2005 Market St
2005 Market St is a 40-story building in Center City Philadelphia with 61% of its floor area within daylight reach of a facade. This screen estimates 1,337 homes and scores it 34 out of 100 for office-to-residential conversion suitability.
PA-2 & PA-3 · Screened 2026-09-15 · Marginal
Where 2005 Market St is
Its block in Center City Philadelphia, drawn from Philadelphia's own building outlines and street centerlines.
- Already housing
- Not screened
- 2005 Market St
This building does not pencil at default assumptions, even with a modeled RESIDE Act grant.
Every floor carries 20,810 sq ft of windowless core — area that must be gutted, re-plumbed and sprinklered but can never be rented as an apartment. Across 39 residential floors that is 811,578 sq ft of cost carrying no revenue.
Modeled conversion metrics for 2005 Market St, 2026-09-15.
| Suitability scoreMarginal | 34 / 100 |
|---|---|
| Storiesfrom 555 ft LiDAR height ÷ 12 ft floor-to-floor | 40 |
| Floor plateper floor, from the city footprint | 52,953 sq ft |
| Daylight efficiencyshare within 35 ft of a facade | 61% |
| Deepest interior pointviability threshold is 80 ft | 88 ft |
| Windowless coreper floor — renovated but never rentable | 20,810 sq ft |
| Estimated homesat 750 sq ft average | 1,337 |
| Conversion cost$360/sq ft all-in on 2,065,175 sq ft | $743.5M |
| Gap before grantshortfall against completed value | $480.5M |
| Modeled RESIDE grantat the statutory per-award cap | $10.0M |
| BuiltPhiladelphia's own record of the construction year | 1986 |
| ZoningCenter City Philadelphia | CMX5 |
| Opportunity Zonenot in a 2018 designated tract | No |
The plan: window line, shape and floor rhythm
34 ft of exterior wall for each home the screen estimates — enough for two- and three-bedroom homes across the plan.
The typical floor has 1,153 ft of exterior wall, and across 39 residential floors the building carries 44,975 ft of it in total, divided among the 1,337 homes this screen estimates.
Its plate is moderately compact at 0.50: 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 34.3 homes per floor, repeated on every residential floor, since this building's outline does not change as it rises.
Why 2005 Market St scores 34 out of 100
Daylight efficiency 41, Interior depth 0, Scale 100, Finance 0 — each out of 100, then weighted.
Score components for 2005 Market St. Points are the subscore times its weight.
| Component | Subscore | Weight | Points |
|---|---|---|---|
| Daylight efficiency61% of the floor area within 35 ft of a facade, scored from 40% up to 90% | 41 | 45% | 18.6 |
| Interior depthdeepest interior point 88 ft from a facade, scored from 80 ft down to 40 ft | 0 | 25% | 0.0 |
| Scale1337 estimated homes, scored from 0 up to 150 | 100 | 15% | 15.0 |
| Financeremaining gap is 63% of conversion cost, scored from 60% down to 0% | 0 | 15% | 0.0 |
Most of what it earns comes from daylight efficiency, and what holds it back most is interior depth, at 0 out of 100: deepest interior point 88 ft from a facade, scored from 80 ft down to 40 ft.
Built in 1986
Philadelphia records this building as going up in 1986, 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 61% daylight figure above deserves.
What the conversion would cost
$360 per square foot all-in across 2,065,175 sq ft of converted floor, or $743.5M in total — about $556K for each of the 1,337 homes.
All-in cost per square foot for 2005 Market 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 811,578 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 1,337 homes is $263.0M.
What would have to be true
A $480.5M gap before any grant, $470.5M after the modeled one. The smallest single change that would close it: average unit size 64% down.
The shortfall before any grant is $480.5M. Closing it from the value side means each of the 1,337 homes finishing at $556K rather than the $197K the model assumes — 183% more. Closing it from the cost side means getting all-in cost down from $360 to $127 per square foot.
A modeled RESIDE grant of $10.0M moves that threshold to $549K a home. That is still above the $197K assumed, leaving $470.5M uncovered, which is why the grant does not unlock this one.
Nor do all four levers have to move. For 2005 Market St, one alone would close the gap at:
Single-assumption flip points for 2005 Market St, each holding the other three at their defaults.
| Average unit sizethe binding constraint — the least this building would need | 64% downto 269 sq ft |
|---|---|
| Conversion cost per square foot | 88% downto $32/sq ft |
| Completed value per home | 179% upto $549K |
All four are sliders in the survey, where 2005 Market St re-scores against your own numbers.
How it compares in Center City Philadelphia
2005 Market St ranks 89th of the 103 buildings screened here, against a median score of 67.
Its floor plate is better lit than 15% of them, and shallower than 14% of them at its deepest interior point. On size it is the 6th 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
55th of 65 zoned CMX5 — the comparison that shares its rules, rents and streets.
65 of the screened buildings are zoned CMX5. 2005 Market St ranks 55th 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 88 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: 2001 Market St
The screened building closest to 2005 Market St in converted floor area is 2001 Market St: 2,102,097 sq ft over 41 stories, against 2,065,175 sq ft over 40 here.
The two land within a few points of each other — 34 here, 33 there — so at this size the screen reads them as much the same prospect. On the money they sit in the same place: each falls short even with the modeled grant. The two stand about 300 ft apart.
Would it qualify for a RESIDE Act grant?
The model awards 2005 Market 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 2005 Market St
The 4 closest the screen also covers, from 270 ft away. They are the colored outlines on the plan at the top of this page.
- 2001 Market St41 stories · 60% daylit · 1,351 estimated homes · scores 33/100 (Marginal)about 270 ft away
- 2000 Market St29 stories · 66% daylit · 577 estimated homes · scores 42/100 (Marginal)about 450 ft away
- 100 N 20th St5 stories · 74% daylit · 69 estimated homes · scores 48/100 (Marginal)about 720 ft away
- 1900 Market St9 stories · 51% daylit · 299 estimated homes · scores 25/100 (Unlikely)about 730 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.