The building was constructed a few years ago to act as both a Headquarters and to be a display of what the product they manufacture can accomplish when put to work. The architecture of the building was based around the sun, seeing as AstroPower is a top manufacturer of Solar Power Cells. It involves the glass curtain wall around the exterior, letting light in during working hours, along with many vaulted atrium-like spaces with skylights at the top. This report will describe the existing lighting conditions in the building, specifically in the five spaces that will be used for redesigning. It will examine whether or not the existing lighting conditions satisfy the appropriate design criteria (IESNA) for the space, and comply with energy standards (ASHRAE/IESNA Standard 90.1-1999). This report will also discuss factors of the building that affect the design of each lighting system, such as materials used, material reflectance levels, light loss factors, and others. Part Ia Existing Lighting Conditions General Building Conditions: The uses several different lighting types throughout the twostory office complex. In most of the building, a common 2 x 4 fluorescent troffer is placed in between 2 x 2 suspended acoustical ceiling tiles. Other fluorescent downlights are featured in hallways and vaulted areas, but due to the openness of the floor plan and atrium style skylights, a complex and visually stimulating lighting system was avoided so the light source would be focused on the sun. An example of the fluorescent downlights and the common troffers can be seen in the picture above. Page 2 of 23
Large Work Space Open Office 280 This open office space consists of a total of twenty-four hexagon-shaped cubicles. The cubicles function as small offices for the individuals that are seated there. Most of the cubicles feature a desk, chair, computer, and filing cabinets. The space itself has a glass curtain wall facing the east, and a series of balconies to the left that look down to the first floor, and up to a glass skylight. There is an abundance of natural light in this space, despite the fact of the use of partitions (A plan view of this space is featured in the appendix of this report). The lighting concept that is used over top of the cubicles is a series of 66 2 x 4 3-tube recessed fluorescent light fixtures with 18 cell parabolic lenses, manufactured by Columbia. The fixture utilizes 32-watt T8 fluorescent bulbs with a Standard High Frequency electronic ballast. There is also one 2 x 2 recessed fluorescent light fixture with nine cell parabolic lenses, also by Columbia. This fixture is used simply because of a curved outer wall prohibits the use of consistent 2 x 4 fixtures. It uses a U-Shaped T8 fluorescent bulb with a Standard High Frequency electronic ballast. The walkway next to the area that is open from below features a series of Recessed Fluorescent downlights, with white trim and baffle manufactured by Columbia, using a 26-watt triple tube compact fluorescent lamp with a Standard High Frequency ballast. Page 3 of 23
Special Purpose Space # 1 Lunch Room 133 The Lunch Room is basically a cafeteria style room with small tables and chairs arranged throughout. The tables are to be used for people eating their lunches, having coffee breaks, or maybe even working on a few unresolved work issues. The space features a glass curtain wall on its south side along with being adjacent to the atrium-style Lobby, being separated only by glass panels (which can be seen in the picture to the left) that let light pour in from the skylights above. There is a metal grid that is dropped a couple feet below ceiling height by ceiling suspended pendant fixtures to give the room an added architectural element ( A plan view of this spaced is featured in the appendix of this report). The space consists of a combination of troffers and recessed downlights. There is twenty-three 2 x 2 recessed fluorescent light fixture with nine cell parabolic lenses. There is also ten recessed fluorescent downlights with white trim. They use a 26-watt triple tube compact fluorescent lamp with a Standard High Frequency ballast. Special Purpose Space # 2 Conference Room 191 The Conference Room is mirrored across the Lobby from the Lunch Room on ground level. The center table is used for people holding meetings and gatherings. The space features the curved glass curtain wall on the east side, with two entranceways on the west side. The glass curtain wall allows for natural sunlight to pour into the room. There is a recessed AV screen on the north wall. The space consists of a combination of recessed downlights and special ordered ceiling pendant light fixtures. There are a total of twenty-five recessed fluorescent downlights with white trim and baffle. They use a 26-watt triple tube compact fluorescent lamp with a Standard Page 4 of 23
High Frequency ballast. Two specially ordered ceiling pendant light fixtures hang over the table. The ceiling is trayed in the center to create a nice architectural effect. Circulation Space Lobby The Lobby is one of the most impressive spaces in the building. With its two story ceiling height, open balconies, and overhead skylights. It is used primarily as a place to enter the building, but can be used as a space to hold large functions, gatherings, or presentations. The space features a large glass curtain wall for the entranceway, and when combined with the overhead skylights, the space is filled with natural light. There are a total of twelve 32-watt T8 fluorescent strip lights with Standard High Frequency electronic ballasts that are mounted in between glass partitions that separate the lobby from adjoining spaces (A plan can be viewed in the appendix of this report). There are a total of ten recessed fluorescent downlights on the lower level, forty-one circling the upper balcony, and seventy-three around the vaulted dome ceiling level next to the skylight. Manufactured by Prescolite with white trim and baffle, they use a 26-watt triple tube compact fluorescent lamp with a Standard High Frequency ballast. Around the skylight, are specially ordered wall mounted light fixtures. They provide illumination for the vaulted ceiling, and indirect lighting for the two stories below. They are made with two 32-watt T8 fluorescent bulbs, and use a Standard High Frequency ballast. Page 5 of 23
