350 Post St

350 Post St is a 11-story building in Downtown San Francisco with 100% of its floor area within daylight reach of a facade. This screen estimates 95 homes and scores it 95 out of 100 for office-to-residential conversion suitability.

CA-11 · Screened 2026-10-12 · Strong candidate

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Also addressed as 360 Post St: San Francisco’s address records place both on this one footprint.

Where 350 Post St is

Its block in Downtown San Francisco, drawn from San Francisco's own building outlines and street centerlines.

Suitability score

0–29

30–49

50–69

70–100

Already housing
Not screened
350 Post St

350 Post St and the 1,000 ft of Downtown San Francisco around it. The streets are drawn at the width of the right-of-way they run down, sidewalks included, and named, and every building on these blocks is drawn. What is left open and stippled is neither: a surface lot, a plaza or a vacant parcel. The screened buildings are colored by the ramp above, the same one the district map uses, carry their score, and each is a link to its own page. Each casts a shadow as long as its measured height lets it, so towers stand out from the low buildings around them; the unscreened buildings have no measured height and cast none. 350 Post St is outlined in its own score color at the outline it covers at ground level. The inset places it among every building the screen covers.

Floor plan: 100% of each floor sits within daylight reach of a facade, with no dead core at all. The shading is daylight, darkest at the windows and gone 35 ft in. The dimension marks the deepest interior point, 32 ft from the nearest window. A–A is where the section beside it is cut.

Section A–A: cut across the depth of the plate, through the middle of the core. Daylight reaches 35 ft in from every facade, and here it meets in the middle: the plate is thin enough that no floor is left windowless. The shaded ground floor is converted like the rest and counted as no homes.

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 350 Post St, 2026-10-12.

Suitability scoreStrong candidate	95 / 100
Storiesfrom 139 ft LiDAR (2010) height ÷ 12 ft floor-to-floor	11
Floor plateper floor, from the city footprint	8,954 sq ft
Daylight efficiencyshare within 35 ft of a facade	100%
Deepest interior pointviability threshold is 80 ft	32 ft
Windowless coreper floor — renovated but never rentable	0 sq ft
Estimated homesat 750 sq ft average	95
Conversion cost$405/sq ft all-in on 89,536 sq ft	$36.3M
Gap before grantshortfall against completed value	$1.5M
Modeled RESIDE grantbelow the statutory cap	$5.7M
BuiltSan Francisco's own record of the construction year	1972
ZoningFinancial District/South Beach	C-3-R
Opportunity Zonenot in a 2018 designated tract	No

The plan: window line, shape and floor rhythm

49 ft of exterior wall for each home the screen estimates — enough for two- and three-bedroom homes across the plan.

The typical floor has 467 ft of exterior wall, and across 10 residential floors the building carries 4,669 ft of it in total, divided among the 95 homes this screen estimates.

Its plate is moderately compact at 0.52: 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 9.5 homes per floor, repeated on every residential floor, since this building's outline does not change as it rises.

Why 350 Post St scores 95 out of 100

Daylight efficiency 100, Interior depth 100, Scale 63, Finance 100 — each out of 100, then weighted.

Score components for 350 Post 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 32 ft from a facade, scored from 80 ft down to 40 ft	100	25%	25.0
Scale95 estimated homes, scored from 0 up to 150	63	15%	9.5
Financecompleted value covers conversion cost with 12% to spare, which tops out the component	100	15%	15.0

Most of what it earns comes from daylight efficiency, and what holds it back most is scale, at 63 out of 100: 95 estimated homes, scored from 0 up to 150.

Built in 1972

San Francisco records this building as going up in 1972, 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 100% daylight figure above deserves.

What the conversion would cost

$405 per square foot all-in across 89,536 sq ft of converted floor, or $36.3M in total — about $382K for each of the 95 homes.

All-in cost per square foot for 350 Post 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 95 homes is $34.8M.

What would have to be true

A $1.5M gap before any grant, which the modeled $5.7M closes. What would reopen it soonest: circulation efficiency 10% down.

The shortfall before any grant is $1.5M. Closing it from the value side means each of the 95 homes finishing at $382K rather than the $366K the model assumes — 4% more. Closing it from the cost side means getting all-in cost down from $405 to $388 per square foot.

A modeled RESIDE grant of $5.7M moves that threshold to $322K 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 350 Post St:

Single-assumption flip points for 350 Post St, each holding the other three at their defaults.

Circulation efficiencythe binding constraint — the least this building would need	10% downto 72%
Average unit size	11% upto 833 sq ft
Completed value per home	12% downto $322K
Conversion cost per square foot	18% upto $307/sq ft

All four are sliders in the survey, where 350 Post St re-scores against your own numbers.

How it compares in Downtown San Francisco

350 Post St ranks 37th 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 78% of them at its deepest interior point. On size it is the 128th 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-R zone

35th of 165 in Financial District/South Beach, 3rd of 25 zoned C-3-R — the comparison that shares its rules, rents and streets.

San Francisco places 165 of the screened buildings in Financial District/South Beach. 350 Post St ranks 35th 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 32 ft, and together they would hold an estimated 40,456 homes. The group’s top scorer is 870 Market St, at 100.

25 of the screened buildings are zoned C-3-R. 350 Post St ranks 3rd of them against a median score of 90. 21 score 70 or more, their median deepest interior point is 32 ft from a facade against this building’s 32 ft, and together they would hold an estimated 2,773 homes. The group’s top scorer is 870 Market St, at 100.

Its nearest match in size: 201 Grant Ave

The screened building closest to 350 Post St in converted floor area is 201 Grant Ave: 83,256 sq ft over 11 stories, against 89,536 sq ft over 11 here.

The two land within a few points of each other — 95 here, 94 there — so at this size the screen reads them as much the same prospect. On the money they sit in the same place: each pencils only with the modeled RESIDE grant. The two stand about 600 ft apart.

Would it qualify for a RESIDE Act grant?

The model awards 350 Post St $5.7M, 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.