Sun Tubes: Skylight Alternatives?

Plus, sun tube cost vs. conventional skylight cost

Dome shaped solar tube skylight on asphalt shingle roof
Steven White / Getty Images

When remodeling your home, it's not uncommon to encounter spaces that lack natural light. Hallways, extra bathrooms, staircases, guest bedrooms, and attic conversions are just a few of the places that tend to be distant from windows, so natural light is at a premium.

So, why not just add a window? In many cases, it's very difficult or impossible to add a window because of attic space or wall orientation. Even a conventional skylight, with its wide, straight light shaft, might be too difficult to incorporate.

A viable alternative might be to install sun tubes. Similar to skylights, sun tubes funnel natural light into spaces, helping you save on energy costs—but without the imposing infrastructure that skylights require.

What Sun Tubes Are

Also called light tubes, solar tubes, sun tunnels, or tubular daylighting devices (TDDs), sun tubes are flexible or rigid metal tubes that start at the roofline and end at a home's ceiling. Sun tubes bring diffused light into a home.

From below, sun tubes look similar to recessed light fixtures in your ceiling. While they don't transmit as much light as a skylight or window, the light they do provide is a significant improvement over electrical lighting, at least during the day. Homeowners can reduce their need for artificial lighting in the home with sun tubes.

How Sun Tubes Work

Sunlight at the roofline is directed through a tube, which can bend or turn as needed. The tube extends from the roof to the ceiling of a space. A diffuser is mounted on the ceiling to distribute the light evenly throughout the room. Even if the sun isn't burning brightly, the sun tube will still transmit plenty of natural light into a room without transmitting heat.

Most sun tubes include some type of device to enhance the natural light. This may be a reflective coating on the inside of the sun tube or a bundle of fiber optics to conduct the light.

If you are handy with tools, you can install the sun tube yourself, which involves climbing on the roof to cut a hole and weatherproofing it. With no light shaft to build from scratch from two-by-fours and drywall, sun tubes are simple to bring from the roofline to the ceiling.

Pros and Cons of Sun Tubes

  • Can bend around obstructions

  • No need to build light shaft

  • Less expensive than skylights

  • Can be installed by capable homeowner

  • Little or no view

  • Less light than skylights

  • Little or no direct natural light

  • No ventilation

Cost of Sun Tubes vs. Conventional Skylights

Sun tubes offer considerable cost savings over installing a skylight or window. They're available in several sizes, ranging from a ten-inch diameter up to 20 or more inches.

Expect to pay around $700 to $2,200 for a 14-inch sun tube. Sun tubes on the lower end of the price range are basic installations: homes with lower roof pitches, less distance between the roofline and the ceiling, and lower ceilings within the home.

Homes that have steeply pitched rooflines, many obstructions between the roof and the ceiling, and a high or angled ceiling will be found at the more expensive end of the scale.

An average-priced conventional skylight with a light shaft starts at around $1,800 and ranges up to $4,800 to $5,000.


You may be eligible for federal, state or local home energy tax credits when you install a sun tube. Check with the sun tube retailer or with your county or state.

Are Sun Tubes Worth It?

For homeowners who expect to stay in their homes for many years, sun tubes can be a worthwhile purchase, at least from the financial angle. The $1,450 per sun tube average cost should be weighed against per-room energy consumption for lighting. It's a steep cost that takes many years to amortize, but long-term homeowners may be able to do so after 20 to 30 years.

From an environmental standpoint, sun tubes are worth it since they reduce or eliminate the need for energy.

From a personal angle, many homeowners may find that sun tubes are worth it because they are able to enjoy more natural light during the day. Natural light elevates moods and helps with productivity.