1801 Blake St
1801 Blake St is a 8-story building in Greater Downtown Denver with 71% of its floor area within daylight reach of a facade. This screen estimates 364 homes and scores it 56 out of 100 for office-to-residential conversion suitability.
CO-1 · Screened 2026-09-19 · Worth a feasibility study
Also addressed as 1805 Blake St, 1809 Blake St, 1821 Blake St, 1825 Blake St, 1855 Blake St, 1800 Wazee St, 1850 Wazee St and 1890 Wazee St: Denver’s address records place all 9 on this one footprint.
Where 1801 Blake St is
Its block in Greater Downtown Denver, drawn from Denver's own building outlines and street centerlines.
- Already housing
- Not screened
- 1801 Blake St
This building does not pencil at default assumptions, even with a modeled RESIDE Act grant.
Across its 7 residential floors this building carries 142,773 sq ft of windowless core — area that must be gutted, re-plumbed and sprinklered but can never be rented as an apartment.
Read with caution. This footprint carries 9 street addresses across 67,999 sq ft, which usually means the city’s GIS has merged a block or complex into a single polygon rather than describing one convertible building.
Modeled conversion metrics for 1801 Blake St, 2026-09-19.
| Suitability scoreWorth a feasibility study | 56 / 100 |
|---|---|
| Storiesfrom 98 ft aerial-survey height ÷ 12 ft floor-to-floor | 8 |
| Height bandsfloor plate by floor range, from the city's roof outlines | Floors 1–2: 98,149 sq ft · Floor 3: 97,801 sq ft · Floors 4–5: 67,999 sq ft · Floor 6: 58,796 sq ft · Floor 7: 52,966 sq ft · Floor 8: 40,807 sq ft |
| Floor platetypical floor, from the city outlines | 67,999 sq ft |
| Daylight efficiencyshare within 35 ft of a facade | 71% |
| Deepest interior pointviability threshold is 80 ft | 65 ft |
| Windowless coretypical floor; the building-wide total is in the text above | 20,711 sq ft |
| Estimated homesat 750 sq ft average | 364 |
| Conversion cost$360/sq ft all-in on 484,517 sq ft | $174.4M |
| Gap before grantshortfall against completed value | $88.5M |
| Modeled RESIDE grantat the statutory per-award cap | $10.0M |
| BuiltDenver does not publish a construction year with this data | — |
| ZoningUnion Station | D-LD |
| Opportunity Zonenot in a 2018 designated tract | No |
The plan: window line, shape and floor rhythm
31 ft of exterior wall for each home the screen estimates — enough for two- and three-bedroom homes across the plan.
The typical floor has 1,558 ft of exterior wall, and across 7 residential floors the building carries 11,453 ft of it in total, divided among the 364 homes this screen estimates.
Its plate is elongated at 0.35: 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 52.0 homes per floor. Its floors are not alike, though: the typical floor's deepest interior point is 65 ft from a facade, while its worst floor reaches 67 ft. The score follows the typical floor, so a podium that could not hold a bedroom does not by itself sink a slim tower above it — but it is there, and it is part of what would have to be drawn around.
Why 1801 Blake St scores 56 out of 100
Daylight efficiency 61, Interior depth 37, Scale 100, Finance 25 — each out of 100, then weighted.
Score components for 1801 Blake St. Points are the subscore times its weight.
| Component | Subscore | Weight | Points |
|---|---|---|---|
| Daylight efficiency71% of the floor area within 35 ft of a facade, scored from 40% up to 90% | 61 | 45% | 27.5 |
| Interior depthdeepest interior point 65 ft from a facade, scored from 80 ft down to 40 ft | 37 | 25% | 9.4 |
| Scale364 estimated homes, scored from 0 up to 150 | 100 | 15% | 15.0 |
| Financeremaining gap is 45% of conversion cost, scored from 60% down to 0% | 25 | 15% | 3.7 |
Most of what it earns comes from daylight efficiency, and what holds it back most is finance, at 25 out of 100: remaining gap is 45% of conversion cost, scored from 60% down to 0%.
