Home owners tend to spend a lot more time picking out paint colors, furniture and flooring for their homes, new or old, than they do on lighting fixtures and light bulbs. But lighting affects how everything in your home looks. And it affects your mood, productivity, even self-image. Example: You’ll likely face the day with more confidence if your first glimpse of your face in the bathroom mirror is brightly and warmly lit rather than exposed to glare and shadows.

As we get older, indoor lighting is especially important. Aging eyes often struggle to read and work in low light, and they cope poorly with excessive glare. After you’ve maximized natural light—the kind that comes streaming in through your windows and skylights—pay attention to how your home is lit when you draw the blinds and when nighttime falls. 

Five lighting mistakes to avoid…

Mistake: All the lights in a room shine down from above. When the only lighting in a room is from overhead, the room seems emotionally cold and impersonal—the lights can cast harsh shadows on faces and make homes feel like offices or retail spaces.

Solution: Add lighting at head level, and the room will instantly feel homier and more comfortable. What constitutes “head level”? That depends on the room. In spaces where people tend to stand, such as in entryways and hallways and at bathroom counters, sconces mounted approximately five to six feet up the wall work well. Near seating areas in living rooms and family rooms, opt for table or floor lamps that shine light ­approximately from seated head height. 

Mistake: Skipping the sparkle. Nature has three types of lighting. There’s ambient light, the general brightness of the daytime sky…focal light, the direct light of the sun…and sparkle, the glimmering light that reflects from bodies of water. Sparkle is the most beautiful and enchanting. But while all people already have the first two types of light inside their homes (ambient from wall reflection and focal direct from fixtures), most people do not have sparkle in their homes. The glimmering light from sunlight striking water isn’t just pretty to look at, it also stimulates our appetites (a good thing in your dining room) and fosters a sense of well-being. One hypothesis is that we have evolved to associate glimmering light with being safe—sunlight sparkles off water only when the skies are clear and the water is fairly calm. 

Solution: Sparkle is attractive almost anywhere, but it is an especially good lighting addition in dining rooms and kitchen eating areas, where fostering appetite and a sense of well-being encourages great family meals. Sparkle also is good in entranceways, living rooms, family rooms and bedrooms. A crystal chandelier is an effective way to create sparkle, but if that’s too showy for your tastes, any lighting fixture that features faceted glass or a shiny, pebbled metal finish is likely to produce sparkle, too. Caveat: Don’t use sparkly lighting in a home office…it’s too distracting. 

Mistake: Banishing shadows. Many home owners assume that shadowy ­areas are an interior design problem that they need to fix by adding more or brighter lights. That’s not true—shadows can be beneficial. 

Shadows allow us to use light to focus attention where we want it focused, perhaps on the well-lit seating area of a living room or on the piece of art in an otherwise neutral entryway. Shadows create a sense of depth and dimensionality in a room. And they reinforce a comforting sense of privacy—that’s why crowded restaurants and cocktail lounges sometimes feature well-lit tables with shadowy areas in between. 

It’s counterintuitive, but shadowy areas in rooms tend to boost the moods of people who spend time there. We tend to think of shadows as gloomy, but the absence of shadows is more likely to elicit negative moods. Consider: Which kind of day makes you feel more energetic and upbeat—a sunny day of bright light peppered with areas of crisp shadow…or an overcast day where everything is the same even brightness?

Solution: In most homes, it is hallways, family rooms and living rooms that are most likely to be “over fixtured”—these spaces do not need to be brightly lit throughout. In a hallway, we need only enough brightly lit areas to see where we’re going. In a family room or living room, we need bright lighting only in the seating and play areas.

Of course, not all shadows are beneficial. You don’t want shadows on faces where people often sit or stand…or in spots where people cook, read or work. 

Mistake: Visible light bulbs. If you can see the bulb inside a lighting fixture from anywhere in the room where you regularly sit or stand—or even a portion of the bulb—that fixture is creating glare that will detract from your ­enjoyment of the space and your ability to function there. Exceptions: If you can see bulbs through a translucent shade or if they are in recessed fixtures in the ceiling, there likely won’t be glare. 

Glare is not only annoying—it also triggers a disorienting deer-in-the-headlights feeling that makes it hard for us to concentrate or enjoy ourselves. And the older we get, the more sensitive to glare we become. 

Solution: This problem can be solved by switching to a light bulb that is small enough to be completely hidden from view by the fixture. Or you can choose a larger shade…reposition a floor or table lamp…or replace clear glass elements of a fixture with tinted or frosted glass. 

Mistake: Overlooking useful spots for lighting. Some rooms in your home already may appear to have the lighting they need. But adding a new fixture often can solve problems. Examples…

Bedrooms often have focal lights above the head of the bed for reading. But very few have a focal light positioned above the foot of the bed, where suitcases often are packed and laundry sometimes is sorted. 

Bathrooms often lack overhead lights above the shower or tub, where they are very useful for shaving and other grooming. A “wet location” lighting fixture is appropriate here. 

Walk-in closets generally have overhead lights positioned in the center of the ceiling. That not only creates glare if the bulb is uncovered, it leaves items on lower closet shelves hidden in shadow. The ideal spot? Often it’s directly above the inside of the closet door. That’s where people are least likely to look directly at the light, so it cuts down on glare…and it’s where the light will illuminate deepest onto closet shelves along the far wall. 

Kitchens benefit from under-cabinet lights. But when under-cabinet lighting is located at the back and pointing forward, it may shine in your face when you’re seated. Instead, locate lights at the front, pointing toward the back. 

Choosing the Right Bulb

Even the best lighting design can be ruined by poor bulb choices. Here are two common mistakes…

Too-high color temperature. The overall color emitted by a light bulb is described as its “color temperature” and expressed in terms of degrees ­Kelvin (K). If you like the warm tone of a traditional incandescent bulb, choose a bulb (of any kind) with a color temperature of 2700K. If you prefer the whiter tone of a traditional halogen bulb, a Kelvin temperature of 3000K will serve you well. A color temperature above 3000K leans toward blue and will not seem warm and welcoming. Note: Color temperature is particularly important for bulbs where you sleep, such as night-lights and illuminated displays on bedside clocks, because blue light at night tends to disturb our sleep/wake cycle. 

Too low on the “color-rendering index.” The lower a bulb’s color rendering index (CRI), the less accurately colors will appear in its light—reds start to look gray and faces seem sallow. Incandescent or halogen bulbs always have a perfect CRI score of 100. But when buying LED or fluorescent bulbs, choose those with CRIs of 90 or higher. While CRI isn’t always listed on bulb packaging, manufacturers almost always tout on their packaging when bulbs provide 90-plus CRIs. Two bulb makers known for high-CRI bulbs are Hyperikon (recently $18 for a six-pack of 60-watt-equivalent 3000K LED bulbs with a 95 CRI) and Cree (recently $34 for an eight-pack of 40-watt-equivalent 2700K LED bulbs with a “90+” CRI).