Outdoor Space Front Entranceway The Front Entranceway is what people pay attention to most when visiting a building for the first time. With this in mind, they made it visually pleasing as well as practical. There are three recessed fluorescent downlights, there is nothing else on the exterior. The parking lot runs almost right up to the building, so there is no place for path lighting. The downlights feature a metallic finish to blend with the building exterior glass, and use the same 26-watt triple tube fluorescent bulb that is used in the fixtures indoors. A plan for the entranceway is featured in the appendix of this report. Page 6 of 23
Part I.b Existing Lighting Hardware Details Ballasts For the fixtures used in the, all fluorescent bulbs were used to make the building Green. The Standard High Frequency ballast was used for both the recessed downlights and the troffer fixtures. The input voltage is to be 120 to 277 volts, with an input frequency of 60 Hz. Ballasts must be physically interchangeable with a magnetic core and coil ballast. The ballast must have permanently connected leads integral to the ballast, color coded to ANSI C82.11. It must be formed from recyclable steel painted in accordance with UL 935 standards. Plastic products with gaseous discharges are not allowed. The ballast factor is 0.75 0.78, and must be able to start and operate the specified lamps at a minimum temperature of -20 degrees Fahrenheit and be sound rated A. The THD shall be less than 20% for the main lamp design, and the Lamp Current Crest Factor shall not exceed 1.7. The Power Factor must be greater than 98%. The ballasts must also be CSA approved and UL listed (Class P). Lamps The fluorescent 32-watt T8 bulbs should have a color temperature of 3500 degrees Kelvin with a color rerndering index of 85. The fluorescent 26-watt triple tube bulbs should have a color temperature of 3500 degrees Kelvin, a color rendering index of 85, and emits 1100 lumens. Luminaires The 2 x 4 fluorescent troffer is the J24-3 model manufactured by Columbia Lighting. All metal parts are processed with a five phase phosphate bonding treatment. Grid units are prepainted with high gloss baked white enamel, 86% reflective. The shielding is 100% acrylic prismatic, extruded and roll-embossed, with diagonally oriented female prisms. Page 7 of 23
The 2 x 2 fluorescent troffer is the J22-2 model manufactured by Columbia Lighting. All metal parts are processed with a five phase phosphate bonding treatment. Grid units are prepainted with high gloss baked enamel, 86% reflective. The shielding is 100% acrylic prismatic, extruded and roll-embossed, with diagonally oriented female prisms. The recessed fluorescent downlight is the CFCB_TH Compact Fluorescent Downlight manufactured by Prescolite Architektur. It has the white American Matte trim and a 360 degree rotatable Virtual Source cross baffle with upper reflector. It is housed in a one-piece painted 18- gauge cold rolled steel platform, with a pre-wired J-box with snap on cover for easy access. The fixtures in the conference room were privately designed. They have a reflectance level of 85%, and are made of steel. Daylight Daylight, as mentioned before, is prevalent in the building design. Every space that has a wall along the front glass curtain wall sees daylight from sun rise to sun set. The openness of the Lobby and Open Office work areas allows light from the multiple skylights to reach most rooms in the building. Glass The appearance of the glass on the curtain wall appears green in color and has a sandblasted texture to it. Transmittance information for this material is important for factoring in the Luminance and Illuminance in the specific rooms; however an assumption must be made due to the fact that they were custom made and the information has not yet been received. The projected amount of transmittance through a sandblasted glass material will be 70% to 85%. The clear glass used in the skylights will be said to have a transmittance level of 90%. Page 8 of 23
Reflectances Reflectance values in the five spaces that will be redesigned should be carefully considered. The reflectance values of the surface material used in the room will affect how much light will be reflected back and in the end will affect the lighting design in general. In the Open Office area, the partitions have a reflectance value of 50%, the desk surface is matte and has a reflectance of 45%, the Video Display Terminals reflect down onto the surface. The walls are painted off white and have a reflectance value of 65%. The floors have a reflectance value of 25%. The structural columns have all been painted a color, therefore eliminating any notable reflectance that might come off them. The ceiling is also painted off-white, and has a reflectance level of 85%. The glass curtain wall has a reflectance value of 70% to 85%, but for now we will say 80%. The Lobby has the same ceiling, walls, and glass values as mentioned above. The Lunch Room has the same ceiling, walls, and glass values as mentioned above. The tables and chairs have a semi-gloss finish with a reflectance level of 26%, complying with the 3:1 guideline for the ratio between the luminance of the task and its immediate surroundings. The Conference Room has a dark table, with a reflectance level of 25%. The ceiling, walls, and glass all have the same reflectance values as mentioned above. Page 9 of 23
