Austin: the bustling Texas city where great music, mouth-watering BBQ, old school cowboys and new school investment bankers mix to create a unique urban environment and experience. Across from Republic Square Park and a short walk from the Texas State Capitol and the heart of downtown, the city skyline is reflected in the two-story glass curtain wall of the new Austin Federal Courthouse.
The ‘Right to Light’ is an awesome piece of legislation in the UK. Unfortunately, it doesn’t exist in the US, and references to it have even been shot down in court cases. The UK law, in layman’s terms, says that an existing property has the right to enjoy and benefit from natural light. So, if a developer comes along and wants to build a bigger building near your property, one that reduces the amount of light your property receives, then they can’t build what they’re planning to. There’s often compromise, but the law ultimately favors people’s rights to natural light. Now, quantifying how much light one is entitled to may get a little more complicated in a legal dispute, but the principle is good – and surprisingly straightforward.
As energy codes continue to evolve, though (and I should note that the ‘Right to Light’ is a zoning law), they seem to be getting more and more complicated. Some code language has become so complex that there’s a concerted effort to simplify it, for better or worse. In principle, I would agree that simplification is in the design community’s best interest, but we shouldn’t set ourselves back just because the math gets too hard. Code language should be as simple as possible, but no simpler.
When considering daylighting and the individual’s right to light, how can we ensure that everyone in a building gets a piece of that daylight? Currently we do no such thing. We simply say, through energy codes, that if you have any daylight in a building, irrespective of building size or proportion, then you need to provide lighting controls to take advantage of the potential energy savings. When we discuss putting daylighting requirements into codes, any language that doesn’t deal with energy is basically forbidden. There’s no home in the current code structure for anything relating to quality. It’s good that we’re at least conscious of one of the benefits that daylighting provides, but perhaps we’re ignoring the most important reason for daylighting a building: we ignore the human factor.
If you wanted to build the most energy-efficient structure possible, you would build a box without windows. Glass is a worse insulator than a solid wall; it lets heat enter into and escape from the building envelope. Historically, we had very large windows because they provided the sole means of lighting the spaces within – great for lighting, but bad for heating and cooling. So, once we developed cheap electric lighting, we did away with all that glass (reference most buildings built in the 1970s). Sure, energy use went down, but so did happiness. I personally went to a middle school where you had no idea what the weather was doing outside until you left at the end of the day, and I certainly would not want to spend hours on end there now. So if no glass is the most efficient, why did we start adding windows again? People’s comfort!
There have been numerous studies over the years, and a little common sense, that told us we went too far in the 1970s. Have we done enough yet, though? If people’s happiness is the real reason for introducing daylight into a building, why do some people still sit near the core of a building, with no windows in sight? Why are buildings even designed to have such spaces? If we are willing to sacrifice energy efficiency to make people happier, why do we only do a half-assed job of providing daylight and views for everyone? Social inequality? Perhaps. LEED does a great job of promoting daylighting and views as an indoor environmental quality issue, but it’s still optional, as is the whole rating system. Maybe it’s finally time to focus on what daylighting our buildings is really about and put it into code language – simple code language.
Is it possible, then, to establish a personal right to light, and does it have any other benefits? Think about it: if we need to provide access to daylight and views for every regularly occupied space in a building, our buildings will naturally get thinner, which begets natural ventilation as well as more useful daylighting. We’ll also be able to seriously re-work our interior space planning so that there are no poor souls trapped behind the solid wall of private perimeter offices. Storage rooms and transient spaces get pushed in, and occupied space spreads outward. Ultimately, the more we can rely on naturally available resources like daylight, the more sustainable a structure becomes.
A building without windows will never be able to be inhabited without energy. Can we say, then, that every individual in a building, in their main workspace, must have access to daylight and views? From a code-language point of view, does this approach help to simplify how we regulate the use of daylighting? It’s a personal ‘right to light’ that just might help us save energy and drive future sustainable design innovation. Is it really that simple and intuitive?
Photo Credits: Paul Sableman (1), Miles Gehm (2), Joel Bedford (3)
Architects were the first lighting designers, and the first daylighting experts. The sun was once the only thing we had to illuminate the interiors of our architecture. We understood its character, its movement, its color and changeability. Until about seventy years ago or so, daylighting was still the primary source of energy used for illumination.
Sure, we had candles, gas lanterns, and finally electric incandescent sources, but it wasn’t until the confluence of air conditioning and the fluorescent tube that we stopped designing our architecture to receive air and light from the great outdoors. Technology has given us wonderful inventions that make our lives on earth easier, happier, more comfortable, and more productive – but for a price. The energy needed to power all of this technology is being depleted. We can heat, cool, and light our buildings in any climate, in any architectural style, but only as long as we have enough fuel.