What the conversion would cost
$360 per square foot all-in across 484,517 sq ft of converted floor, or $174.4M in total — about $479K for each of the 364 homes.
All-in cost per square foot for 1801 Blake St: base cost plus the code work a change of use triggers.
| Base conversion cost | $260/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 | $360/sq ft |
That cost is charged across every converted square foot, including the 142,773 sq ft of windowless core, which has to be gutted, re-plumbed and sprinklered like the rest of the building and then earns nothing. Against it the model sets a completed value of $236K a home, which for 364 homes is $85.9M.
What would have to be true
A $88.5M gap before any grant, $78.5M after the modeled one. The smallest single change that would close it: average unit size 48% down.
The shortfall before any grant is $88.5M. Closing it from the value side means each of the 364 homes finishing at $479K rather than the $236K the model assumes — 103% more. Closing it from the cost side means getting all-in cost down from $360 to $177 per square foot.
A modeled RESIDE grant of $10.0M moves that threshold to $452K a home. That is still above the $236K assumed, leaving $78.5M uncovered, which is why the grant does not unlock this one.
Nor do all four levers have to move. For 1801 Blake St, one alone would close the gap at:
Single-assumption flip points for 1801 Blake St, each holding the other three at their defaults.
| Average unit sizethe binding constraint — the least this building would need | 48% downto 392 sq ft |
|---|---|
| Conversion cost per square foot | 62% downto $98/sq ft |
| Completed value per home | 91% upto $452K |
All four are sliders in the survey, where 1801 Blake St re-scores against your own numbers.
How it compares in Greater Downtown Denver
1801 Blake St ranks 182nd of the 214 buildings screened here, against a median score of 72.
Its floor plate is better lit than 14% of them, and shallower than 15% of them at its deepest interior point. On size it is the 55th largest by estimated homes. The full survey of all 214 buildings ranks and maps every one of them, and the list by address links each to its own page.
Within Union Station and the D-LD zone
49th of 55 in Union Station, 27th of 29 zoned D-LD — the comparison that shares its rules, rents and streets.
Denver places 55 of the screened buildings in Union Station. 1801 Blake St ranks 49th of them against a median score of 69. 23 score 70 or more, their median deepest interior point is 61 ft from a facade against this building’s 65 ft, and together they would hold an estimated 13,167 homes. The group’s top scorer is 1600 17th St, at 95.
29 of the screened buildings are zoned D-LD. 1801 Blake St ranks 27th of them against a median score of 68. 10 score 70 or more, their median deepest interior point is 61 ft from a facade against this building’s 65 ft, and together they would hold an estimated 5,069 homes. The group’s top scorer is 1600 17th St, at 95.
Its nearest match in size: 3600 Blake St
The screened building closest to 1801 Blake St in converted floor area is 3600 Blake St: 493,252 sq ft over 10 stories, against 484,517 sq ft over 8 here.
The two land within a few points of each other — 56 here, 56 there — so at this size the screen reads them as much the same prospect. On the money they sit in the same place: each falls short even with the modeled grant. The two stand about 8,600 ft apart.
Would it qualify for a RESIDE Act grant?
The model awards 1801 Blake 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 1801 Blake St
The 4 closest the screen also covers, from 270 ft away. They are the colored outlines on the plan at the top of this page.
- 1441 18th St12 stories · 88% daylit · 200 estimated homes · scores 78/100 (Strong candidate)about 270 ft away
- 1863 Wazee St7 stories · 82% daylit · already a condominium buildingabout 310 ft away
- 1755 Blake St5 stories · 75% daylit · 85 estimated homes · scores 58/100 (Worth a feasibility study)about 400 ft away
- 1621 18th St6 stories · 73% daylit · 88 estimated homes · scores 60/100 (Worth a feasibility study)about 430 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.