Part II.a Design Criteria According to the IESNA Lighting Design Guide in the IESNA Handbook (Ninth Edition), the illuminance values and criteria have been recommended for different spaces with different functions. The values recommended are not required, simply a suggested guide to correctly light various types of spaces. Large Work Space Open Office 280 The design criteria for an Open Office space with Intermittent VDT use says that it is important to consider the appearance of space and luminaires. The space is used for people working on desks, being able to see papers, computer screens without glare, and interacting with other people and being able to see their faces clearly. It also says that it is important to consider color appearance and contrast, flicker and strobe, light distribution on surfaces, uniform light distribution on task plane, modeling of faces or objects, shadows, source/task/eye geometry, and surface characteristics. Direct glare is said to be very important in considering the lighting scheme. Daylighting integration and control is said to be only somewhat important. Both illuminance values (horizontal and vertical) are important, with the horizontal illuminance having a recommended value of 50 footcandles, where as the vertical illuminance recommends only 5 footcandles. Special Purpose Space # 1 Lunch Room 133 The design criteria for the Lunch Room fall under the Food Courts section of the IESNA Guide. People in this space should be able to see what they are eating, interact with others and see them clearly without shadows or glare. Items that are said to be very important include appearance of space and luminaires, color appearance and contrast, and daylight integration and control. Areas of design that are said to be important are direct glare, flicker and strobe, light Page 10 of 23
distribution on surfaces, and shadows. Finally, areas that are said to be somewhat important include uniform light distribution on task plane, luminances of room surfaces, modeling of faces or objects, points of interest, reflected glare, source/task/eye geometry, sparkle/desirable reflected highlights, surface characteristics, and system control and flexibility. The horizontal illuminance is said to be important, having a recommended value of 30 footcandles. The vertical illuminance is said to be somewhat important, having a recommended value of 3 footcandles. Special Purpose Space # 2 Conference Room 191 The design criteria for the Conference Room fall under the Conference Room Meeting section of the IESNA Guide. The people who are in this room need to be able to accurately read documents in front of them on the work plane, easily view others sitting across the table without shadows, and sit in a comfortably lit environment for long periods of time. Areas that are important to focus on include appearance of space and luminaires, direct glare, and modeling of faces or objects. Items that are recommended to be of important consideration include color appearance and contrast, light distribution on surface, uniform light distribution on task plane, luminance of room surfaces, and reflected glare. Items said to be of somewhat importance include daylighting integration and control, flicker and strobe, shadows, and source/task/eye geometry. Both the horizontal and vertical illuminances are said to be important. The horizontal illuminance recommends a value of 30 footcandles, whereas the vertical illuminance recommends a value of 5 footcandles. Circulation Space Lobby The design criteria for the Circulation Space fall under the Offices Lounges, Lobbies, and Reception Areas section of the IESNA Guide. The people who are in this space need to see where they are going. Seeing others clearly is not necessarily a necessity, and people here will not often Page 11 of 23
be looking at papers or documents. The only recommendation for very important lighting design is the appearance of space and luminaires. Areas of importance for lighting design include color appearance and contrast, direct glare, light distribution on surfaces, luminances of room surfaces, modeling of faces or objects, and surface characteristics. Somewhat important areas include daylighting integration and control, flicker and strobe, reflected glare, and shadows. The horizontal illuminance is said to be somewhat important, and a value of 10 footcandles is recommended. The vertical illuminances is said to be important, and a value of 3 footcandles. Outdoor Space Front Entranceway The design criteria for the Front Entranceway fall under the Outdoor Section, Building Exteriors, Entrances, Active (pedestrian/conveyance) section of the IESNA Guide. Seeing as how the people that use this entrance will normally be using it during daylight hours, lighting design was probably not high on the list of priorities. However, when darkness falls you need to be able to see where you are going clearly and see other people. You also want to have a comfortable lighting scenario to view. The Guide says that items in lighting design that are very important include appearance of space and luminaires, color appearance and contrast, direct glare, light pollution/trespass, modeling of faces or objects, peripheral detection, points of interest, reflected glare, shadows, source/task/eye geometry, and surface characteristics. Areas that are important are light distribution on surfaces and sparkle/desirable reflected highlights. Both of the illuminances, horizontal and vertical, are recommended to be very important areas to focus on. The horizontal illuminance is 5 footcandles, the vertical illuminances is 3 footcandles. Page 12 of 23
