140 New Montgomery St
140 New Montgomery St is a 26-story building in Downtown San Francisco with 100% of its floor area within daylight reach of a facade. This screen estimates 368 homes and scores it 100 out of 100 for office-to-residential conversion suitability.
CA-11 · Screened 2026-10-12 · Strong candidate
Where 140 New Montgomery St is
Its block in Downtown San Francisco, drawn from San Francisco's own building outlines and street centerlines.
- Already housing
- Not screened
- 140 New Montgomery St
This building does not pencil on its own, but a modeled RESIDE Act grant would close the gap if the building qualified for one.
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 140 New Montgomery St, 2026-10-12.
| Suitability scoreStrong candidate | 100 / 100 |
|---|---|
| Storiesfrom 377 ft LiDAR (2010) height ÷ 12 ft floor-to-floor | 26 |
| Floor plateper floor, from the city footprint | 13,805 sq ft |
| Daylight efficiencyshare within 35 ft of a facade | 100% |
| Deepest interior pointviability threshold is 80 ft | 28 ft |
| Windowless coreper floor — renovated but never rentable | 0 sq ft |
| Estimated homesat 750 sq ft average | 368 |
| Conversion cost$405/sq ft all-in on 345,131 sq ft | $139.8M |
| Gap before grantshortfall against completed value | $5.1M |
| Modeled RESIDE grantat the statutory per-award cap | $10.0M |
| BuiltSan Francisco's own record of the construction year | 1925 |
| ZoningFinancial District/South Beach | C-3-O(SD) |
| Opportunity Zonenot in a 2018 designated tract | No |
The plan: window line, shape and floor rhythm
48 ft of exterior wall for each home the screen estimates — enough for two- and three-bedroom homes across the plan.
The typical floor has 714 ft of exterior wall, and across 25 residential floors the building carries 17,841 ft of it in total, divided among the 368 homes this screen estimates.
Its plate is elongated at 0.34: a slab or an L, which is why so much of the floor lies within reach of a window: the outline buys daylight that a square plan of the same area would not. How window line and plate shape are measured.
At the model’s 750 sq ft average, the plan works out at about 14.7 homes per floor, repeated on every residential floor, since this building's outline does not change as it rises.
Why 140 New Montgomery St scores 100 out of 100
Daylight efficiency 100, Interior depth 100, Scale 100, Finance 100 — each out of 100, then weighted.
Score components for 140 New Montgomery 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 28 ft from a facade, scored from 80 ft down to 40 ft | 100 | 25% | 25.0 |
| Scale368 estimated homes, scored from 0 up to 150 | 100 | 15% | 15.0 |
| Financecompleted value covers conversion cost with 4% to spare, which tops out the component | 100 | 15% | 15.0 |
Every component scores at or near full marks, so nothing in the geometry or the pro-forma is holding this one back — daylight efficiency carries the most weight of the four.
Built in 1925
San Francisco records this building as going up in 1925, 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 100% daylight figure above deserves.
What the conversion would cost
$405 per square foot all-in across 345,131 sq ft of converted floor, or $139.8M in total — about $380K for each of the 368 homes.
All-in cost per square foot for 140 New Montgomery 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 circulation and service area that earns nothing directly. Against it the model sets a completed value of $366K a home, which for 368 homes is $134.7M.
What would have to be true
A $5.1M gap before any grant, which the modeled $10.0M closes. What would reopen it soonest: circulation efficiency 4% down.
The shortfall before any grant is $5.1M. Closing it from the value side means each of the 368 homes finishing at $380K rather than the $366K the model assumes — 4% more. Closing it from the cost side means getting all-in cost down from $405 to $390 per square foot.
A modeled RESIDE grant of $10.0M moves that threshold to $353K a home. That is below the assumed value, which is why this building counts as unlocked by the grant — subject to it qualifying under the law's vacant-and-abandoned test, which this data cannot show.
Each of these, moved on its own, would be enough to undo that for 140 New Montgomery St:
Single-assumption flip points for 140 New Montgomery St, each holding the other three at their defaults.
| Circulation efficiencythe binding constraint — the least this building would need | 4% downto 77% |
|---|---|
| Completed value per home | 4% downto $353K |
| Average unit size | 4% upto 778 sq ft |
| Conversion cost per square foot | 5% upto $274/sq ft |
All four are sliders in the survey, where 140 New Montgomery St re-scores against your own numbers.
How it compares in Downtown San Francisco
140 New Montgomery St ranks 1st of the 205 buildings screened here, against a median score of 87.
Its floor plate is better lit than 100% of them, and shallower than 90% of them at its deepest interior point. On size it is the 39th 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
1st of 165 in Financial District/South Beach, 1st 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. 140 New Montgomery St ranks 1st of them against a median score of 88, the top score in the group. 121 score 70 or more, their median deepest interior point is 47 ft from a facade against this building’s 28 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). 140 New Montgomery St ranks 1st of them against a median score of 72, the top score in the group. 37 score 70 or more, their median deepest interior point is 59 ft from a facade against this building’s 28 ft, and together they would hold an estimated 18,546 homes.
Its nearest match in size: 603 Commercial St
The screened building closest to 140 New Montgomery St in converted floor area is 603 Commercial St: 349,966 sq ft over 24 stories, against 345,131 sq ft over 26 here.
140 New Montgomery St scores 100 to its 77, and with the size held roughly equal most of that lead comes from interior depth: 100 out of 100 here, 52 there (deepest interior point 59 ft from a facade, scored from 80 ft down to 40 ft). On the money they part ways: 603 Commercial St falls short even with the modeled grant, while 140 New Montgomery St pencils only with the modeled RESIDE grant. The two stand about 2,800 ft apart.
Would it qualify for a RESIDE Act grant?
The model awards 140 New Montgomery 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 140 New Montgomery St
The 4 closest the screen also covers, from 160 ft away. They are the colored outlines on the plan at the top of this page.
- 137 New Montgomery St6 stories · 94% daylit · 64 estimated homes · scores 91/100 (Strong candidate)about 160 ft away
- 138 Minna St9 stories · 99% daylit · 133 estimated homes · scores 98/100 (Strong candidate)about 180 ft away
- 170 New Montgomery St8 stories · 74% daylit · 119 estimated homes · scores 62/100 (Worth a feasibility study)about 210 ft away
- 647 Mission St5 stories · 100% daylit · 26 estimated homes · scores 88/100 (Strong candidate)about 210 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.