Indigenous or vernacular architecture was born from solving programmatic needs, using whatever natural resources were immediately available. With the advent of air conditioning in early 1900 and the invention of the fluorescent tube in 1938, we could virtually turn our backs to the outside world and create environments inside our buildings to our liking. As a result, we saw our architecture dramatically change. Office blocks became very large and, consequently, the resulting interior spaces were further removed from the perimeters of buildings. Interior spaces were almost entirely illuminated by electric lighting. It was easier and more economical to use fluorescent lighting than to design a building with more perimeter space that got its light from the sun.
As the years rolled on, we started to realize that these environments were not as desirable as the ones created by nature. Studies started revealing that productivity was suffering, that students’ test scores were in decline, and that people’s health was being sacrificed – all based on a separation from the sun, which helped us to produce vitamin D, set our circadian rhythms, and provided balance to our physical and psychological well-being.
It’s not all a doom-and-gloom story however. Fluorescent lighting is still, by far, the most popular way of illuminating the interiors of our buildings, but with new technologies it is even more efficient than ever before. Furthermore, fluorescence plays well with daylighting. Instead of replacing it, fluorescent and daylight coexist in very efficient and comfortable ways through advanced control technologies and thoughtful design. Dimmable ballasts, photocells, vacancy sensors, individually addressable equipment, and proper design techniques all make it easy to save energy and create wonderful luminous interior environments.
In addition, technology gives us design tools and simulation programs that allow us to forecast energy savings and previsualize our designs in unprecedented ways.
But, in order to take full advantage of these available technologies, architects must reclaim daylighting in their design domain. Unfortunately, the history of architecture in the last century is tragically described as a continual delamination between art and science, because architects passed these technologies into the hands of specialist consultants.
Reyner Banham, in his book The Architecture of the Well-Tempered Environment writes: “… the idea that architecture belongs in one place and technology in another is comparatively new in history, and its effect on architecture, which should be the most complete of the arts of mankind, has been crippling… the art of architecture became increasingly divorced from the practice of making and operating buildings.”
Today the profession is filled with competent and useful consultants and specialists, but the architect must use them, just as technology itself, in a manner that supports the art, and the human being living within that art. We must learn from history, but also embrace technology in ways we’ve never done before, to create beautifully daylit architecture, completely integrated to produce a true balance between art and science.
Photo Credits: Prasad Kholkute (1), Lam Partners (2-4)
The reason for daylighting in buildings is to save energy, and so the value (“payback”) of that daylighting can be calculated by predicting and pricing the amount of energy saved. That’s a common line of thought which is easy to slip into, but it’s dead wrong.
Let’s look at a simple example of a new office building. A typical office worker’s space, including adjoining corridor, is about 110 square feet. Under today’s codes, we’re allowed 100 watts maximum to light that space. If it’s lighted 10 hours per day, 5 days per week, 52 weeks per year, that lighting will use 260 kilowatt-hours per year. At a high-end cost of $0.20 per kWh, that’s 52 bucks for electricity to light that space for a year. Let’s add another 30% for extra cooling cost due to that electricity, and we’ve got almost 68 bucks.
If our worker is the median American clerical worker, according to the US Bureau of Labor Statistics, his salary rate is about $14.40 per hour. Throw in 25% for statutory fringe benefits, and he’s costing his employer 18 bucks per hour.
So let’s say we have a wonderful daylighting design which uses absolutely no electricity to light our worker’s space. That 68 bucks per year equals less than four hours of his salary. That’s right: four hours.
If we have a wonderful daylighting design which improves their productivity by 1%, that saves their employer 375 dollars per year. A productivity improvement of just 1% creates a “payback” five-and-a-half times greater than the value of saving all of their lighting electricity. Run those numbers for a more highly-paid professional, legal, or scientific worker, and the productivity value will be much higher still.
To put it another way, if we calculate the payback of daylighting based only on electricity, we’re grossly underestimating the real payback; we’re shortchanging the daylighting. And that will lead to incorrect design decisions.
Some sophisticated building owners and managers know this. Savvy retailers know that their sales will go up with daylighting. Knowledgeable educators realize that the performance of students in daylighted classrooms will improve. Daylighting produces known health benefits.
We tend to think of these benefits as intangible, but they actually represent large numbers of tangible dollars on the bottom line. Like productivity, these factors aren’t intangible, they’re just hard to quantify.
By the way, the same calculation applies to good electric lighting as well: it may save a few dollars in electricity each year, but its value is vastly greater than that.
Photo Credit: ©Anton Grassl/Esto