Part II.b Power Allowances According to the ASHRAE/IESNA Standard 90.1-1999, different spaces with their purposes and tasks are given power allowances. From Table 9.3.1.2 Lighting Power Densities Using the Space-by-Space Method the values were determined for the four indoor spaces to be redesigned. For the Outdoor Space, Table 9.3.2 Lighting Power Limits for Building Exteriors was used. Large Work Space Open Office 280 The table concludes that in an Office Open Plan no more than 1.3 watts per foot squared should be utilized in the design of the lighting system. Sufficient lighting is important for this area in order for people to complete their work and view others. Special Purpose Space # 1 Lunch Room 133 The table concludes that in an Office Dining Area no more than 1.4 watts per foot squared should be utilized in the design of the lighting system. Lighting is needed on table surfaces to adequately see what is being served and the people who might be sitting around you. Special Purpose Space # 2 Conference Room 191 The table concludes that in an Office Conference Meeting/Multipurpose room no more than 1.5 watts per foot squared should be utilized in the design of the lighting system. It is important to be able to see documents on the table, as well as other individuals in the room. This is why the power density is a little higher than in the other places. Page 13 of 23
Circulation Space Lobby The table concludes that in an Office Lobby no more than 1.8 watts per foot squared should be utilized in the design of the lighting system. This is due to the fact that the entranceway is what people first see, so a little bit more design is put into make it look as best as it can. This is why the power density is higher in this area. Outdoor Space Front Entranceway The table concludes that in a Building Entrance without canopy the power density should be 33 watts per linear foot of door width. This is to provide adequate lighting so that people can see where they are going and others around them. Page 14 of 23
Part III Evaluation of Existing Lighting Conditions Evaluation of The usage of all fluorescent lamps in energy saving ballasts created a very effective energy saving environment. In combination with the solar power additives from the roof and glass cells, a truly green building was created. The fluorescent color lights blend nicely with the daylight entering through the many windows and skylights. The luminaires also provide a streamlined looking interior, matching the exterior design concept. They also do not take away from the many architectural details on the interior that make it such an interesting building to look at. Evaluation of Large Work Space Open Office 280 The lighting design in the open area provides ample light for the cubicles while providing an aesthetically pleasing environment. The symmetrical design indicates order and structure; A company that works together as a team. Should a client ever take a tour of the office facility they would be pleased to see how the individuals that are working for them can come together and get things done. The design is practical and well thought out. Evaluation of Special Purpose Space # 1 Lunch Room 133 The lighting design of the Lunch Room is well thought out and creative, without using many expensive luminaires. The dramatic iron dropped ceiling adds an interesting architectural element to the room, and contrasts with the curved glass curtain wall that looks outside. It makes the space comfortable to relax and enjoy a break from a busy work day. There is more than enough light to do work, eat, or talk with coworkers. It is an interesting and practical design that Page 15 of 23
allows the space to stand out in a building with many impressive areas. Evaluation of Special Purpose Space # 2 Conference Room 191 The lighting in the Conference Room is both professional and orderly. The custom made luminaires that hang over the table add an interesting design element to a type of room that is normally uninteresting. There are many different lighting schemes that allow for different settings, whether it is a board meeting, slide show presentation, or other type of function. The lighting design is simple and effective. Evaluation of Circulation Space Lobby With light leading all the way up to the atrium style skylight, it feels as if you are still outside even though you are not. The usage of recessed compact fluorescent downlights creates a symmetrical and orderly look, while highlighting interesting architectural designs. In the evening the view from outside is quite impressive, the way the light draws you inside. The lighting design defines the Lobby as the most visually stunning room in the building. Evaluation of Outdoor Space Front Entranceway One of the only areas in (or out of) the building that needs a little extra design is the front entranceway. The only reason it is really noticed at night is because of the Lobby behind it. It should have a design just as good, if not better, than what lies inside. It should draw you directly to it, and the three recessed downlights do not really achieve this. Page 16 of 23