Sunlight wields enormous power in our interior spaces. It can drive up the value of real estate and alter the mood of a room. It can clarify the work on your desktop and create warmth on a cool day. No light bulb can do all that.

Natural light has long shaped how buildings are designed and constructed for these reasons. And as we described in this recent Upshot project, light is a big part of why it’s so hard to convert many office buildings into housing. In short, apartments require daylight. And the deep interior of the big modern office hasn’t got it.

It takes only a quick scan of real estate listings to see the instinctive (and commercial) hold that sunlight has over us.

Over the course of our reporting, we came to think about this light — distinct from the blaze of a fluorescent light bulb — as the warm glow in a Vermeer painting. Dan Kaplan, a New York architect, put this idea in our heads.

When thinking about what an apartment wants that a modern office building often lacks, he wrote in an email:

“The ideal interior condition that you are getting at is perhaps best represented by those beautiful Vermeer paintings (‘The Music Lesson,’ ‘The Milkmaid,’ ‘The Geographer,’ etc.): tall windows (open!), letting soft light fall deeply into tall-ceilinged but relatively shallow rooms.”

Truly the man loved his window light:

Art history textbooks often call Vermeer the “master of light,” and you can see why. The subjects he paints aren’t particularly remarkable. But with great natural light, even everyday scenes become transcendent (and Vermeer’s geographer looks as if he’s had a mapping epiphany).

Vermeer’s light is not the mysterious holy light of a religious painting, but the ordinary daylight that floods through an open window. The farther you get from the window, the more that light dissipates. You can see that in the gentle gradient of Vermeer’s walls:

Architects and builders have historically thought about light — and even tried to measure it — in terms that echo this gradient. Before modern lighting, the appeal and potential profitability of an office building depended on tall ceilings and large windows capable of lighting as much interior work space as possible. This graph, reprinted in the architectural historian Carol Willis’s book “Form Follows Finance,” was originally published in a 1925 issue of Buildings and Building Management (a “foot candle” here is a lumen per square foot):

Even on sunny days, once you’re more than 25 to 30 feet from a window, there’s little light to speak of. And without natural light, your best alternative in the early 20th century was a weak task lamp with a hot incandescent bulb.

The reach of daylight meant that homes and office suites built before modern lighting seldom had spaces farther than 25 to 30 feet from a window. Over the years, however, new technology — structural supports, air-conditioning, artificial light — enabled us to move away from that standard, and from the Vermeer ideal.

Today many people work in cubicles far from the nearest window, often in environments where they’re unaware of the weather (or the setting sun). In the modern office, Vermeer’s window light is now an array of ceiling-mounted fluorescent light tubes. Imagine our pensive geographer in such a setting.

While we have generally accepted windowless office life, we have tended to balk at windowless living. The mere suggestion evokes crowded tenements (and real safety concerns).

Many readers responding to our story have suggested that while cities are now trying to repurpose office buildings, it might also be time to reconsider our tolerance for windowless office work. Seen through a historical lens, our sunless workdays are the aberration.

The geographer needed a window in 1669, just like the insurance adjuster in 1910, and the one-bedroom tenant in 2023. And like Vermeer did, by the way, to paint.

Now keep him in mind as you read this article on what it takes to turn office buildings into homes.