440 Mission St
440 Mission St is a 5-story building in Downtown San Francisco with 82% of its floor area within daylight reach of a facade. This screen estimates 51 homes and scores it 70 out of 100 for office-to-residential conversion suitability.
CA-11 · Screened 2026-10-12 · Strong candidate
Also addressed as 444 Mission St, 450 Mission St and 456 Mission St: San Francisco’s address records place all 4 on this one footprint.
Where 440 Mission St is
Its block in Downtown San Francisco, drawn from San Francisco's own building outlines and street centerlines.
- Already housing
- Not screened
- 440 Mission St
This building does not pencil at default assumptions, even with a modeled RESIDE Act grant.
Every floor carries 2,626 sq ft of windowless core — area that must be gutted, seismically braced and sprinklered but can never be rented as an apartment. Across 4 residential floors that is 10,502 sq ft of cost carrying no revenue.
Modeled conversion metrics for 440 Mission St, 2026-10-12.
| Suitability scoreStrong candidate | 70 / 100 |
|---|---|
| Storiesfrom 71 ft LiDAR (2010) height ÷ 12 ft floor-to-floor | 5 |
| Floor plateper floor, from the city footprint | 14,792 sq ft |
| Daylight efficiencyshare within 35 ft of a facade | 82% |
| Deepest interior pointviability threshold is 80 ft | 57 ft |
| Windowless coreper floor — renovated but never rentable | 2,626 sq ft |
| Estimated homesat 750 sq ft average | 51 |
| Conversion cost$405/sq ft all-in on 59,169 sq ft | $24.0M |
| Gap before grantshortfall against completed value | $5.3M |
| Modeled RESIDE grantbelow the statutory cap | $3.1M |
| BuiltSan Francisco's own record of the construction year | 1920 |
| ZoningFinancial District/South Beach | C-3-O(SD) |
| Opportunity Zonenot in a 2018 designated tract | No |
The plan: window line, shape and floor rhythm
38 ft of exterior wall for each home the screen estimates — enough for two- and three-bedroom homes across the plan.
The typical floor has 486 ft of exterior wall, and across 4 residential floors the building carries 1,945 ft of it in total, divided among the 51 homes this screen estimates.
Its plate is compact at 0.79: 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 12.8 homes per floor, repeated on every residential floor, since this building's outline does not change as it rises.
Why 440 Mission St scores 70 out of 100
Daylight efficiency 85, Interior depth 58, Scale 34, Finance 84 — each out of 100, then weighted.
Score components for 440 Mission St. Points are the subscore times its weight.
| Component | Subscore | Weight | Points |
|---|---|---|---|
| Daylight efficiency82% of the floor area within 35 ft of a facade, scored from 40% up to 90% | 85 | 45% | 38.0 |
| Interior depthdeepest interior point 57 ft from a facade, scored from 80 ft down to 40 ft | 58 | 25% | 14.6 |
| Scale51 estimated homes, scored from 0 up to 150 | 34 | 15% | 5.1 |
| Financeremaining gap is 9% of conversion cost, scored from 60% down to 0% | 84 | 15% | 12.7 |
Most of what it earns comes from daylight efficiency, and what holds it back most is scale, at 34 out of 100: 51 estimated homes, scored from 0 up to 150.
Built in 1920
San Francisco 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 82% daylight figure above deserves.
What the conversion would cost
$405 per square foot all-in across 59,169 sq ft of converted floor, or $24.0M in total — about $470K for each of the 51 homes.
All-in cost per square foot for 440 Mission 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 10,502 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 51 homes is $18.7M.
What would have to be true
A $5.3M gap before any grant, $2.2M after the modeled one. The smallest single change that would close it: average unit size 9% down.
The shortfall before any grant is $5.3M. Closing it from the value side means each of the 51 homes finishing at $470K rather than the $366K the model assumes — 28% more. Closing it from the cost side means getting all-in cost down from $405 to $315 per square foot.
A modeled RESIDE grant of $3.1M moves that threshold to $410K a home. That is still above the $366K assumed, leaving $2.2M uncovered, which is why the grant does not unlock this one.
Nor do all four levers have to move. For 440 Mission St, one alone would close the gap at:
Single-assumption flip points for 440 Mission St, each holding the other three at their defaults.
| Average unit sizethe binding constraint — the least this building would need | 9% downto 683 sq ft |
|---|---|
| Circulation efficiency | 10% upto 88% |
| Completed value per home | 12% upto $410K |
| Conversion cost per square foot | 15% downto $222/sq ft |
All four are sliders in the survey, where 440 Mission St re-scores against your own numbers.
How it compares in Downtown San Francisco
440 Mission St ranks 147th of the 205 buildings screened here, against a median score of 87.
Its floor plate is better lit than 37% of them, and shallower than 35% of them at its deepest interior point. On size it is the 174th 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
119th of 165 in Financial District/South Beach, 35th 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. 440 Mission St ranks 119th 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 57 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). 440 Mission St ranks 35th 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 57 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: 543 Howard St
The screened building closest to 440 Mission St in converted floor area is 543 Howard St: 56,953 sq ft over 5 stories, against 59,169 sq ft over 5 here.
440 Mission St scores 70 to its 87, and with the size held roughly equal most of that shortfall comes from daylight efficiency: 85 out of 100 here, 100 there (93% of the floor area within 35 ft of a facade, scored from 40% up to 90%). On the money they part ways: 543 Howard St pencils only with the modeled RESIDE grant, while 440 Mission St falls short even with the modeled grant. The two stand about 1,000 ft apart.
Would it qualify for a RESIDE Act grant?
The model awards 440 Mission 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.
It does not sit in a 2018 designated Opportunity Zone, so it would not draw that Section 201 priority.
Other buildings screened near 440 Mission St
The 4 closest the screen also covers, from 150 ft away. They are the colored outlines on the plan at the top of this page.
- 75 1st St42 stories · 73% daylit · 671 estimated homes · scores 64/100 (Worth a feasibility study)about 150 ft away
- 101 1st St63 stories · 59% daylit · 1,457 estimated homes · scores 35/100 (Marginal)about 230 ft away
- 21 1st St23 stories · 83% daylit · 291 estimated homes · scores 81/100 (Strong candidate)about 290 ft away
- 100 1st St27 stories · 73% daylit · 443 estimated homes · scores 60/100 (Worth a feasibility study)about 310 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.