Like inside the home, exterior lighting should be designed using layers of light. Begin with the ambient or general layer of light for overall illumination. This layer typically uses light sources positioned along pathways, as well as lighting that washes light up and down the walls. Stagger pathway lights 6 to 8 feet apart for just enough light to see while walking and to avoid the "runway effect" that can occur when lights are evenly distributed along the path.
Illuminate stairways with step lights installed into stair risers for safety and as a nice focal point for decks, patios and gardens. Another option is to place tape lighting underneath stair steps to highlight stairways. To wash the house with light, use lighting installed in the soffits of the home's exterior or use a mix of down and up lights to spread light across the entire surface for a balanced look.
When choosing entry lighting, which can serve as outdoor task lighting, the ALA offers these basic guidelines:
Wall sconces placed on either side of the doorway should be one-quarter or one-third the height of the doorway. Position them 66 inches from the floor to the center of the fixture and 6 to 12 inches from the door casing.
Fixtures placed over the doorway should be one-quarter or one-third the width of the door frame and centered 6 inches above the door.
Hanging lights, such as pendants and lanterns, should be one-fifth the height of the door and hang 6 inches above the door.
Select accent lighting to add drama and provide the perfect curb appeal. Light trees with ground lights aimed up into the foliage, while making sure the trunk is also bathed in light. Or place lights high in trees and use a cooler light bulb of about 5,500 Kelvin to give the effect of real moonlight.
Create dramatic focal points by cross-lighting statuary, fountains and architectural elements with two beams of light. In garden beds, place fixtures no closer than 20 feet apart to create pools of light that draw the eye from one area to the next. A good rule of thumb is to use warm (yellow/orange) light on objects and cool (white/blue) light on plants.
Always select outdoor lighting that is wet-rated for places where the lighting receives direct exposure to the elements. Use weatherproof or outdoor-rated electrical boxes that safely hold the electrical wire connections and prevent contact with water.
SOURCE American Lighting Association
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