January 12, 2005

Lighting can be the key to reviving old neighborhoods

Redevelopment of this rundown area in Copenhagen included new lighting that makes evening activity feel safer and more desirable.

To appreciate the importance of light, particularly in an outdoor space, it's important to understand why people use the space.

Jan Gehl, professor of urban design at the School of Architecture in Copenhagen and chairman of the Urban Design Center, spent time with our sustainable tour group last October discussing research on what makes urban centers vibrant places.

According to Professor Gehl, there are three historical uses for cities: places for people to meet, a market for goods and services, and places to make connections or gain access. He sorted public places into three categories: meeting places, recreation areas and spaces for watching people.

Cities went out of balance when cars were introduced. Cars pushed out people and pedestrian spaces, diminishing the opportunity to make connections.

As cities revive their "people places" by recreating plazas, pedestrian streets, and neighborhood cafes, there are daytime and nighttime components to consider. What makes an area that is vibrant during the day also vibrant at night?

One example of how light can revitalize a community is the district of Holmbladsgade in Copenhagen. During a recent redevelopment of the once rundown neighborhood, one goal was to introduce elements that made evening activity feel safer and more desirable.

This district has high density housing that is uniformly organized off of a main thoroughfare, with wider streets than the historic areas of Copenhagen. Holmbladsgade has retail activity at the street level, with some apartments above. Most of the residential units are on side streets. Prior to the redevelopment, it was considered a less than desirable place to live.

With input from residents, most of the redevelopment funding was put into lighting improvements and public art, with water as a central theme. Although this neighborhood does not have water as a local element, the city is surrounded by water and there was a desire to figuratively bring water into the neighborhood.

General lighting along the main street was improved by replacing high-pressure sodium fixtures with metal halide fixtures. High-pressure sodium yields a yellowish light that makes all colors look dull and brownish, while metal halide is a white light with improved color rendering characteristics.

As is common in many cities in Europe, the street lighting is suspended between buildings on a centenary system rather than the 30-foot poles typically found in U.S. cities. Eliminating poles along the street reduces visual clutter and improves vistas.

On the main street, lighting fixtures allow for a small amount of light to come out of the sides of the fixtures, casting a soft glow. This suggests a higher level of activity and prevents a sharp cut-off of light on the building facades. On the side streets which intersect Holmbladsgade at 90 degrees, a similar fixture and lamp are used but the fixture is a full cut-off fixture. This may have been done because the streets are narrower and quieter, with more residences facing onto them.

Some side streets have plazas with unique lighting, creating places for neighborhood gatherings. On a block that has more historic buildings, all traditional forms of light were replaced with uplights that are installed somewhat randomly near building facades to highlight the buildings. This gives the impression of a much quieter street, with many nooks and crannies to explore.

Street names are identified with placards on the buildings at each corner. These placards are illuminated with a wall-mounted fixture that has a downlight to illuminate the sign, and an uplight contained by the curved upper reflector of the fixture. They illuminate the signs and are also markers to help define the neighborhood.

The main street features two art light pieces that evoke the water theme. One is a grouping of glass tiles with wavy lines of bronze across the top that are clustered at several corners. The glass is illuminated from below with blue LEDs. Each glass tile replaces one cobblestone.

The second piece is a tall, mostly translucent icon with horizontal metal details representing the intersecting side streets of the neighborhood. These are "to scale" and the wavy vertical edge represents the shoreline. They produce a warm white light, and make interesting and distinct markers at intersections. In the summer, they change to a cooler white light. Every half hour they turn blue, a nod to the action of waves lapping onto the shore. They have a full range RGB color-changing system so they can be programmed for any number of unique changes.

Some people would argue that this is not sustainable design because it doesn't use full-cut off fixtures and some of the light goes up into the sky. However, I would argue that this is entirely appropriate for an urban area. The change to metal halide makes colors visible and casts a friendly light. People are easy to see and colors are visually accurate. The street lighting fixture provides a comfortable balance between the necessary working light and a soft glow (not to be confused with glare) emanating from the fixtures to signal life, vitality and spirit for the neighborhood.

The whimsy of the blue glass tiles and the color-changing light of the iconic posts creates surprise, which leads to joy, which makes people want to inhabit the streets. Isn't giving new life to a rundown neighborhood what sustainability is really all about?