Top Ten Walkable Cities

Just as birds were built to fly, humans were built to walk. The former mayor of Bogotá, Colombia, Enrique Peñalosa, said it best. He stated, “God made us walking animals, pedestrians. As a fish needs to swim, a bird to fly, a deer to run, we need to walk, not in order to survive, but to be happy.”

However, this concept does not hold true everywhere. Take for instance auto-centric cities such as Houston and Jakarta. As Jan Gehl, Danish architect and urban designer, believes, cities are meant for people, not cars.

Since summer is in full swing for a majority of the world, why not plan a trip with walkability in mind? Before booking, have a look at our most walkable destinations!

Freedom Trail, Boston

10. Boston, Massachusetts

As one of the oldest cities in the United States, it’s no surprise that Boston ranks as one of the most walkable cities. Whether you’re a history buff or just adventurous, take the 2.5-mile Freedom Trail, which leads to 16 historic sites. Perhaps you want a view? Walk along Harborwalk, where you’ll discover public art, parks, and cafes. The Beacon Hill neighborhood is also a top spot for walking, as it is along the Freedom Trail.

Pitt Street, Sydney

9. Sydney, Australia

Sydney has gorgeous weather for most of the year, making it a reasonable feat to cover on foot. Start at the Rocks on the edge of the city center, then proceed to Circular Quay and the Royal Botanic Gardens. Throughout, soak in the famous sights such as the Opera House and the Harbor Bridge. If you’re curious about the beaches, begin at Bondi Beach and walk two miles to Bronte, where you’ll be immersed amidst cliffs that line the Pacific Ocean. Stop at Manly or Tamarama Beach to partake in the art of people-watching.

Seawall, Vancouver

8. Vancouver, British Columbia

Vancouver is a dense, compact city, featuring a great public transportation network and a comprehensive system for pedestrians and bicyclists. Take a stroll on the beautiful False Creek shoreline promenade to Granville Island and enjoy the public market, shops, and cafes. Stanley Park, an expansive urban park bordering downtown Vancouver, presents stellar views, inner city beaches, public art, and other natural amenities.

Tango at San Telmo, Buenos Aires

7. Buenos Aires, Argentina

As you travel from the airport, Buenos Aires seems like a sprawling metropolis over the eastern plains of Argentina. However, there’s no need to worry, as the central city is well devised for walking. As you walk, it’s hard to miss presidential palaces and grand churches, spontaneous tango sessions, and commerce. Yet the neighborhoods of Buenos Aires cater to all, especially on a Sunday in San Telmo, which features a lively, bohemian market comprised of shops, street performers, and artists. If you’re in the mood for something more elegant, be sure to explore Palermo, an all cobble area with tree-lined streets, bursting with boutiques and restaurants.

Celetná Street, Prague

6. Prague, Czech Republic

Explore the Royal Route, which got its name from the coronation processions of the Bohemian kings. Begin your trek at Prasna Brana, part of the original gates of the old city, and follow the silver arrows on the sidewalks along Celetná Street. Throughout this journey, take in the wonders of the House of the Black Madonna, the first cubist building in Europe. Follow this path to Old Town Square to experience the Astronomical clock.

Heroes’ Square, Budapest

5. Budapest, Hungary

The Danube River bisects the city, and both sides present an abundance of walking opportunities centered on history. Begin at Heroes’ Square, which features lavish monuments. Then venture to Andrassy Avenue and make sure to stop at the baroque Széchenyi baths to engage in the city’s bathing culture. At night, take a pub crawl and visit the city’s “ruin pubs” such as Ötkert or Szimpla Kert, where you will discover how the Hungarians party.

La Rambla, Barcelona

4. Barcelona, Spain

La Rambla, an expansive tree-lined pedestrian mall, sits at the heart of Barcelona. Here you will discover shops, street performers, vendors, and restaurants, making it a memorable place to walk. Walk along the Barcelona harbor pedestrian area and continue until you reach the Plaça de Catalunya, the city’s central square. Seeking historic architecture? Check out Gothic Quarter, which features 15^th-century churches and plazas.

Camden High Street, London

3. London, United Kingdom

London is a collection of interesting neighborhoods, and it offers a plethora of attractive walks, including the Jubilee Walkway, London Loop, and Thames Path. Several companies offer guided tours that cover topics such as architecture, historic events, and ghosts. Often overlooked, the Regent district of London is a perfect location to walk, as it is situated along London’s inner canal system. With a comprehensive network of parks, historical attractions, and natural amenities, London is a walker’s dream.

Little Italy, NYC

2. New York City, New York

Take a stroll during rush hour on a weekday afternoon and you will spot fashionably dressed men and women sporting athletic shoes. New York is a walker’s paradise, and with gridded streets, which are clearly numbered, don’t worry about getting lost. Instead of establishing a set route, experience the city’s offerings through its distinct neighborhoods. The list of human-scaled neighborhoods best enjoyed by walking is lengthy, yet some of the best include: Village, Chelsea, SoHo, Upper West Side, East Village, and (how could you forget) Central Park! Expect to cover about 20 north-south blocks per mile at a moderate pace.

Pedestrian crossing in Paris

1. Paris, France

Packed with tree-lined streets, cobblestone side streets, sidewalk cafes, promenades along the Seine, and lanes blocked off to cars, Paris is an exhilarating city to experience by foot. An entire book can be written about walking in Paris, and it has already been done. So, instead, I will highlight a few key destinations. A favorite walking route is from Sacré-Coeur Basilicathrough Montmatre, where you will experience a weekend artists’ and produce market. If you are interested in palaces, gardens, and historic buildings, walk along the Right Bank of the Seine River, detouring slightly to absorb the Champs-Élysees and Place de la Concorde. However, I would recommend simply exploring, because intriguing experiences can be found throughout the city.

Although there are many walkable cities, I had to narrow it down to 10. Whether you’re an urbanist or a person interested in car-optional destinations, this list highlights exemplary locations where pedestrians flourish.

While not all cities are walkable, if you do live in a walkable environment and are uncertain of the value of walkability, I urge you to ditch your car for a month and discover the rewards, such as more discretionary income, less stress, and greater social interaction.

Car Free Life: Reaping the Health and Financial Benefits

Imagine your city with less cars, where people use public transportation, and walk or cycle to move around. This ideal world would bring many positive changes to our surroundings and  our communities such as less polluted cities, better health, more social contact and a faster method of travel.

