has no windowless core at all: every point on the floor plate is within 35 ft of a facade, which is unusual and is the main reason it scores as well as it does.
Modeled conversion metrics for 448 N 10th St, 2026-10-04.
| Suitability scoreStrong candidate | 84 / 100 |
|---|---|
| Storiesfrom 104 ft LiDAR height ÷ 12 ft floor-to-floor | 7 |
| Floor plateper floor, from the city footprint | 8,200 sq ft |
| Daylight efficiencyshare within 35 ft of a facade | 100% |
| Deepest interior pointviability threshold is 80 ft | 25 ft |
| Windowless coreper floor — renovated but never rentable | 0 sq ft |
| Estimated homesat 750 sq ft average | 52 |
| Conversion cost$360/sq ft all-in on 49,201 sq ft | $17.7M |
| Gap before grantshortfall against completed value | $7.5M |
| Modeled RESIDE grantbelow the statutory cap | $3.1M |
| BuiltPhiladelphia's own record of the construction year | 1897 |
| ZoningCenter City Philadelphia | IRMX |
| Opportunity Zonecensus tract 42101037600, 2018 designation | Yes |
The plan: window line, shape and floor rhythm
55 ft of exterior wall for each home the screen estimates — enough for two- and three-bedroom homes across the plan.
The typical floor has 476 ft of exterior wall, and across 6 residential floors the building carries 2,857 ft of it in total, divided among the 52 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 8.7 homes per floor, repeated on every residential floor, since this building's outline does not change as it rises.
Why 448 N 10th St scores 84 out of 100
Daylight efficiency 100, Interior depth 100, Scale 35, Finance 59 — each out of 100, then weighted.
Score components for 448 N 10th St. Points are the subscore times its weight.
| Component | Subscore | Weight | Points |
|---|---|---|---|
| Daylight efficiency100% of the floor area within 35 ft of a facade, scored from 40% up to 90% | 100 | 45% | 45.0 |
| Interior depthdeepest interior point 25 ft from a facade, scored from 80 ft down to 40 ft | 100 | 25% | 25.0 |
| Scale52 estimated homes, scored from 0 up to 150 | 35 | 15% | 5.2 |
| Financeremaining gap is 25% of conversion cost, scored from 60% down to 0% | 59 | 15% | 8.8 |
Most of what it earns comes from daylight efficiency, and what holds it back most is scale, at 35 out of 100: 52 estimated homes, scored from 0 up to 150.
Built in 1897
Philadelphia records this building as going up in 1897, which puts it in the pre-1920 stock.
As a rule, the era that converts most readily: load-bearing masonry, small floor plates laid out before deep-plan offices were possible, operable windows and generous floor-to-floor heights. The usual obstacles are not daylight but hazardous materials, lifts and bringing structure up to current code. 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 49,201 sq ft of converted floor, or $17.7M in total — about $341K for each of the 52 homes.
All-in cost per square foot for 448 N 10th St: base cost plus the code work a change of use triggers.
| Base conversion cost | $260/sq ft |
|---|---|
| Plumbing risers to every unit | $40/sq ft |
| Operable windows and glazing | $30/sq ft |
| Additional egress stair | $18/sq ft |
| Fire sprinklers (NFPA 13R) | $12/sq ft |
| All-in | $360/sq ft |
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 $197K a home, which for 52 homes is $10.2M.
What would have to be true
A $7.5M gap before any grant, $4.4M after the modeled one. The smallest single change that would close it: average unit size 24% down.
The shortfall before any grant is $7.5M. Closing it from the value side means each of the 52 homes finishing at $341K rather than the $197K the model assumes — 73% more. Closing it from the cost side means getting all-in cost down from $360 to $208 per square foot.
A modeled RESIDE grant of $3.1M moves that threshold to $281K a home. That is still above the $197K assumed, leaving $4.4M uncovered, which is why the grant does not unlock this one.
Nor do all four levers have to move. For 448 N 10th St, one alone would close the gap at:
Single-assumption flip points for 448 N 10th St, each holding the other three at their defaults.
| Average unit sizethe binding constraint — the least this building would need | 24% downto 570 sq ft |
|---|---|
| Conversion cost per square foot | 34% downto $171/sq ft |
| Completed value per home | 43% upto $281K |
All four are sliders in the survey, where 448 N 10th St re-scores against your own numbers.
How it compares in Center City Philadelphia
448 N 10th St ranks 19th of the 100 buildings screened here, against a median score of 67.
Its floor plate is better lit than 100% of them, and shallower than 96% of them at its deepest interior point. On size it is the 79th 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.
Its nearest match in size: 2213 Chestnut St
The screened building closest to 448 N 10th St in converted floor area is 2213 Chestnut St: 49,088 sq ft over 5 stories, against 49,201 sq ft over 7 here.
448 N 10th St scores 84 to its 71, and with the size held roughly equal most of that lead comes from interior depth: 100 out of 100 here, 73 there (deepest interior point 51 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 6,900 ft apart.
Would it qualify for a RESIDE Act grant?
The model awards 448 N 10th St $3.1M, 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.
This building does sit in census tract 42101037600, 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 448 N 10th St
The 4 closest the screen also covers, from 370 ft away. They are the colored outlines on the plan at the top of this page.
- 990 Spring Garden St7 stories · 76% daylit · 109 estimated homes · scores 63/100 (Worth a feasibility study)about 370 ft away
- 1025 Callowhill St5 stories · 88% daylit · 50 estimated homes · scores 73/100 (Strong candidate)about 610 ft away
- 319 N 11th St6 stories · 95% daylit · 44 estimated homes · scores 82/100 (Strong candidate)about 920 ft away
- 417 N 8th St5 stories · 85% daylit · 103 estimated homes · scores 72/100 (Strong candidate)about 1,140 ft away
A screen, not a feasibility study, from outlines and heights rather than plans: the method and how to correct a figure. If you know this building’s interior, you know what this model cannot see.