How much sun will an NYC apartment get?

In December the sun in New York never climbs above 26 degrees, so the building across the street can shade a window all day. The direction, the floor and the neighbors decide it.

Updated 2026-10-21

Why December is the month to check

On December 21 the sun rises a little after 7:15 in the morning and sets around 4:30, and at noon it stands 26 degrees above the horizon. At that angle a building’s shadow is about twice as long as the building is tall. In March the noon sun is at 49 degrees and in June at 73, so summer sun reaches almost any window that faces it. Listing photos are often taken in summer.

Which way the windows face

In winter the sun crosses the southern sky, from southeast in the morning to southwest in the afternoon. Windows facing south get the most; east gets the morning, west the afternoon, and north none in December. Manhattan’s street grid is turned about 29 degrees east of true north, so on a cross street the “south-facing” side actually faces south-southeast and gets its sun before early afternoon.

The floor and the buildings across

A building across the street shades your window when it is taller than your window plus the street’s width times the steepness of the sun. In December at noon that steepness is 0.49. Most Manhattan cross streets are 60 feet wide, about 18 meters:

Morning and afternoon sun is lower still, so the shade reaches further. A tower 150 meters away can still block a low window at 8:30 on a December morning.

How to check

1. Find which way the windows face, with a map or a phone compass.
2. Look at what is across from them: how tall, and how far. The city’s building footprints carry every roof’s measured height.
3. Visit at the hours you’d be home, in winter if you can.
4. Ask which floor and which side the apartment is on. Walls shared with the next building have no windows.

What Pigeon shows

Pigeon takes every outside wall of the building from the city’s footprint data and checks it against the measured roof height of every building within 250 meters, for each floor and each hour of December 21, March 20 and June 21. The Light score is the December sun on the listing’s floor, on the building’s brightest side. Which side the apartment is on isn’t public, so Pigeon shows every side rather than guess. At 8:30 on a December morning, a 27-story tower 158 meters away still shades the 3rd floor of 255 West 75th Street.