The event!

Every September 22^nd is World Carfree Day, which encourages people from around the globe to practice activities that remind us that we do not have to accept a car dominated society; that we can use other ways to move through our cities. Ultimately, it seeks to provoke change in our everyday lives.

Every second and fourth Sunday of the month in Jakarta

This movement, originally from Europe, spread throughout the world and has become a common event. Nowadays we have Carfree Days every week (mostly on Sundays), an initiative created in Bogota, Colombia. A few years ago many cities in America also adopted the practice. It is occurring in more than 38 cities in 11 countries- a number that continues to grow. With the help of the government, restricting car use, some streets, where people run, play, bike, skate or simply walk, have generated positive results. For instance, this campaign has helped individuals achieve the recommended minimum weekly requirement of physical activity determined by the US Department of Health and Human Services.

Benefits all around

There are many arguments that support the use of cars. The main points come from a text called The Ten Myths of Automobile Dependence by Newman and Kenworthy. Their arguments are related to wealth, climate, space, age, health and social problems.

Cyclists ride down Ren’ai Road in Taipei City for Carfree Day

There is a belief that says “The more money you have, the more cars you own.” It seems to be logical, yet they did not find a strong correlation between the increase of live standard and a car-based society. In fact, they discovered, in some cases, the opposite. In regards to climate they found that there is no link between the temperature and the consumption of gasoline, in their study of 32 cities. This finding remains contrary to the argument that warmer cities have a preference to the car because of the diverse activities available outdoors.

Roads must cater to all modes of transportation

These and more examples can be read in their research and they have discovered that the answer is not simple, there is no one explanation. The issues are complex and include a sum of explanations that are rooted in cultural, social, and planning implications.

Picnic in the street at Sunday Streets San Francisco

When I think about it, it is obvious we have to change the ways we plan our cities. Thankfully, it is happening little by little. Our frequency of travel and diverse experiences reveal that every case has its own reasons and therefore the measures must be different in each example. An accurate study to increase the success rate of these actions must be conducted. It is clear that public spaces and roads must be multi-functional and cater to all modes of transportation. In turn, this will provoke the feeling of being part of a community, an interest in taking care of it and standing up to achieve the common good.

It is going to be a lengthy process, but little actions can do wonders. We encourage you to be part of this movement not only on September 22^nd, but the rest of the year. Empower your neighbours and your local governments to take action in order to improve our cities.

From Keys to Sneakers- Pedestrianised Landscapes Embracing The People

Ever since the wheel was invented, it has taken precedence over foot traffic.

Wheeled vehicles—particularly motorized ones—rule the road and shape our public spaces. In fact, when you think of the word city, what comes to mind?

Traffic. Traffic jams. And lots of people. 
For the most part, our cities have evolved into a snarl of vehicles, jockeying bumper to bumper and competing with swarms of sidewalk hoppers.

We could blame it on a number of factors, from the spread of suburbia to the scarcity of public transportation. But no matter how we look at it, one battle will always surface: man vs. machine. Urban designers are becoming increasingly aware of the difficulties of trying to reconcile pedestrians with traffic. Many cities are developing methods to remove heavy traffic from their centers and instead present those spaces as points of accessibility and human interaction.

Perhaps it’s time we re-invented the wheel.

Walk down the Strøget by Kenny Louie

Copenhagen, Denmark, is one city that has made a switch toward becoming pedestrian friendly.   Beginning in 1962, city officials shifted the focus from an optimized vehicular flow and implemented pedestrian initiatives, with the ultimate goal of creating a balance between traffic areas and pedestrian thoroughfares. While many cities experience booming growth followed by the polarization of vehicle traffic and traffic-on-foot, the foresight of Copenhagen’s city planners rescued it from a similar fate.

By 1996, Copenhagen had six times the amount of car-free space than it had when pedestrian initiatives began in 1962.

Today, approximately 37 percent of the people who work in the city use bicycles as their mode of transportation.  In more than 100 locations, bicycles may be borrowed for a cost of around $2.50 and returned when no longer needed–for a refund. Bicycle lanes were added and traffic speeds reduced to promote a more human-friendly city. Many of Copenhagen’s streets were converted into pedestrian-only areas that have encouraged citizens and tourists to park their cars.

Bjarke Ingels Group’s Superkilen

With fewer vehicles on the streets, large parking areas were converted into relaxing public squares, increasing the city’s charm. Copenhagen now boasts more than 100,000 square meters dedicated to pedestrians.Overall, the emphasis placed on pedestrians in the early 1960s has given Copenhagen a head start in the emerging focus on accessibility and human scale in contemporary city designs.

The City Bike system, introduced in 1995, allows anyone to borrow a bike from stands around the city for small coin deposit.

But is it possible to have a car-free city? To many, that’s an oxymoron; but not to the citizens of Louvain-la-Neuve, Belgium, situated 30 km southeast of Brussels, in the French-speaking part of the country. Due to an emergency relocation caused by a language dispute during the 1960s, the Université Catholique de Louvain (UCL) bought a 9-km-square plot on the Lauzelle plateau, a somewhat isolated stretch of fields and woods. But how would they go about creating their new center?  The inspiration for the university-city came down to two men–Michel Woitrin, general trustee of UCL, and Professor Raymond Lemaire, specialist in ancient cities. With the desire for a fresh outlook, they set down nine planning principles to aid in the new city’s construction.

Université Catholique de Louvain

• A custom-made city
• A pedestrian city (diameter of the city is less than 2.5 km)
• Urban center with a human face
• Urban atmosphere, with a town center, from the beginning
• The site is the city matrix
• A well-defined entity in the landscape
• The university is the engine of the city
• The university is integrated in the city
• Flexible design

Guided by these principles, the design began to take shape. The heart of the city is built on a 7-hectare, 39-cm thick concrete slab. It is on this concrete slab, which covers public roads, parking lots, and a train station, that the buildings were constructed. So while access to the city is simple, the traffic is eliminated. Ever heard the expression “you can’t have your cake and eat it too”? They can.  Louvain-la-Neuve is now a thriving, growing city with the loudest noises not caused by street traffic, but by the boisterous hum of people mingling in pubs and shops dotted along the cobblestone streets. For the approximately 30,000 people in and around Louvain-la-Neuve, tossing out their car keys and lacing up their sneakers is an everyday experience.

