75 Hawthorne St
75 Hawthorne St is a 20-story building in Downtown San Francisco with 72% of its floor area within daylight reach of a facade. This screen estimates 330 homes and scores it 61 out of 100 for office-to-residential conversion suitability.
CA-11 · Screened 2026-10-12 · Worth a feasibility study
No address point in San Francisco’s records falls inside this footprint, so it is named by the closest one that no other screened building claims — usually a site entrance, but check the outline on the plan below before relying on the street number.
Where 75 Hawthorne St is
Its block in Downtown San Francisco, drawn from San Francisco's own building outlines and street centerlines.
- Already housing
- Not screened
- 75 Hawthorne St
This building does not pencil at default assumptions, even with a modeled RESIDE Act grant.
Every floor carries 6,340 sq ft of windowless core — area that must be gutted, seismically braced and sprinklered but can never be rented as an apartment. Across 19 residential floors that is 120,469 sq ft of cost carrying no revenue.
Modeled conversion metrics for 75 Hawthorne St, 2026-10-12.
| Suitability scoreWorth a feasibility study | 61 / 100 |
|---|---|
| Storiesfrom 260 ft LiDAR (2010) height ÷ 12 ft floor-to-floor | 20 |
| Floor plateper floor, from the city footprint | 22,668 sq ft |
| Daylight efficiencyshare within 35 ft of a facade | 72% |
| Deepest interior pointviability threshold is 80 ft | 66 ft |
| Windowless coreper floor — renovated but never rentable | 6,340 sq ft |
| Estimated homesat 750 sq ft average | 330 |
| Conversion cost$405/sq ft all-in on 430,701 sq ft | $174.4M |
| Gap before grantshortfall against completed value | $53.7M |
| Modeled RESIDE grantat the statutory per-award cap | $10.0M |
| BuiltSan Francisco's own record of the construction year | 1987 |
| ZoningFinancial District/South Beach | C-3-O(SD) |
| Opportunity Zonenot in a 2018 designated tract | No |
The plan: window line, shape and floor rhythm
35 ft of exterior wall for each home the screen estimates — enough for two- and three-bedroom homes across the plan.
The typical floor has 608 ft of exterior wall, and across 19 residential floors the building carries 11,557 ft of it in total, divided among the 330 homes this screen estimates.
Its plate is compact at 0.77: 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 17.4 homes per floor, repeated on every residential floor, since this building's outline does not change as it rises.
Why 75 Hawthorne St scores 61 out of 100
Daylight efficiency 64, Interior depth 34, Scale 100, Finance 58 — each out of 100, then weighted.
Score components for 75 Hawthorne St. Points are the subscore times its weight.
| Component | Subscore | Weight | Points |
|---|---|---|---|
| Daylight efficiency72% of the floor area within 35 ft of a facade, scored from 40% up to 90% | 64 | 45% | 28.8 |
| Interior depthdeepest interior point 66 ft from a facade, scored from 80 ft down to 40 ft | 34 | 25% | 8.6 |
| Scale330 estimated homes, scored from 0 up to 150 | 100 | 15% | 15.0 |
| Financeremaining gap is 25% of conversion cost, scored from 60% down to 0% | 58 | 15% | 8.7 |
Most of what it earns comes from daylight efficiency, and what holds it back most is interior depth, at 34 out of 100: deepest interior point 66 ft from a facade, scored from 80 ft down to 40 ft.
Built in 1987
San Francisco records this building as going up in 1987, 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 72% daylight figure above deserves.
What the conversion would cost
$405 per square foot all-in across 430,701 sq ft of converted floor, or $174.4M in total — about $529K for each of the 330 homes.
All-in cost per square foot for 75 Hawthorne St: base cost plus the code work a change of use triggers.
| Base conversion cost | $260/sq ft |
|---|---|
| Seismic retrofit (change of use) | $45/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 | $405/sq ft |
That cost is charged across every converted square foot, including the 120,469 sq ft of windowless core, which has to be gutted, seismically braced and sprinklered like the rest of the building and then earns nothing. Against it the model sets a completed value of $366K a home, which for 330 homes is $120.8M.
What would have to be true
A $53.7M gap before any grant, $43.7M after the modeled one. The smallest single change that would close it: average unit size 26% down.
The shortfall before any grant is $53.7M. Closing it from the value side means each of the 330 homes finishing at $529K rather than the $366K the model assumes — 44% more. Closing it from the cost side means getting all-in cost down from $405 to $280 per square foot.
A modeled RESIDE grant of $10.0M moves that threshold to $498K a home. That is still above the $366K assumed, leaving $43.7M uncovered, which is why the grant does not unlock this one.
Nor do all four levers have to move. For 75 Hawthorne St, one alone would close the gap at:
Single-assumption flip points for 75 Hawthorne St, each holding the other three at their defaults.
| Average unit sizethe binding constraint — the least this building would need | 26% downto 552 sq ft |
|---|---|
| Completed value per home | 36% upto $498K |
| Conversion cost per square foot | 39% downto $159/sq ft |
All four are sliders in the survey, where 75 Hawthorne St re-scores against your own numbers.
How it compares in Downtown San Francisco
75 Hawthorne St ranks 174th of the 205 buildings screened here, against a median score of 87.
Its floor plate is better lit than 14% of them, and shallower than 16% of them at its deepest interior point. On size it is the 47th largest by estimated homes. The full survey of all 205 buildings ranks and maps every one of them, and the list by address links each to its own page.
Within Financial District/South Beach and the C-3-O(SD) zone
143rd of 165 in Financial District/South Beach, 51st of 66 zoned C-3-O(SD) — the comparison that shares its rules, rents and streets.
San Francisco places 165 of the screened buildings in Financial District/South Beach. 75 Hawthorne St ranks 143rd of them against a median score of 88. 121 score 70 or more, their median deepest interior point is 47 ft from a facade against this building’s 66 ft, and together they would hold an estimated 40,456 homes. The group’s top scorer is 870 Market St, at 100.
66 of the screened buildings are zoned C-3-O(SD). 75 Hawthorne St ranks 51st of them against a median score of 72. 37 score 70 or more, their median deepest interior point is 59 ft from a facade against this building’s 66 ft, and together they would hold an estimated 18,546 homes. The group’s top scorer is 140 New Montgomery St, at 100.
Its nearest match in size: 475 Sansome St
The screened building closest to 75 Hawthorne St in converted floor area is 475 Sansome St: 413,692 sq ft over 20 stories, against 430,701 sq ft over 20 here.
75 Hawthorne St scores 61 to its 74, and with the size held roughly equal most of that shortfall comes from interior depth: 34 out of 100 here, 64 there (deepest interior point 54 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 3,500 ft apart.
Would it qualify for a RESIDE Act grant?
The model awards 75 Hawthorne 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 75 Hawthorne St
The 4 closest the screen also covers, from 140 ft away. They are the colored outlines on the plan at the top of this page.
- 55 Hawthorne St11 stories · 89% daylit · 163 estimated homes · scores 94/100 (Strong candidate)about 140 ft away
- 95 Hawthorne St5 stories · 81% daylit · 57 estimated homes · scores 70/100 (Strong candidate)about 160 ft away
- 222 2nd St26 stories · 73% daylit · 425 estimated homes · scores 63/100 (Worth a feasibility study)about 330 ft away
- 680 Folsom St14 stories · 69% daylit · 292 estimated homes · scores 60/100 (Worth a feasibility study)about 350 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.