48-52 Boylston St

48-52 Boylston St is a 7-story apartment building in Downtown Boston. Its floor plate has 100% of its area within daylight reach of a facade and scores 91 out of 100 on this screen’s measures, which is part of why it works as housing.

MA-7 & MA-8 · Screened 2026-10-04 · Already housing

Where 48-52 Boylston St is

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

Suitability score

0–29

30–49

50–69

70–100

Already housing
Not screened
48-52 Boylston St

48-52 Boylston St and the 1,000 ft of Downtown Boston 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. 48-52 Boylston St is outlined in its own score color at the outline it covers at ground level. Dashed inside it is the typical floor, the one the floor-plate figure below draws, because this building steps back as it rises. The inset places it among every building the screen covers.

Typical floor plan: 100% of the building’s floor area sits within daylight reach of a facade; the drawing shows its typical floor, where the share is 100%, 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, 28 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 steps are where the building sets back as it rises. The shaded ground floor is converted like the rest and counted as no homes.

This is already housing: Boston's assessing records list an apartment building whose unit count they do not record here. It is on the map because a record on the same parcel carries an office land-use code, but this site does not count it as a conversion candidate.

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 48-52 Boylston St, 2026-10-04.

Suitability scoreStrong candidate	91 / 100
Storiesfrom 78 ft aerial-survey height ÷ 12 ft floor-to-floor	7
Height bandsfloor plate by floor range, from the city's roof outlines	Floors 1–6: 10,832 sq ft · Floor 7: 3,468 sq ft
Floor platetypical floor, from the city outlines	10,832 sq ft
Daylight efficiencyshare within 35 ft of a facade	100%
Deepest interior pointviability threshold is 80 ft	28 ft
Windowless coretypical floor; the building-wide total is in the text above	0 sq ft
BuiltBoston's own record of the construction year	1899
ZoningDowntown Boston	SKY
Opportunity Zonenot in a 2018 designated tract	No

The plan: window line, shape and floor rhythm

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

The typical floor has 590 ft of exterior wall, and across 6 residential floors the building carries 3,195 ft of it in total, divided among the 61 homes this screen estimates.

Its plate is elongated at 0.39: 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 10.2 homes per floor, repeated on every residential floor, since this building's outline does not change as it rises.

Why 48-52 Boylston St scores 91 out of 100

Daylight efficiency 100, Interior depth 100, Scale 41, Finance 100 — each out of 100, then weighted.

Score components for 48-52 Boylston 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 28 ft from a facade, scored from 80 ft down to 40 ft	100	25%	25.0
Scale61 estimated homes, scored from 0 up to 150	41	15%	6.1
Financecompleted value covers conversion cost with 47% 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 41 out of 100: 61 estimated homes, scored from 0 up to 150.

Built in 1899

Boston records this building as going up in 1899, 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 100% daylight figure above deserves.

Other buildings screened near 48-52 Boylston St

The 4 closest the screen also covers, from 580 ft away. They are the colored outlines on the plan at the top of this page.

588-622 Washington St
8 stories · 53% daylit · 199 estimated homes · scores 35/100 (Marginal)
about 580 ft away
252-272 Tremont St
13 stories · 100% daylit · 141 estimated homes · scores 99/100 (Strong candidate)
about 650 ft away
99 Chauncy St
11 stories · 97% daylit · 178 estimated homes · scores 98/100 (Strong candidate)
about 820 ft away
2 Park Plz
7 stories · 100% daylit · 39 estimated homes · scores 89/100 (Strong candidate)
about 860 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.