Bjarke Ingels Group’s Superkilen

But, you may argue, vehicles have opened up the world to us. Economically, culturally–in fact, in almost every aspect–our species’ mobility has created global awareness. There is no denying the fact that the advancement of our technology has provided us with the comforts of today. There is also no denying the fact that to continue on this single-minded tunnel to success will ultimately plunder and destroy the progress that has been made. We’re already paying the price for this fever of energy consumption and push for vehicular accessibility in our increasingly desperate attempts to locate fossil fuels and, more seriously, in our misguided mentality that we can’t live without motorized transportation.

The World’s longest Pedestrian Street -”Strøget”, established in 1962, Copenhagen, Denmark

With the noisy, smelly, dirty, hot world safely ignored behind our tinted automatic windows, we cruise through life without really experiencing our humanity. And it’s the norm. To us, a pedestrian-centric city is an anomaly, a really nice idea, but not reality. Not if you want to get things done. But is life all about doing?  Last time I checked, we were still called human beings. So maybe it’s time to embrace the mentality that these forward-thinking cities have presented to us: that the world is not only a place to get the job done, but a place to be.

The Secret to Making Sustainable Cities – Jan Gehl and His 5 Birds

In the 1960s, urban planners began designing cities for cars, as a result of the increase in car ownership, mainly because of the advance of technology-reducing costs and the over-existence of banking credits. The structure of cities had to respond to this increase in traffic. This meant creating more capacity for parking, building new highways, and increasing the lanes on the streets in order to reduce travel time. People on the streets were forgotten; pedestrians started to walk between cars, and the use of bicycles in most major cities became impossible.

The consequences of the “car invasion” for big cities were very serious, making cities more dangerous, grayer, less healthy, and, in the end, less livable.  Jan Gehl is a Danish urban planner and researcher who has worked in many cities, thinking about how we can make them more sustainable, while at the same time developing them for people. Here are some of Gehl’s ideas:

People Cities = Sustainable Cities

Gehl uses the metaphor of “killing two birds with one stone,” but amplifies this to five birds, with livable cities for people the metaphorical “stone” and the birds representing more lively, attractive, safe, sustainable, and healthy cities (it’s a crude image, but functions to show how the idea works). If we achieve these five goals, we’ll start turning cities into more livable places where you meet and see people in the streets.

Gehl’s theory is based on increasing a city’s ease of movement and viability for pedestrians and cyclists by connecting the city with a good public transportation network, provoking less stress, less noise, less pollution and more interaction among people.

Jan Gehl’s Principles of Places for People

Rio + 20 Summit Conference findings

I recently attended the Rio + 20 summit conference: “the Sustainable City; expressions of the 21st century”, where Gehl spoke and used the example of Copenhagen to show his ideas and theories. Since 1962, the city of Copenhagen has been making its main streets more pedestrian friendly, resulting in an amazing 2 to 3 percent reduction in parking per year. Such actions were effective because the authorities listened to the people on the street. They started to use the model of two sidewalks, two bike lanes and two two-way car lanes.

The results from Copenhagen’s success:

• 37 percent of people use bikes
• 27 percent of people use cars
• 33 percent of people use public transportation
• 5 percent of people walk

The success has been amazing, and these ideas have been emulated in numerous cities all over the world, including Melbourne and New York, with similar results. How can we take these ideas and implement them in the cities of developing countries like México City or Rio de Janeiro?

The success has been amazing and these ideas have been emulated in numerous cities all over the world, like Melbourne and New York, with similar results. How can we take these ideas and implement them in the cities of developing countries like México City or Rio de Janeiro?

Activists paint guerrilla bike lane in Mexico

In many cases, disused train tracks in urban areas are often converted into bike lanes (such as in Mexico’s Federal District a number of years ago).  As such practices gained popularity, doubts arose because most of the bike lanes were in marginal neighborhoods and many didn’t implement a security plan. In the end, it turned out that almost no one used such bike lanes because of the danger, unlike in Copenhagen, where it is probably easier to get struck by a lightning than to be robbed on the streets.

How Rio de Janeiro solved their planning woe

In Rio de Janeiro, we face a very similar problem: It’s one of the most beautiful cities in the world, known as “A cidade maravilhosa”, and it’s perfect to walk through and to find some places for relaxing or to contemplate the landscape, but creating little spots to sit and to gather people together often creates hot spots for pickpockets, and having bike lanes through the city’s tunnels is just the way to enter into the wolf’s mouth.

As citizens of these cities, we can see that municipalities are not doing the research needed and they are implementing many measures without exploring society’s needs. In Rio, we find a city projected for the foreign visitors and not for the Cariocas (native inhabitants of the city of Rio de Janeiro), letting small elements of change inside the city to appease the voters, and in México City just to create impressive numbers to show off in international conferences to keep the budget for urban projects, without doing the research to relieve all the problems that Defeños (people from Mexico City’s Federal District) have to face every day.

Famous yellow tram going up the hill in the Santa Teresa neighborhood in Rio de Janeiro

We are learning and experimenting; nobody knows the correct answer, but we can see that the same mistake is being made: Projects from different places were copied without thinking about the place that would receive them, because of the success they achieved in the first city. We must take into account the environmental, cultural, political, and social characteristics of each place to understand the problems; the differences between them are crucial to generate better cities for people. That’s why I like the idea of Gehl’s birds: He crosses a lot of variables to resolve the problems and thinks in the long term, not in a political period (from four to six years), listening to the people who live in the cities, the actual citizens — the ones who will ultimately be affected by such measures.

Visual Permeability Pavilion

We’ve been saying a few attempts lately at creating unique and creative urban seating. This is yet another example, unique in its own way. This organic piece focuses on minimizing personal space and encouraging socializing.





The wood is organized in three densities, the densest part is used for walking, medium density for reclining and the last is for shading.


Design/Fabrication Team: Luis Alarcon,Aaron Berman,Michael Georgopoulos,Eun Ki Kang,Dayeon Kim,Nicole Kotsis,Jeeun Grace Lee,Aaron Mark,Hylee Oh,Steven Sanchez

America Could End Homelessness in One Year by Doing This

http://www.youtube.com/watch?feature=player_embedded&v=LPxXH7rCSHQ

If America really cared about solving the problem of homelessness among it’s citizenry, here’s an idea that would work. Oh- and that opening line references the fact that as far back as 2011 empty houses in America outnumbered homeless families by five times, according to Amnesty International.

