44 S 4th St

44 S 4th St is a 8-story building in Downtown San Jose with 62% of its floor area within daylight reach of a facade. This screen estimates 230 homes and scores it 49 out of 100 for office-to-residential conversion suitability.

CA-18 · Screened 2026-09-12 · Marginal

Build a conversion planCheck its numbers, lay out its homes and get a two-page PDF. Free.

Also addressed as 88 S 4th St: San Jose’s address records place both on this one footprint.

Where 44 S 4th St is

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

100 E Santa Clara St: scores 93 out of 100101 E San Fernando St: already housing100 E San Fernando St: already housing9349S 4th StS 5th StE San Fernando StN100 ftDowntown San Jose
Suitability score
0–29
30–49
50–69
70–100
  • Already housing
  • Not screened
  • 44 S 4th St
44 S 4th St and the 1,000 ft of Downtown San Jose 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. 44 S 4th 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.
73 ftAA100 ftDaylit 62%Core 18,783 sq ft
Floor plan: 62% 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: 18,783 sq ft per floor that must be renovated but can never be rented as an apartment. The dimension marks the deepest interior point, 73 ft from the nearest window. A–A is where the section beside it is cut.
No homesWindowless coreDaylit8 floors50 ft
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: 18,783 sq ft on the floor the screen scores, and 131,483 sq ft over 7 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 18,783 sq ft of windowless core — area that must be gutted, seismically braced and sprinklered but can never be rented as an apartment. Across 7 residential floors that is 131,483 sq ft of cost carrying no revenue.

Modeled conversion metrics for 44 S 4th St, 2026-09-12.

Suitability scoreMarginal49 / 100
Storiesfrom 99 ft LiDAR height ÷ 12 ft floor-to-floor8
Floor plateper floor, from the city footprint49,707 sq ft
Daylight efficiencyshare within 35 ft of a facade62%
Deepest interior pointviability threshold is 80 ft73 ft
Windowless coreper floor — renovated but never rentable18,783 sq ft
Estimated homesat 750 sq ft average230
Conversion cost$405/sq ft all-in on 347,946 sq ft$140.9M
Gap before grantshortfall against completed value$43.2M
Modeled RESIDE grantat the statutory per-award cap$10.0M
BuiltSan Jose does not publish a construction year with this data—
ZoningDowntown San JoseDC
Opportunity Zonecensus tract 06085500901, 2018 designationYes

The plan: window line, shape and floor rhythm

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

The typical floor has 1,080 ft of exterior wall, and across 7 residential floors the building carries 7,557 ft of it in total, divided among the 230 homes this screen estimates.

Its plate is moderately compact at 0.54: 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 32.9 homes per floor, repeated on every residential floor, since this building's outline does not change as it rises.

Why 44 S 4th St scores 49 out of 100

Daylight efficiency 44, Interior depth 17, Scale 100, Finance 61 — each out of 100, then weighted.

Score components for 44 S 4th St. Points are the subscore times its weight.

ComponentSubscoreWeightPoints
Daylight efficiency62% of the floor area within 35 ft of a facade, scored from 40% up to 90%4445%20.0
Interior depthdeepest interior point 73 ft from a facade, scored from 80 ft down to 40 ft1725%4.4
Scale230 estimated homes, scored from 0 up to 15010015%15.0
Financeremaining gap is 24% of conversion cost, scored from 60% down to 0%6115%9.1

Most of what it earns comes from daylight efficiency, and what holds it back most is interior depth, at 17 out of 100: deepest interior point 73 ft from a facade, scored from 80 ft down to 40 ft.

What the conversion would cost

$405 per square foot all-in across 347,946 sq ft of converted floor, or $140.9M in total — about $613K for each of the 230 homes.

All-in cost per square foot for 44 S 4th 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 131,483 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 $425K a home, which for 230 homes is $97.8M.

What would have to be true

A $43.2M gap before any grant, $33.2M after the modeled one. The smallest single change that would close it: average unit size 25% down.

The shortfall before any grant is $43.2M. Closing it from the value side means each of the 230 homes finishing at $613K rather than the $425K the model assumes — 44% more. Closing it from the cost side means getting all-in cost down from $405 to $281 per square foot.

A modeled RESIDE grant of $10.0M moves that threshold to $569K a home. That is still above the $425K assumed, leaving $33.2M uncovered, which is why the grant does not unlock this one.

Nor do all four levers have to move. For 44 S 4th St, one alone would close the gap at:

Single-assumption flip points for 44 S 4th St, each holding the other three at their defaults.

Average unit sizethe binding constraint — the least this building would need25% downto 560 sq ft
Completed value per home34% upto $569K
Conversion cost per square foot37% downto $165/sq ft

All four are sliders in the survey, where 44 S 4th St re-scores against your own numbers.

How it compares in Downtown San Jose

44 S 4th St ranks 56th of the 82 buildings screened here, against a median score of 64.

Its floor plate is better lit than 29% of them, and shallower than 38% of them at its deepest interior point. On size it is the 33rd largest by estimated homes. The full survey of all 82 buildings ranks and maps every one of them, and the list by address links each to its own page.

Within the DC zone

47th of 72 zoned DC — the comparison that shares its rules, rents and streets.

72 of the screened buildings are zoned DC. 44 S 4th St ranks 47th of them against a median score of 61. 31 score 70 or more, their median deepest interior point is 68 ft from a facade against this building’s 73 ft, and together they would hold an estimated 23,276 homes. The group’s top scorer is 1 Almaden Blvd, at 100.

Its nearest match in size: 52 E Santa Clara St

The screened building closest to 44 S 4th St in converted floor area is 52 E Santa Clara St: 343,638 sq ft over 6 stories, against 347,946 sq ft over 8 here.

44 S 4th St scores 49 and 52 E Santa Clara St only 35, and the difference is a hard fail rather than a matter of degree: the lower one is capped at 35 because its deepest interior point is 90 ft from a facade, past the 80 ft threshold beyond which conversion requires carving a light well. On the money they sit in the same place: each falls short even with the modeled grant. The two stand about 800 ft apart.

Would it qualify for a RESIDE Act grant?

The model awards 44 S 4th 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.

This building does sit in census tract 06085500901, a 2018 designated Opportunity Zone, which Section 201 lets HUD favor — one of the few statutory priorities this screen can actually check.

Other buildings screened near 44 S 4th St

The 4 closest the screen also covers, from 290 ft away. They are the colored outlines on the plan at the top of this page.

  • 101 E San Fernando St
    6 stories · 39% daylit · already an apartment building
    about 290 ft away
  • 100 E Santa Clara St
    6 stories · 91% daylit · 128 estimated homes · scores 93/100 (Strong candidate)
    about 540 ft away
  • 100 E San Fernando St
    6 stories · 39% daylit · already a condominium building
    about 560 ft away
  • 181 E Santa Clara St
    25 stories · 57% daylit · 819 estimated homes · scores 35/100 (Marginal)
    about 720 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.