Dear Jim: My kitchen and a hallway are dark and I would like to add some natural lighting. Skylights are too expensive and I can’t install them myself. Are the lower-cost skylight tube kits a good alternative? – Paul N.

Dear Paul: Installing a skylight tube is an excellent lower-cost alternative to a large skylight. If you are an average do-it-yourselfer, installing one should be well within your skill level or the dealer can install it for you.

When I first learned about skylight tubes, the concept seemed almost too simple to be effective. As a test, I installed one in my garage where I restore cars. My medium-size one lights the entire two-car garage.

Skylight tubes are particularly popular for kitchens because the natural light makes foods look more appetizing than when using artificial light. Also, the full-spectrum of natural sunlight on our eyes is thought to help minimize problems with the blues that some people experience each winter.

A skylight tube is basically a small (10- to 22-inch diameter) tube with a super-reflective interior. It has a clear weatherproof dome on top that extends through the roof and a light diffuser on the bottom that mounts in the room ceiling. The diffuser looks like a standard ceiling light fixture.

The sunlight enters the dome and bounces back and forth off the reflective interior until it shines out the ceiling diffuser. On a sunny day, its free-light output is equivalent to many 100-watt light bulbs. They are so effective that the light from a full moon often creates a glow in the room.

In addition to lower cost and easy installation, a skylight tube is more energy-efficient than a large skylight. With its smaller opening in the ceiling, a skylight tube loses less heat. The dead air space inside the reflective tube creates insulation valve to further reduce energy loss.

There are two basic types of skylight tubes: rigid and flexible. The rigid type is ideal where there are few obstructions between the ceiling and the roof. Elbow sections, with an angled end, allow you to create few bends to miss obstructions. Fewer bends produce more light output though.

If you must wind the tube around more obstructions, choose one with a one-piece flexible tube. You can bend it in any direction, similar to a clothes dryer duct. This is probably the easiest type to install for the beginner.

Venting models that include an exhaust vent fan are ideal for bathrooms, too. For light at night, choose a model with an optional built-in electric light. Models with a prismatic dome capture more light rays in early morning and evening. Snap-on mood diffusers are available to vary the lighting.