Anyway, let’s say the problem with homeless people in America was a result of not enough housing. Then, this idea would work.


Did you know that you can make houses out of plastic bottles? By filling them with sand, and molding them together with mud or cement, the walls created are actually bullet proof, fire proof, and will maintain an comfortable indoor temperature of 64 degrees in the summer time.




And it’s not like there is any shortage on used plastic bottles out there. Here are some statistics from treehugger.com:


“The United States uses 129.6 Million plastic bottles per day which is 47.3 Billion plastic bottles per year. About 80% of those plastic bottles end up in a landfill!”

To build a two bedroom, 1200 square foot home, it takes about 14,000 bottles.

The United States throws away enough plastic bottles to build 9257 of these 2 bedroom houses per day! That’s just over 3.35 million homes, the same number of homeless people in America.


Many people in third world countries have taken up building homes out of plastic bottles, from Africa to Asia. Perhaps the trend will catch on in America and all of those bottles will stop ending up in the landfills. Wouldn’t they be better off housing the homeless? Kinda like all those empty houses scattered all over the country?


Follow The Free Patriot contributor and Iraq War veteran Kevin E Lake on Facebook.


Source: freepatriot.org

Can You Hear Me? Optimizing Learning through Sustainable Acoustic Design

Architects, engineers and researchers are learning more about how sound waves influence the learning environment and the design of schools for 21st century children and adults. This article will review some of the principles behind the acoustic properties necessary for great learning environments. The professional will review new high-performance acoustic materials, including "active acoustics" - the newest technology for the manipulation of sound in space. These new materials include lightweight gypsum wallboards dimensionally similar to a typical 5/8" drywall, but with superior acoustic absorption. In addition, this article will discuss new high-performance perforated wood veneer and metal panels that can satisfy any sustainable design checklist.

ACTIVE ACOUSTICS AND RIGHT- SIZING PERFORMANCE SPACES

"In general no one acoustic design is perfect for all performance types. Different modes of communication, whether it is speech or music, require the design of a different reverberation time. For speech intelligibility, a low reverberation time is required; for unamplified singing or instrumental music, long reverberation designs are necessary," says Roger Schwenke, Ph.D., architectural acoustics expert at Meyer Sound Laboratories, Inc. Rooms with high ceilings, large cubic volume and hard, heavy surfaces are needed for musical performances. For classrooms, where good speech intelligibility is important, rooms can be smaller and be made of lightweight absorptive surfaces. Because the physical volume and surface treatment are so different, these spaces are mutually exclusive and may require schools and colleges to invest in multiple performance spaces, as well as large classrooms, with limited usability over the school year.

One 21st century approach to acoustics is to design a flexible space that can meet the requirements of all types of performances, from classroom to concert hall. This perfect space can be constructed to optimize all of these performances through active acoustic systems, providing the listener as well as the performer with good sound quality. As schools slash budgets, new technology provides a means to reduce the building footprint in order to combine large spaces into smaller, more flexible lecture and performance spaces without losing acoustic viability.

BIM-driven manufacturing reduced the cost of this ceiling's visually interesting relief design. Openings for sprinklers were precision cut in the factory to simplify field installation and create a clean look. The aluminum and maple veneer system gives the dramatic look of a substantial wood ceiling, but is very lightweight and provides easy accessibility to the area above. University of Southern California School of Law Café, Los Angeles, California Architect: Gensler

The components

To design the room with an active acoustic system, professionals should specify, as a base configuration, a room volume sized for speech intelligibility. This room should have the recommended absorptive materials for low reverberation times even for low frequencies. Active acoustic systems can add reverberation electronically, tuning the sound in the room to meet the additional requirements for hearing music or other types of performances.

They can also increase speech intelligence by providing voice lift and create an "electronic orchestra shell" for listeners as well as for musicians to hear themselves on stage. These systems can be installed to be invisible to the eye, and they can be embedded in perforated walls or ceilings.

Active acoustic systems incorporate the following components:

• Microphones in the room to pick up direct sound near a performer
• Microphones in the audience to pick up existing reverberation
• Loudspeakers that regenerate sound to tune the performance to the required acoustic signal
• Digital signal processors that contain the communications hardware
• Services by trained experts who will locate equipment into existing buildings as well as work with the architect in the early stages of design to provide the minimal room design for performances in new facilities.

An active acoustic system added voice lift to make speech sounds intimate and intelligible during a technical seminar at the Pearson Theatre, Meyer Sound Laboratories, Inc, Berkeley, California. Photo courtesy of Meyer Sound Laboratories, Inc.

Is it green?

According to Roger Schwenke, who is beginning a research study on the possible environmental benefits of active acoustic systems, these systems offer a means to change the acoustics of a room electronically. They are an alternative to physically variable acoustic treatments such as retractable curtains, or doors opening to reverberant chambers. They are green because they provide the alternative to building multiple performance spaces in schools, from K-12 to a university setting. By using active acoustic systems, the cubic volume in a room can be smaller, and therefore the amount of materials needed to construct the building, the energy used in the HVAC and lighting systems are reduced. A lower volume of construction means fewer materials in construction and to transport. Potentially, there is the added benefit of more open space on the site of a shrunken building envelope. Active acoustics can change the sound quality of a room by pushing a button, rather than constructing more square footage.

Zellerbach Hall Acoustic Retrofit

An analysis of this auditorium determined the placement of the components of an effective active acoustic system at Zellerbach Hall, University of California Berkeley. Image courtesy of Meyer Sound Laboratories, Inc.

