Windows & Doors Review: Tubular SkylightsTubular skylights brighten rooms with the ultimate renewable energy source.

A product doesn't have to be new for homeowners to consider it state of the art. But if it brightens interior rooms with free natural light and installs in just a couple of hours, even a product that's been around for nearly two decades can seem avant-garde.

That's the reaction that tubular skylights have generated for Aurora, Ill.-based Bigelow Homes at its urban/suburban lofts, apartments meant to look like they're in the city, rather than the suburbs.

"Customers really think [the tubular skylights] are cool," says Mike Venetis, vice president of sales and marketing for the company, which uses cutting-edge design and materials to build energy-efficient production homes. "They think they're high-tech. When they bring their family and friends in, they always brag about them."

That "wow" factor, along with the product's energy-efficiency benefits, is driving word-of-mouth interest in tubular skylights among consumers and builders looking for a non-intrusive way to brighten their homes--even though the day-lighting tubes were first sold in the United States more than 15 years ago.

Tube Specs
Vastly different from traditional skylights, tubular skylights consist of a dome on the roof, constructed with an optical plastic like polycarbonate or acrylic; a metal tube coated with reflective material that can be straight or bent; and a diffuser on the interior ceiling. The dome collects sunlight that bounces down the tube, sending natural daylight to brighten up even inside rooms.

Venetis says tubular skylights' green attributes help set his development apart. "It's a product that's perceived as new technology and energy efficient, so it helps improve the perceived value of the home," he says. "We use Solatubes in areas that we can't otherwise get natural light in, so it gives the overall home a better feel."

Natural light also is better for color rendering, so homeowners no longer need to worry about whether the color of their clothes or the intensity of their makeup looks the same once they leave the house, says Neall Digert, vice president of commercial market development for Solatube. "They can apply makeup with total confidence," he explains.

Solar Savings
Even before the green building trend gained traction, tubular skylights were the definitive solution for energy-efficient lighting. Forget low-wattage incandescent bulbs or fluorescent lights; tubular skylights provide high-quality light for free. "It provides light without the need for electric light with a lot more consistency than windows or skylights," points out Digert.

Traditional skylights can generate unwanted heat, but not so for tube lights. "On a 100-degree or 90-degree day, the shaft can create a tremendous amount of heat," says Stuart Cully, a dealer and independent contractor who owns Sun Pipe of Arkansas, in Hot Springs, Ark. "With ours, you don't get the heat pushing down into the room."

The opposite is true on cold days. With no roof insulation and only a few inches of glass separating cold air from warm, the warmed air in a home will rise and be cooled by a skylight. Miller says that traditional skylights add about $20 in energy costs per square foot of glass each year on a national average. Tubular skylights add less than a dollar to annual energy costs. With the installed cost of a tubular skylight running at about $500 to $550--compared to $1,500 to $2,000 for a traditional skylight--the payback on energy savings is only one to two years.

Other Advantages
Tubular skylights have other advantages over their traditional box-type counterparts. Because traditional skylights are usually at the end of a long shaft, they don't provide much light for a room unless the sun happens to be shining directly through the glass. Tubular skylight domes are formulated to collect even low-angle light and redirect it to the diffuser, which sends light to all corners of a room. At mid-day, the output of a 14-inch skylight can be as strong as five 100-watt light bulbs.

For those reasons, a tubular skylight is really a substitute for an electric light, not a skylight, says Greg Miller, owner of Sun Pipe. "Once you know the product, the only reason you want a skylight is because of the view of the sky," he says.

Manufacturers say the future looks bright for tubular skylights. They shed some light on new trends:

• Light dampeners. With devices to control the output of the diffusers, tubular skylights are moving into the bedroom. Solatube, for instance, offers an optical dimming system with light switch that can dim the output to between 100 percent and 1.5 percent.

• Electric light and fan kits. Designers don't like having separate daylights, electric lights, and vents in the ceiling. New kits allow the diffuser to serve multiple functions.

• Attractive diffusers. Some manufacturers offer paintable trim rings and multiple lens options that look clear, frosted, or like brushed linen, so the diffuser can make a design statement.

