The process of lighting a room used to be simple. You bought a lightbulb for a few cents and screwed it into a socket. If a room needed more light, you brought in a couple of lamps and plugged them wherever there was an available electrical outlet and furniture to put them on.

But these days, with so much buzz about conserving energy and saving dollars with light choices, home owners need to shop wisely when they pick lightbulbs — “lamps” in industry lingo. But they can also make their houses brighter, fresher looking, larger, and more attractive to themselves and potential buyers with their choice of lamps, the right wattage or lumens, and the best possible fixtures.

Here’s what they — and you — should know.

What type of light does a room need to meet its needs?

Every room should have multiple layers of lighting that come from three categories, since one usually isn’t sufficient. Every room should have:

▪ Ambient or general lighting that illuminates the entire room.

▪ Task lighting that casts illumination on a specific area to perform a chore — such as chopping vegetables or applying makeup.

▪ Accent lighting to create a feeling like romance at night in a dining room.

How is this combination best achieved?

By using a mix of fixtures, which can vary depending on the room and how much brightness is desired. In general, overlighting rooms but including dimmers to alter the mood and provide for different tasks works best, says Josh Weiss, president of Tech Lighting and LBL Lighting in Chicago. (Note: One type of lighting, the compact fluorescent lamp, usually isn’t dimmable.)

Dimming also helps conserve energy, says Melanie Taylor, a lighting designer and senior associate at the engineering firm WSP Flack + Kurtz in Seattle. In a kitchen where several activities are going on, the task lighting should be three times the level of the room’s general light and might come in the form of undercabinet lights, says Nancy Goldstein, a designer with Light Positive in Marblehead, Mass.

Any extra tips for sellers?

Sellers should play up a few positive features in a room, such as a gorgeous island kitchen countertop, by suspending attractive decorative pendants above it or hanging a pair of sconces in a foyer or powder room, says Kay Green, whose Orlando, Fla., firm stages models for builders. Karen Long, owner of Hinsdale Lighting in Hinsdale, Ill., advises sellers never to remove good fixtures and put up inexpensive replacements. “Better to exclude any they don’t want to sell,” she says. And Weiss recommends getting rid of cheap or antiquated fixtures. “If home owners have really old track lighting with massive heads, which makes the lighting look dated, I would replace that with something like a monorail system,” he says.

What about the type of lamps or bulbs?

Changes happen frequently in the industry due to the need to improve energy efficiency. (Lighting accounts for about 12 percent of a typical home’s energy bill.) Families can also save money — from $50 to more than $100 a year — by changing their bulbs, according to information on the American Lighting Association’s Web site. The three most energy-efficient bulbs are:

▪ Halogen incandescents, which use less energy than traditional incandescents and last longer. They’re good for tasks such as reading.

▪ Compact fluorescent lamps, which are more efficient than standard incandescents, last longer, and are good for hard-working kitchens, bathrooms, and laundry rooms.

▪ Light-emitting diodes, which are the longest-lasting but most expensive. They’re excellent for undercabinet lighting, task lighting, and outdoor steps. An LED light could cost as much as $20 versus $1 for an incandescent, Weiss says.

When buying, home owners should know that labels now emphasize lumens—the amount of light that is produced — over watts, which indicate how much energy is used. A 60-watt incandescent equals 800 lumens, for example. The Federal Trade Commission has worked with manufacturers to develop a new label that helps consumers purchase energy-saving bulbs by listing brightness in lumens, estimated yearly energy cost, bulb life-expectancy, light appearance, and energy used, according to ALA.

Home owners should also consider a light’s color — cool or warm white, for instance — and the choice should depend on the light’s purpose and where it’s placed, says Sal Ferrara, owner of The Electrical Training Center in Copake, N.Y. Color temperature is measured in kelvins; a 3,000-kelvin light has more yellow, for example. And they also might want to know the color rendering index, or how accurately a lamp reflects the right color.

Where should lights be placed?

Location is important to achieve the full effect, and should be determined before rooms are painted or patched and once furniture layouts are planned. For instance, Lang advises hiring a lighting expert or designer to help determine the right height for a chandelier, which is based on a room’s size and height and how it’s used.

What about automated control systems?

These days home owners can program a room for different light scenes. “A home owner might want bright light when they cook but less light when they eat,” Goldstein says. Costs reflect a big range, depending on a home’s size and how many lighting loads or controls systems are included, she says. With some systems, you don’t have to rip up a wall and can program “scenes” from a phone.

Where does a home owner begin?

A house should have a minimum of 100 amps — a fuse box should be updated to that level if it’s not there already, Ferrara says. Also, home owners should hire a lighting design expert for a consultation. Some charge an hourly or project fee, but others can be free if merchandise is purchased. If you don’t know of a firm or expert to recommend, help your clients look for one on the American Lighting Association’s Web site. While there, they can request a copy of its free Lighting magazine. Because many showrooms display a fraction of their offerings, they should always ask to see manufacturers’ catalogs, Weiss says.

Where do old bulbs go?

Whether they’ve gone bad, are outdated, or aren’t sufficiently energy-efficient, they need to be disposed of properly. That means they won’t end up in a landfill, says Brian Brundage, CEO of Intercon Solutions in Chicago. “Take them to a facility that can recycle them properly, often a big-box store,” he explains.