The 2,014 seat Zellerbach Hall was designed in 1968 as the permanent home and largest indoor venue of Cal Performances, UC Berkeley's premiere music, dance and drama events space. This building won an AIA award for design excellence and it has been the site for numerous performing arts programs including the home of the Berkeley Symphony Orchestra. It was designed for exceptionally diverse programming in the 1960s when architects Vernon DeMars and Donald Harrison had few options for dealing with the diverse acoustic demands of these performance types. Variable acoustics methods involving physical or mechanical means were expensive and electronic enhancement was in its infancy. The architects opted for the only reliable solution available at the time: a "happy medium" wherein the acoustics were acceptable for most of the hall's programs, if optimum for only some. The resulting mid-band reverberation time ended up being 1.45 seconds. This was an ideal length for chamber music, opera and recitals, but at the high end of acceptability for dramatic and spoken-word performances. Music benefiting from a longer and more complex reverberation characteristic, such as orchestral and choral performances, and some types of ethnic and electronic music, was, of necessity, more compromised. They employed a traditional orchestra shell, to add projection and increase the ability of the musicians to properly hear one another, but it was labor- and time- consuming to construct and de-construct for each performance. "We had been grappling with this issue of maximizing the hall's sound for a number of years," says Cal Performances director Robert Cole. "We know the acoustics are quite good as they are; many wonderful artists have performed here with great success. There have been, however, some instances, such as when a period orchestra like Philharmonia Baroque Orchestra performed, when I have wished we could modify the architecture of Zellerbach to better replicate the space in which the music was originally meant to be performed." The challenge presented by Zellerbach Hall was to extend and enrich the venue's excellent physical acoustics while gaining a second acoustical environment similar to that of a classic concert hall. The auditorium also housed graduations and speakers throughout the years, in spite of the challenging acoustical environment. In 2006, the University was approaching its 100-year anniversary and for its gala celebration, they planned to include a wide array of performers from dance to opera. They met with an active acoustics engineering team and Cal Performances, setting three main acoustic goals. The first was to provide an enhanced level of natural-sounding reverberation throughout the hall when desired for selected types of performances. The second goal was to improve projection of sound into the hall, and to allow musicians onstage to clearly hear each other, when the orchestra shell is not in place - essentially by adding a "virtual orchestra shell" as an alternative to the hall's mechanical one. Lastly, the installation needed to be natural sounding as well as not visually obtrusive in this award-winning building. The installation was successful in meeting all of its goals and as Cal Performances music director, Robert Cole, said, "we planned our Centennial Gala comprised of dance, music and a large orchestra and chorus all in one evening. Installing the active acoustics retrofit was the only way we could pull it off."1

A broad range of acoustical characteristics can be provided by active acoustic systems and services. This graph of reverberaton time over frequency shows the range of responses available to Zellerbach Hall, from that of the pure physical acoustics to that with the active acoustics system.

Soundproofing Lightweight Gypsum Meets ANSI School Criteria

To point out the long history of acoustical concern by professionals, Brandon Tinianov, CTO of Serious Materials and current Chair of the Acoustical Society of America's Technical Committee on Architectural Acoustics, quotes Vitruvius: "Sound moves in an endless number of circular rounds, like the innumerably increasing circular waves which appear when a stone is thrown into smooth water." Long after this first- century explanation for sound, professionals continue to examine the complex interactions between architecture and sound waves.

When analyzing the sound transmission of wall components in schools, acoustic experts focus on three main characteristics of sound: level (or sound pressure level), frequency and reverberation. Sound pressure level measures the loudness of a sound, which can be affected by the numerous and complex interactions of sound waves with materials and background noises. The intensity of a sound is measured by the decibel level (dB) and in learning environments, the signal-to-noise ratio of the teacher to background noise is critical. Background noise can be transmitted through the walls from classroom to classroom and from hallways to classrooms. The frequency of sound refers to the pitch or vibration of a sound wave. Reverberation, as defined later in this article, can degrade comprehension of sounds, not just when one or more people are speaking, but also when competing mechanical noises or highway noises disrupt the listener.

Sound pressure level, frequency and reverberation can hurt or benefit speech intelligibility and affect learning. That is why the American National Standard Institute (ANSI) Acoustical Performance Criteria, Design Requirements, and Guidelines for Schools (ANSI S12.60-2002) set maximum standards for reverberation time for different room sizes as well as for Sound Transmission Classifications (STC) and decibel levels for classrooms. ANSI also recommends minimum STC ratings for single or composite wall, floor-ceiling, and roof-ceiling assemblies that separate an enclosed core learning space from an adjacent space. (See ANSI standards in online version of this course.)

Traditionally, professionals specify multiple layers of sheetrock or drywall, or mass to adjoining walls with masonry or staggered studs. All of these solutions add weight, labor and materials to the project. A recent development in lightweight gypsum meets or exceeds the recommended noise attenuation levels for walls while reducing the materials required to achievehigh acoustic performance goals. When compared to other assemblies, soundproofing gypsum drywall provides higher STC values/labor and materials as seen in this 2009 chart using RS Means Building and Construction Cost Data. (See table at end of article.)

Acoustic energy comes in contact with the wall. Constrained layer, damped panel converts acoustic energy to heat energy (in tiny amounts) which is absorbed. Graphic courtesy of Serious Materials

Soundproofing gypsum drywall allows the designer to provide the auditory learning environment as recommended in ANSI/ASA S12.60-2002, as well as meet sustainability design goals. Depending on the wall assembly, and design application, the designer can choose between several types of soundproofing and moisture resistant materials. Although similar to sheetrock, these 5/8 inch drywall panels have a thin innerlayer that adds soundproofing to the wall system without adding the weight of additional layers of wallboard panels. This soundproofing drywall is screwed in place and does not need to have a resilient channel. Gypsum drywall can be perforated by screws without any loss to its soundproofing capacity. This drywall can be specified to be load bearing, or Type X, have a one hour fire-rating, can be specified as abuse-resistant, and can provide an STC 55 rating on single steel stud construction. The materials are as follows:

• For wood construction: a laminated or damped drywall designed for school applications that have a calcium silicate back face.
• For masonry construction: the same drywall as above but placed on one-inch wood furring strips. This application can be used for both interior and exterior walls.
• For metal studs: a gypsum face drywall with magnesium back.

Installation of soundproofing lightweight gypsum used to absorb sound transmission Graphic courtesy of Serious Materials

Sustainability - more acoustic performance with less material

The soundproofing material inside of a 5/8-inch gypsum wallboard is less than one-thirtieth of an inch thick. Lightweight and soundproof, gypsum wallboards deliver soundproofing with many fewer layers of drywall - often less than half of the materials typically used in wall construction - while achieving the same acoustical performance values. Typical soundproofing wall construction used in school projects can use as much as four to six layers of traditional drywall. Other options include the design of walls with double studs to achieve higher performance values. Professionals specifying this product will use less material, less labor and will have less waste on the construction site, as well as gaining additional square footage. With this improved soundproofing technology, professionals can reduce drywall material useage in these situations or applications by up to 75 percent. Moreover, the primary and most sustainable reason to use soundproofing drywall is to enhance human performance and create a "high performance acoustic learning classroom." Soundproofing lightweight gypsum wall boards reduce noise from 70 to 97 percent and can result in STC ratings from 46 to 80 for walls - depending upon the wall assembly

What's next?

