Neighborhoods have acoustical patterns

When planners approve a new structure, it has to fit the zoning requirements for that neighborhood. Those requirements could include building height, lot depth, square footage, number of units, open space, parking, and trees. But rarely do they consider the acoustics and noise patterns in the area. They might not even be aware of them.

Every neighborhood has acoustical patterns. And every new element in that neighborhood can affect those acoustics. For example, consider a neighborhood where the homes are 1-2 stories high. If you build a new home that’s 3-4 stories high, it could make an acoustical impact on the area. Depending on the terrain, noise might bounce off the taller structure.

Adding density adds noise

Noise issues can affect neighborhoods where city planners encourage infill — that is, building a second home into the open space behind an existing home. To offer a view, the second home might be taller than the one in front of it, with an exterior deck. The deck provides some outdoor enjoyment when there’s no yard available. But this option might come with a price — often paid by the neighbors.

Terrain and acoustics

A large multi-unit apartment building on a wider boulevard might not make a significant noise impact on the neighborhood, even if each apartment has a balcony. But compare that to a tall home in a residential neighborhood with narrow streets. Looming above the neighboring homes, an open deck could make a noticeable sonic difference. Likewise, a neighborhood with a flat terrain might be less impacted by noise than a neighborhood with hills, which often creates an amphitheater effect.

Decks and the people who use them

Decks don’t cause noise. People do. And if residents are considerate and self-aware, they might use their urban decks for quieter activities or be mindful and stay indoors at night. What city dweller doesn’t want a little space to sit outdoors and enjoy some fresh air?

However, decks with views are a huge attraction for parties. And people who party often love to drink, and some people who drink also love to smoke. And where do you find smokers? On the deck. If you have neighbors who like to throw big parties until the wee hours, you might have a noise problem.

Example: luxury homes with party decks

The four San Francisco luxury homes in this photo offer a perfect example of how developers can affect the quality of life in a neighborhood by changing the acoustics (as well as the demographics). Formerly an open space near a park, the owners cleared the trees off the lot and developed it into four tall homes: two in the front and two in the back. Because there’s no open space between these homes, the developers added exterior decks. You can see seven of them in this photo.

Photo of luxury homes with party balconies
These outdoor balconies are often filled with partygoers.

Each of these buildings is a separate, multistory single home. And naturally, the people who live in these homes or rent them through Airbnb have lots of money and space for throwing parties. And that’s exactly how some of these balconies get used.

These buildings sit on a hill facing down into a labyrinth of smaller homes nestled on narrow streets. Neighbors can hear the partygoers on the balconies across a wide radius, up to several blocks away. If these buildings were nightclubs, they’d have restrictions on noise levels, hours of operation, impact on the neighbors, and patron behavior. But these restrictions don’t apply to homeowners, or else they’re not enforced. And they weren’t anticipated when the homes were built.

Strategies for urban balconies

So what can neighbors do? Wear earplugs, keep their windows shut, call the police, install soundproof windows, and advocate for more residential neighborhood guidelines. Make sure that any existing noise ordinances get enforced. If you don’t have noise guidelines in your city, advocate for them. And make your city planners aware of the acoustical environment of the neighborhoods so they enforce building requirements accordingly. For example, the city might need to restrict balconies at a certain elevation or enclose the balconies in glass.

Corridors of noise

When I visited Paris, I usually liked to stay in an apartment on a narrow side street. The neighborhood was fairly quiet until a car or motorcycle drove by, or until a group of people had a conversation outside. The street was lined with tall, Haussmann-era buildings on both sides. The sound bounced off the stone facades from one side to the other, creating a corridor of noise. Furthermore, the original 19th-century windows were thin and didn’t close properly.

photo of a street in Paris
A side street in Paris where — acoustically — any noise became a loud noise.

Any noise on the street could be very disruptive in the dead of night. It sounded like the windows were open. Surely the city planners in the late 1800s didn’t have this in mind when they designed this dense housing. And they didn’t anticipate modern noise, like motorized cars with stereos and subwoofers. I wasn’t the only person impacted by street noise, and more recently, Paris has been enforcing some of its noise rules for clubs.

The identically tall buildings look impressive. They’ve withstood the test of time. But without varying the heights or the facades of the buildings and without any openings, these long corridors create a wall of sound. These same buildings would be acoustically less impactful if they were on a wider boulevard. If this same street was designed today, it might benefit from staggering the facades and creating setbacks for some of the upper floors.

Planning for noise

As citizens, you can contribute to the knowledge base for city planners by mapping the noise in your area. Street by street, how loud or quiet is it? Use an app like Hush City to map it during the day and again at night. Take note of the most-frequent noises: car/motorcycle and Uber traffic, delivery trucks, sanitation, partygoers, skateboarders, construction. What are the acoustical attributes of this area? Get active: make sure your city planners keep areas livable and anticipate that some people won’t self-monitor their behavior. Cities are a work in progress. You can be an ambassador for better urban planning!

Planning for noise