150 Post St

150 Post St is a 7-story building in Downtown San Francisco with 86% of its floor area within daylight reach of a facade. This screen estimates 81 homes and scores it 82 out of 100 for office-to-residential conversion suitability.

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

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Where 150 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
150 Post St

150 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. 150 Post St is outlined in its own score color at the outline it covers at ground level. Its windowless core is hatched. The inset places it among every building the screen covers.

Floor plan: 86% of each floor sits within daylight reach of a facade. The shading is daylight, darkest at the windows and gone 35 ft in. The hatched area is windowless core: 2,078 sq ft per floor that must be renovated but can never be rented as an apartment. The dimension marks the deepest interior point, 50 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, fading as it goes, and the hatched stripe left between the lit edges is floor that gets converted and can never be rented: 2,078 sq ft on the floor the screen scores, and 12,470 sq ft over 6 residential floors. The shaded ground floor is converted like the rest and counted as no homes.

This building does not pencil at default assumptions, even with a modeled RESIDE Act grant.

Every floor carries 2,078 sq ft of windowless core — area that must be gutted, seismically braced and sprinklered but can never be rented as an apartment. Across 6 residential floors that is 12,470 sq ft of cost carrying no revenue.

Modeled conversion metrics for 150 Post St, 2026-10-12.

Suitability scoreStrong candidate	82 / 100
Storiesfrom 105 ft LiDAR (2010) height ÷ 12 ft floor-to-floor	7
Floor plateper floor, from the city footprint	14,852 sq ft
Daylight efficiencyshare within 35 ft of a facade	86%
Deepest interior pointviability threshold is 80 ft	50 ft
Windowless coreper floor — renovated but never rentable	2,078 sq ft
Estimated homesat 750 sq ft average	81
Conversion cost$405/sq ft all-in on 89,114 sq ft	$36.1M
Gap before grantshortfall against completed value	$6.4M
Modeled RESIDE grantbelow the statutory cap	$4.9M
BuiltSan Francisco's own record of the construction year	1908
ZoningFinancial District/South Beach	C-3-R
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 515 ft of exterior wall, and across 6 residential floors the building carries 3,088 ft of it in total, divided among the 81 homes this screen estimates.

Its plate is moderately compact at 0.70: 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 13.5 homes per floor, repeated on every residential floor, since this building's outline does not change as it rises.

Why 150 Post St scores 82 out of 100

Daylight efficiency 92, Interior depth 76, Scale 54, Finance 93 — each out of 100, then weighted.

Score components for 150 Post St. Points are the subscore times its weight.

Component	Subscore	Weight	Points
Daylight efficiency86% of the floor area within 35 ft of a facade, scored from 40% up to 90%	92	45%	41.4
Interior depthdeepest interior point 50 ft from a facade, scored from 80 ft down to 40 ft	76	25%	18.9
Scale81 estimated homes, scored from 0 up to 150	54	15%	8.1
Financeremaining gap is 4% of conversion cost, scored from 60% down to 0%	93	15%	13.9

Most of what it earns comes from daylight efficiency, and what holds it back most is scale, at 54 out of 100: 81 estimated homes, scored from 0 up to 150.

Built in 1908

San Francisco records this building as going up in 1908, which puts it in the pre-1920 stock.

As a rule, the era that converts most readily: load-bearing masonry, small floor plates laid out before deep-plan offices were possible, operable windows and generous floor-to-floor heights. The usual obstacles are not daylight but hazardous materials, lifts and bringing structure up to current code. 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 86% daylight figure above deserves.

What the conversion would cost

$405 per square foot all-in across 89,114 sq ft of converted floor, or $36.1M in total — about $446K for each of the 81 homes.

All-in cost per square foot for 150 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 12,470 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 81 homes is $29.6M.

What would have to be true

A $6.4M gap before any grant, $1.6M after the modeled one. The smallest single change that would close it: average unit size 4% down.

The shortfall before any grant is $6.4M. Closing it from the value side means each of the 81 homes finishing at $446K rather than the $366K the model assumes — 22% more. Closing it from the cost side means getting all-in cost down from $405 to $333 per square foot.

A modeled RESIDE grant of $4.9M moves that threshold to $386K a home. That is still above the $366K assumed, leaving $1.6M uncovered, which is why the grant does not unlock this one.

Nor do all four levers have to move. For 150 Post St, one alone would close the gap at:

Single-assumption flip points for 150 Post St, each holding the other three at their defaults.

Average unit sizethe binding constraint — the least this building would need	4% downto 721 sq ft
Circulation efficiency	4% upto 83%
Completed value per home	5% upto $386K
Conversion cost per square foot	7% downto $242/sq ft

All four are sliders in the survey, where 150 Post St re-scores against your own numbers.

How it compares in Downtown San Francisco

150 Post St ranks 120th of the 205 buildings screened here, against a median score of 87.

Its floor plate is better lit than 46% of them, and shallower than 49% of them at its deepest interior point. On size it is the 136th 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

100th of 165 in Financial District/South Beach, 20th 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. 150 Post St ranks 100th 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 50 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. 150 Post St ranks 20th 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 50 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: 979 Market St

The screened building closest to 150 Post St in converted floor area is 979 Market St: 87,248 sq ft over 6 stories, against 89,114 sq ft over 7 here.

150 Post St scores 82 to its 75, and with the size held roughly equal most of that lead comes from daylight efficiency: 92 out of 100 here, 83 there (82% of the floor area within 35 ft of a facade, scored from 40% up to 90%). On the money they sit in the same place: each falls short even with the modeled grant. The two stand about 2,800 ft apart.

Would it qualify for a RESIDE Act grant?

The model awards 150 Post St $4.9M, 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.