According to Brandon Tinianov, CTO of Serious Materials, "One important and overlooked category of acoustical materials is high-performance windows for classroom acoustics." New acoustical windows may be able to achieve sound transmission levels from 35 to 40 STC, STC ratings that are growing closer to wall acoustical performances. These windows will not look any different to the viewer, they will have the same visible transmission values, but they will be heavier and potentially have a thicker profile. Engineers will manipulate the air space in windows to achieve these greater performance levels.

PERFORATED WOOD VENEER AND METAL PANELS

BIM-driven Manufacturing - Making Custom Designs Affordable

BIM-driven manufacturing now allows competitively priced, mass customization of ceilings and interior walls panels. One progressive manufacturer, for example, creates three dimensional building information models (BIM) of ceiling or wall designs, then transfers the geometric data into automated punching machines that trim aluminum or wood-veneered sheets into any size and shape, with tolerances as close as 0.005-inch. After punching, panels are fed through automated machinery that curve panels and form the bends at panel edges. The newest generation of this computer aided manufacturing process allows designers to use curved surfaces, tessellated geometries, and other complex designs without paying the premium prices formerly associated with custom ceilings or walls. The same machines can make as many as 7,000 unique perforations per minute to give panels the desired appearance and acoustical properties. Designers can select the size, shape, and spacing of the perforations, and can even use the perforations like pixels to create patterns, logos, wayfinding cues, and other graphic images. Recent process improvements have made it possible to specify micro-perforations that are almost invisible when viewed at standard ceiling heights yet still afford high noise reduction properties. Larger perforations can be illuminated from above to create luminous ceilings. Ceilings increasingly require careful integration with light fixtures, fire sprinklers, HVAC louvers and grilles, and other building services. Required penetrations for these services are located in the BIM and then formed in the factory to simplify field installation, reduce job site waste, and assure that services are optimally located to maintain the overall good looks of the ceiling.

New types of metal and wood ceiling and interior wall panel systems offer cost-effective alternatives with fresh aesthetic options, outstanding acoustical control, and impressive environmental benefits. Nancy Mercolino, President of Ceilings Plus, a ceiling producer, comments that "the 24 x 48-inch ceiling grid is no longer a given in contemporary architecture. Metal and wood panels now allow designers the freedom to use almost any panel size and shape, plus an increased range of finishes and acoustical options, without breaking the budget."
She explains that perforated metal has been used acoustically for about a hundred years. Yet the appearance and functionality of the products have changed dramatically in the past few years in response to evolving architectural needs and new fabricating technologies. For example, she points out, perforated panels can now be made with recycled aluminum sheets that weighs less than most other ceiling materials yet eliminates most of the oil-canning and visual distortions that used to limit the size of metal panels.
Another breakthrough has been the recent development of ways to laminate wood veneers to aluminum. In the past, Mercolino says, "wood panels were heavy, expensive, combustible, prone to warp with changes in humidity, and offered limited acoustical control. The new laminated products avoid all these problems, making wood ceilings and walls attractive from both the economic and aesthetic vantage." Wood, she suggests, adds a visual warmth and excitement that can soften the institutional feel of a school.
Perforated metal and wood panel systems can also contribute to the sustainability goals espoused by schools. In addition to controlling noise to create better learning environments, the panels have zero-VOC finishes and no added urea-formaldehyde, are durable, contain high recycled material content, do not support mold or mildew, have Class 1 surface burning characteristics, and provide outstanding life cycle value. They are available with finishes that have high light reflectance values to reduce energy consumption and optimize daylighting. And the panels are easily removable for access above a ceiling or inside a wall to commission and maintain HVAC, power and communication cables, and other building systems.

Los Angeles Harbor College - Technology Instruction and Classroom Building

This "smart classroom" is a high-end conference space/auditorium that supports the college TV studio. The room is used for lectures and presentations, as well as for sending and receiving classroom content and live television broadcasts to and from remote locations. Mark McVey, LEED AP, Design Principal at SmithGroup, explains that the acoustic considerations in this room were unique because the space is used for different purposes. "As a TV studio, the room should be dead, without any echo," he says. "But as a lecture space, it should be live enough to bounce the speaker's voice off the surfaces without too much amplification." The designers were able to achieve satisfactory results for both uses by installing perforated acoustic panels with fiberglass backing yielding an NRC (noise reduction coefficient) of 0.85. Because of the need for the raised projectors and projection screen, there is a one-story portion and a two-story portion of the room. Since the designer knew there would be some echoing or problematic acoustics up in the higher portion, he decided to use acoustic ceiling panels. Then, when he discovered that metal panels could be made with a radius, McVey and his team decided to continue the rounded shape down throughout the lower area as well. "It was a design opportunity that came out of the properties of the material," he says. The panel perforations are oblong. This was chosen for both acoustic and aesthetic reasons. "We needed a lot of porosity in the panel to get the acoustic benefits that were required," says McVey, "We thought that using standard circular perforation patterns would result in so many holes, and we wanted to be able to see as much of the material as possible." The aluminum was pre-finished before fabrication with a copper-toned paint that was chosen to give a warm look. Another ceiling achievement in this project was the designers' ability to incorporate a series of components in the room as flush elements, including mechanical registers, speakers, sprinklers, lighting, and projectors concealed behind perforated surfaces or in slots within the ceiling system.

This smart classroom in the new Technology Instruction and Classroom Building achieves both acoustic control and dramatic visual impact with the help of custom curved, perforated aluminum ceiling and wall panels that yield an NRC of .85.

