680 Folsom St

Where 680 Folsom St is

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

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 743 ft of exterior wall, and across 13 residential floors the building carries 9,661 ft of it in total, divided among the 292 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 22.5 homes per floor, repeated on every residential floor, since this building's outline does not change as it rises.

Why 680 Folsom St scores 60 out of 100

Daylight efficiency 57, Interior depth 45, Scale 100, Finance 54 — each out of 100, then weighted.

Most of what it earns comes from daylight efficiency, and what holds it back most is interior depth, at 45 out of 100: deepest interior point 62 ft from a facade, scored from 80 ft down to 40 ft.

Built in 1964

San Francisco records this building as going up in 1964, which puts it in the post-war stock.

As a rule, the period when plates got deep and facades became curtain wall: sealed glazing, lower floor-to-floor heights, and mechanical systems designed around a sealed box. Conversions here usually turn on whether the windows can be made to open and whether ceilings survive new plumbing. 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 69% daylight figure above deserves.

What the conversion would cost

$405 per square foot all-in across 399,737 sq ft of converted floor, or $161.9M in total — about $554K for each of the 292 homes.

That cost is charged across every converted square foot, including the 125,356 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 292 homes is $106.9M.

What would have to be true

A $55.0M gap before any grant, $45.0M after the modeled one. The smallest single change that would close it: average unit size 30% down.

The shortfall before any grant is $55.0M. Closing it from the value side means each of the 292 homes finishing at $554K rather than the $366K the model assumes — 51% more. Closing it from the cost side means getting all-in cost down from $405 to $267 per square foot.

A modeled RESIDE grant of $10.0M moves that threshold to $520K a home. That is still above the $366K assumed, leaving $45.0M uncovered, which is why the grant does not unlock this one.

Nor do all four levers have to move. For 680 Folsom St, one alone would close the gap at:

All four are sliders in the survey, where 680 Folsom St re-scores against your own numbers.

How it compares in Downtown San Francisco

680 Folsom St ranks 177th of the 205 buildings screened here, against a median score of 87.

Its floor plate is better lit than 9% of them, and shallower than 26% of them at its deepest interior point. On size it is the 55th 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

145th of 165 in Financial District/South Beach, 52nd 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. 680 Folsom St ranks 145th 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 62 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). 680 Folsom St ranks 52nd 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 62 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: 101 Market St

The screened building closest to 680 Folsom St in converted floor area is 101 Market St: 386,849 sq ft over 12 stories, against 399,737 sq ft over 14 here.

680 Folsom St scores 60 to its 57, and with the size held roughly equal most of that lead comes from daylight efficiency: 57 out of 100 here, 53 there (66% 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 3,200 ft apart.

Would it qualify for a RESIDE Act grant?

The model awards 680 Folsom 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 680 Folsom St

The 4 closest the screen also covers, from 250 ft away. They are the colored outlines on the plan at the top of this page.

• 95 Hawthorne St
  5 stories · 81% daylit · 57 estimated homes · scores 70/100 (Strong candidate)
  about 250 ft away
• 75 Hawthorne St
  20 stories · 72% daylit · 330 estimated homes · scores 61/100 (Worth a feasibility study)
  about 350 ft away
• 55 Hawthorne St
  11 stories · 89% daylit · 163 estimated homes · scores 94/100 (Strong candidate)
  about 380 ft away
• 201 3rd St
  12 stories · 67% daylit · 221 estimated homes · scores 52/100 (Worth a feasibility study)
  about 410 ft away