Hartford/Beaver Dam is well known as a community with a good quality of life, small and cohesive neighborhoods. This deserving reputation is due in part to the City’s small size, entrepreneurial spirit, civic-minded citizens and activist government. One of the many factors that makes Hartford/Beaver Dam such a great place to live, work and visit is the community’s attention to detail, and respect for it’s setting, heritage and quality urban design. Hartford/Beaver Dam’s Design Guides strives to protect the city’s unique qualities and strong sense of place by carrying out citywide development and design objectives. The purpose of this Design Guide is to help applicants in preparing projects to be reviewed by the Hartford/Beaver Dam Planning Commission. Through materials such as this, the Hartford/Beaver Dam Joint Planning Commission seeks to make information available well before the final design of a project saving the applicant, and the city, time and money. Lighting can be an important tool, when used carefully, in enhancing the Hartford and Beaver Dam architectural heritage. However, of all the many design issues, outdoor lighting is arguably one of the more difficult to understand and visualize. The first things you need to consider are: What is the purpose of the light? • What kind of light is already around me? • Do I really need to add more outdoor light - will it improve visibility or make my property more secure? • How much light do I really need, and what are the long-term energy costs? LIGHTING CONCEPTS AND ISSUES There are several concepts and issues that you need to understand before adding light to your property. It is the combination of all of these factors that creates a quality lighting application that will benefit you and the community. Illumination Level The level of illumination refers to the amount of light needed for a specific task. Most of us are led to believe that more light is better. However, this is not necessarily true. The light level on a typical sunny day at the beach is 30,000 foot candles and 1,500 on a cloudy day. However, you only need 0.1 foot candles to read the serial number on a dollar bill. Unless you’re planning to do needlepoint, think "less is more." Glare When light shines directly into your eye, visibility is reduced due to glare. Glare causes contrasts to be washed out and harder to see. Causes of glare include using too much light and improperly aimed fixtures. The solution is to use only as much light as you need, direct the light to where it is needed, and shield the lamp from view. Cutoff fixtures are often the best choice. Cutoff fixtures are shielded so that the light is focused exactly where it is needed (one can also use reflectors inside the lamp to aim the light). Finally, the height of the fixture helps define the area that is lit. Surprisingly, it’s better to have more lights at a lower height, than fewer high up. If they’re too high, they will light the area directly around the light, not the area on the ground that needs it. By focusing the light directly onto what you want illuminated, you’re not wasting energy or money and contributing to an over-lit environment. Uniformity & Security While the human eye can adjust to a wide range of light conditions, it can only adapt to one at a time - typically the brightest. This causes everything else to appear very dark in comparison. If your neighbor has a really bright light, your yard by comparison probably feels very dark. This kind of over-lighting is increasingly common, and creates areas that are very bright and very dark. Competing light levels detract from our sense of safety and security, and the overall character of a neighborhood. Personal safety and site security are some of the most common reasons people add light. However, it is the quality of the light, not quantity, that improves our sense of security the most. Energy Efficiency Not all lights are created equal. There are wide ranges in efficiency based on both the amount of light produced per watt, and the life-span of the lamp. Factors which affect energy efficiency include the how much light is used (see Illumination above), the amount of misdirected light (see Glare above) and the color of light desired (see Color below). The bottom line is that no-one wants to spend more than we really need. Color The color of the light used affects how objects appear compared to normal sunlight. The color you choose is often based on two factors - the task and energy usage. Incandescent lamps (your basic light bulb) offers the closest to natural light, yet are a very inefficient user of energy. High pressure sodium (HPS) lamps, while very efficient and long lasting, emit an orange-yellow light that distorts color as well as our ability to identify features at a distance. Metal halide lamps emit a cool white light which makes for more accurate object identification and adds to our sense of security. This white light creates a sky-glow similar to moonlight rather than the orange glow of HPS, and are only slightly less efficient at commonly used wattages. DESIGN OBJECTIVES √√√√√ The lighting level should be appropriate to the task. Remember, less is more! √√√√√ Lighting levels should be reasonably uniform to avoid very bright and very dark areas. √√√√√ The lamp should make objects appear as close to a natural color as possible and provide high energy efficiency. √√√√√ The fixture should minimize glare and spill-over onto adjacent property or into the sky. This can be done through the use of cutoff fixtures and/or reflectors in the lamp. √√√√√ The mounting height of the fixture should be as low as possible. √√√√√ Sensor-controlled lights (typically heat or motion) should be considered for security lighting and for energy savings. (See Article XI, §10,§§ 7 regarding "flashing lights and signs"). √√√√√ If you are proposing lighting on your site, you may need a permit and should include a lighting plan with your application. This should include the proposed fixture style, wattage, location, mounting height, and any existing light fixtures that will be replaced, relocated or remain remember, a flashing light used for the purpose of attracting attention to a business or business related activity, internal or external to a structure, is classified as a sign for the purpose of the ordinance. (See Article XI, §10,§§ 7 regarding "flashing lights and signs"). SOME COMMONLY USED TERMS: Foot candle: A measure of light falling on a surface. One foot candle is equal to the amount of light generated by one candle shining on a square foot surface one foot away (Lux is the metric equivalent of foot candles, and both can be measured by a light meter). Lumen: A measure of light energy emitted by a light source. Luminaire: The complete lighting fixture including the lamp (i.e. bulb), lens (used to direct and distribute light) and the wiring. The luminaire is typically mounted on a pole or other fixed object. Uniformity Ratio: The ratio of average to minimum illumination.
|