Perforated panels and acoustical performance

One of the leaders in setting performance values for school construction is the Collaborative for High Performance Schools (CHPS).² This organization has developed a report card that parents and professionals can use to rate their schools. How satisfied are parents with the acoustics in their child's classroom? How disruptive are the potential noise sources in the room? Is the mechanical equipment too loud? Can you hear sounds from neighboring classrooms? Does noise penetrate from the outdoors? CHPS sets minimum performance values for good classroom acoustics so teachers can speak without straining their voices and students can hear and effectively communicate to enhance their learning experience.
The CHPS Report Card provides a table of acoustical standards that includes capping ambient noise levels at 45 dBA and limiting the maximum unoccupied Reverberation Time to 0.6 seconds.³ The USGBC LEED® for Schools, Environmental Quality Prerequisite 3: Minimum Acoustical Performance requires that the professional design classrooms meet the reverberation time requirements of ANSI S12.60-2002. According to the American National Standard Institute (ANSI) Acoustical Performance Criteria, Design Requirements, and Guidelines for Schools (ANSI S12.60-2002) a background level less than 35 dBA is preferred for superior acoustics, particularly for young children and those with hearing impairments.
Long reverberation times reduce speech intelligibility in a classroom and it is here that perforated panels are most useful to the designer. Reverberation Time (RT60) is a measure of how quickly, in seconds, sound reflections in a room decay 60 dB or become inaudible. Rooms designed for good speech intelligibility should generally have shorter reverberation times. Reverberation time is typically controlled by the judicial application of ceiling and wall finishes that have higher noise reduction coefficients (NRC).
Noise reduction coefficient (NRC) is a measure of how well a product absorbs sound. Simply put, higher NRC values mean better sound absorption. By selecting ceiling and wall finishes with higher NRC values, the architect and acoustical consultant can control the reverberation time in spaces that require good speech intelligibility. Even without acoustic absorptive materials added, wood and metal perforated panels can have an NRC of 0.40. Add a paper-thin, non-woven acoustical fabric and the NRC can reach as high as 0.75 with as little as six inches of airspace above the ceiling panel. With reconstituted cotton batts that can have up to 85 percent pre-consumer recycled content, the NRC can be 0.95 - an almost perfectly absorptive material.

The artful combination of wood and metal panels vertical and slope surfaces was used throughout the corridors and public areas of this athletic facility to visually unify the building. The warmth of the wood softens the effect of the hard concrete masonry walls. Where required, panels were perforated to yield a high acoustical value of NRC=0.90. Photo courtesy of Ceilings Plus Tompkins Cortland Community College, Dryden, New York Architect: JMZ Architects and Planners, P.C.

NRC values this high are difficult to obtain with conventional wood panels that are made with ½ to ¾ inch thick particleboard cores. Creating perforations in such panels requires drilling - a slow and expensive process that allows only a limited range of hole sizes. More, the thickness of the cores make it physically difficult for sound waves to pass through small holes to reach the noise absorbing materials on the back side. The new types of wood panels, however, made with aluminum cores, are easy to perforate and are so thin that noise readily passes through even tiny perforations.
In school auditoriums and theaters, metal and wood ceilings can be shaped to create good sound diffusion with curved and angled panels. Some panels can be perforated to absorb sound and others can be non-perforated to reflect sound. Perforated wall and ceiling panels can be specified to "tune" the acoustics in a room. By adjusting the hole size, hole spacing, and cavity depth, panels can be designed to absorb more sound at a particular group of frequencies, much like adjusting the bass, mid, and treble controls on your home stereo.
The artful combination of wood and metal panels on vertical and sloped surfaces, was used throughout the corridors and public areas of this athletic facility to visually unify the building. The warmth of the wood softens the effect of the hard concrete masonry walls. Where required, panels were perforated to yield a high acoustical value of NRC=0.90.
Perforated panels can also be used to create acoustically transparent surfaces that allow speakers and electro-acoustic systems to be installed above the ceiling or behind wall panels, reducing visual clutter. In many instances there are already noise-reducing materials above the ceiling in the fireproofing, thermal insulation, or even the air space that will allow noise to be dissipated above the ceiling. More, acoustically transparent surfaces can be used to create longer reverberation time, a requirement in auditoria designed for symphonic music, by adding the space above a ceiling to the acoustical volume of a room.

Materials matter - recycling and FSC-certified wood

Aluminum panels can be specified to contain up to 85 percent recycled aluminum, including as much as 75 percent post-consumer recycled content - usually from beverage cans. Aluminum is one of the most readily recyclable materials and can be recycled repeatedly without loss of strength or metallurgic value. In addition, the steel suspension systems used to support panels can have between 25 percent and 30 percent recycled material content. Professionals can also specify acoustical insulation that is made from recycled cotton; the batts are factory-installed to reduce time and labor costs on the job site.
These panels are light weight systems, are easy to handle, and can reduce a building's deadload. Lighter panels also reduce the shipping impact on a construction budget. For large projects, panel manufacturing can be set up near the project site to increase the regional material content and further reduce the environmental impact of shipping.


Wood veneers that are certified by the Forest Stewardship can be laminated to aluminum cores to create a more sustainable panel configuration. FSC certifies that products do not come from illegal logging and are produced by companies that meet strict environmental and social welfare guidelines.⁴The USGBC LEED® for Schools, Materials and Resources Credit: 7 Certified Wood (FSC) can be applied to only wood certified by FSC, giving this ceiling choice an added advantage for designers. Wood and metal perforated panels can contribute to many LEED® credits - commissioning, local and regional materials, and recycled content.⁵
Additional environmental benefits include the durability of these products; unlike mineral fiber acoustical panels, metal and wood perforated panels are easy to clean, resist damage, and can even be repainted during remodeling without loss of noise reduction value. Factory applied paint finishes release zero VOCs and provide color consistency throughout the entire project. Manufacturers use pre-painted coil before fabricating that gives greater color consistency and a tough more durable finish. Since aluminum is corrosion and humidity resistant, panels can be used above swimming pools, in laboratories and outdoors.

The ceilings and soffits in the Kelley Engineering Center were designed for optimal acoustic performance, and used FSC-certified wood veneers to add natural beauty to the space. This building received a LEED Gold rating. Photo courtesy of Ceilings Plus Oregon State University, Corvallis, Oregon Architect: Yost Grube Hall Architecture

Common sense panel mechanisms and designs

Poor ceiling configurations, tight ceiling cavities, the location of lighting and HVAC ductwork - all of these make the renovation or maintenance of existing buildings difficult. New ceiling panels are designed to swing down from the ceiling plane to expose the systems above for mechanical repairs or replacements. The ceiling panels have torsion springs that hold the panels tightly in place yet allow easy removal for access anywhere above the ceiling.
Alternatively, new panel systems allow metal and wood panels to be installed in standard ceiling grids, an option that is especially suitable for budget conscious projects or when remodeling a space with an existing ceiling grid. Panels can be installed with an exposed tee, a tegular reveal, or a narrow reveal for a concealed tee appearance.
Either way, ventilation louvers, lighting fixtures, sprinkler heads, speakers, and other building services should be integrated into the design of the ceiling system to eliminate clutter.

Designing outside of the box - new design vocabularies

The ceiling plane is typically the most visible surface area in a school room, providing a clean slate where designers can make a statement. While Cartesian grids of square and rectangular ceiling panels may have sufficed in another age, they are no longer emblematic of today's more nuanced pedagogical thinking. Instead, BIM-driven fabrication allows each panel to be unique and for designers to create installations with multiple layers of pattern. For example, triangular, rhombic, or other polygonal panels can create a basic module. Then, by varying joint spacing, individual panels can be clustered into segments that read at a larger scale. Perforation patterns can be varied to define areas within a space, or used as graphics that can extend across the boundary of individual panels to add additional visual texture. Finally, designs can also incorporate multiple panel colors or finishes, and create visual rhythm by the way lights and other fixtures are interspersed throughout a ceiling.
In schools, educators are challenged to expand the minds of their students, to expose them to new ways of thinking. The student is asked to explore new ideas and integrate information toward new actions. In this context, new materials provide an opportunity for learning. Mass-customizable wood veneer and aluminum ceiling and wall panels pose an opportunity for architects who can choose to inspire students and teachers by exploring and integrating this new acoustical design vocabulary on the ceilings and walls of their school buildings.


In response to ADA lawsuits that identified acoustics as a restriction for learning and driven by research that defined the learning thresholds, particularly for children as well as those with hearing disabilities, the Acoustical Society of America (ASA) convened a working group to create acoustic design standards for optimal learning environments. This collaborative effort resulted in the 2002 "American National Standard Institute (ANSI) Acoustical Performance Criteria, Design Requirements, and Guidelines for Schools - ANSI S12.60-2002." This voluntary standard was re-affirmed in May of 2009 and documents stringent standards that will ensure the best auditory enviroment, particularly for children.
The committee included members from specialties in engineering, architecture, bio-acoustics, noise, signal processing and speech communication to name just a few of the specialities represented in this broad consensus effort. The result was an affirmation that "good acoustical qualities are essential in classrooms and other learning spaces in which speech communication is an important part of the learning process. Excessive background noise or reverberation in such spaces interferes with speech communication and thus presents an acoustical barrier to learning. With good classroom acoustics, learning is easier, deeper, more sustained and less fatiguing."⁶
Up to 60 percent of all teaching occurs through communication through spoken language and learning depends on speech perception. Up to 15 percent of all children are estimated to have a slight hearing loss.⁷ The standard focuses on criteria for speech intelligibility in background noise and in reverberant environments in classroom studies. Research cited by this committee included studies in classrooms that linked scholastic achievement including test scores with the auditory learning environment.⁸
The committee recommended a 35 dBA acoustical performance criteria for steady classroom background noise levels assuming that the signal-to-noise ratio of at least +15 dB. In this instance, the signal to noise ratio (SNR) compares the level of intelligigible speech to the level of background noise and that can include everything in a classroom from sound traveling across partitions, to the hum of mechanical equipment, and to the sound of a classroom projector. The higher the SNR ratio the easier it is to hear and to understand the instructor.
When the standard was released in 2002, many professionals found that they were hard to accomplish in a typical classroom with mechanical systems and equipment designed to older acoustic standards. 35 dBA is quiet, so quiet that many schools were not designed to meet this standard.

CHPS, LEED® AND THE FUTURE

The goal of the Collaborative High Performance (CHPS) program a leader in setting school performance criteria is "to improve student performance and educational experience by building the best schools." In the latest CHPS Operations Report Card draft public review materials, they set the criteria for acceptable acoustical background noise at less than or equal to 35 dBA.⁹ However, higher values are listed as acceptable for sound insulation classroom to classrom and classroom to hallway.
Recommended reverberation times range from less than or equal to 0.6 sec in classrooms smaller than 10,000 cu.ft. to 0.7 sec in larger rooms. These recommendations are similar to the acoustic standards recommended by ANSI, which is beginning to be a mandated code in some states.
Manufacturers are continuing to develop new sound attenuating materials for the classroom to assure the best learning environments as documented by the ANSI S12.60-2002 standards. New materials and new technologies will allow designers to take command of customizing the design process, while engineering better environments for speech intelligibility. They will design places for expanded listening and learning.

Advantages of sound damping drywall: Lower cost, additional sellable floor space, improved performance and field reliability over traditional methods Source: RSMeans Building Construction Cost Data, 66th Annual Edition 2008, for volume purchases 1 STC values provided are based on testing according to the ASTM standard E-90 at accredited laboratories * Using a materials factor of 112 (112% of national average) and a labor factor of 138 Chart courtesy of Serious Materials.

ENDNOTES

1 http://www.meyersound.com/pdf/brochures/cs_zellerbach_b.pdf 2 http://www.chps.net/dev/Drupal/node 3 http://www.chps.net/content/044/CHPS_ORC_Public_Review_1_Materials.pdf 4 http://www.fsc.org/399.html 5 http://continuingeducation.construction.com/article.php?L=61&C=322&P=14 6 American National Standard (ANSI) Acoustical Performance Criteria, Design Requirements, and Guidelines for Schools ANSI S12.60-2002. 7 http://www.chps.net/dev/Drupal/node/120 8 A. L. Bronzaft, ‘‘The effect of a noise abatement program on reading ability'', J. Environmental Psychology, 1, 215-222 (1982). J.S. Lukas, ‘‘Noise, classroom behavior and third and sixth grade reading achievement'', Proceedings, 17th International Congress of Acoustics, Rome, Italy, (Sept. 2-7 2001). D.J. and MacKenzie, D.J and S. Airey, ‘‘Classroom acoustics, a research project'', Heroit-Watt Univ., Edinburgh, U.K. (1999). 9 http://www.chps.net/content/044/CHPS_ORC_Public_Review_1_Materials.pdf