• See the clouds. Solatube's Digert says the company's Specialite Infinity reflective tubing, for example, uses 420 micro-fine layers of acrylic to reflect visible light without changing the color, meaning you can see the sky and clouds through a clear diffuser lens.

--BUILDING PRODUCTS

Installation Ideas
Installing a tubular skylight always has been a fairly simple and non-invasive project, especially in comparison to traditional skylights. While adding a skylight can be a two- to three-day messy project, tubular skylights install in about two hours, manufacturers say. "We're making them easier to install and more user-friendly," says Keith Early, marketing manager for the retail division of ODL.

To that end, they've added installation instructions and templates, replaced some of the screws and bolts with flap tabs in the diffuser so installers don't need an extra set of hands, and made the adjustable elbows longer so contractors spend less time in the attic. Velux uses adjustable roof pitch adapters, meaning the tube can run straight from the roof to the ceiling whether the roof is on a 3/12 slope or an 8/12 slope.

--J.L.

DayLite

DayLite. The DLX15 tubular skylight illuminates up to 150 square feet, while the DLX30 illuminates up to 300 square feet. The DLX30 has a 12-inch double dome on the roof, providing complete isolation from external weather conditions. The dome's "fly-eye" lens and lower diffuser lens are multi-faceted prismatic moldings that trap a second layer of air for additional insulation. 888-329-5483. www.dayliteco.com.

ODL

ODL. The tubular skylight's new two-piece installation kit makes installing the skylight simple because the bottom adjustable tube can overlap the top adjustable tube, the maker says. The Solar Lens dome is designed to optimize available sunlight even during low-light hours. During full mid-day sun, a 14-inch tubular skylight has output equal to about five 100-watt light bulbs, according to the manufacturer. 866-635-4968. www.odl.com.

Sun Pipe

Sun Pipe. Tubular skylights are available in 9-inch diameters for 100-square-foot areas and 13-inch diameters for 240-square-foot areas. The product's Super-Flash-300 galvanized steel flashing with rolled seams should outlast the roof and provide a double barrier against leaks, the maker says. The diffuser dome is available with optional trim rings or with clear prism-cut material. 800-844-4786. www.sunpipe.com.

Velux

Velux. Sun Tunnel skylights are available with pitched flashings that gather light from all directions, or low-profile flashings that bend to the roof line. The skylights are also available with flexible tubes that make installation easier, or rigid tubes that provide brighter, whiter light. The one-piece flashing uses corrosion-resistant metal and has a scratch-resistant coating. 800-888-3589. www.veluxusa.com.

Sun-Dome

Sun-Dome. The tubular skylight's high-impact polycarbonate dome blocks harmful UV rays and withstands hail and hurricanes, according to the manufacturer. Adjustable tubes are standard in the 10-inch and 13-inch models to bypass obstacles in the attic. The aluminum flashing can be painted any color and won't rust or leak, the maker says. The skylight can be installed in about two hours, the company adds. 800-596-8414. www.sun-dome.com.

Sun-Tek

Sun-Tek. The Sun-Tek Tube is available in 10-inch sizes to brighten up to 150 square feet, and 14-inch sizes to brighten up to 250 square feet. An optional light kit allows customers to use the tube as an extra light source day or night. All tube sizes include up to 50 inches of tubing, but extension tunnels are available in 20-inch and 34-inch lengths. 407-859-2117. www.sun-tek.com.

Tubular Skylight

Tubular Skylight. The firm's tubular skylights are available in the TSL-64 for compact rooms, the TSL-100 for small rooms like bathrooms, and the TSL-400 for rooms up to 400 square feet. Adjustable four-section elbows allow the tube to be installed anywhere in the home, the manufacturer says, and the Eclipse electric dimming system allows users to toggle the light level. 800-315-8823. www.tubular-skylight.com.

Elite Solar Systems

Elite Solar Systems. The firm's tubular skylights feature a paintable one-piece aluminum flashing; a vacuum-formed, high-impact acrylic dome with UV stabilizers; and a reflective tube made with MiroSilver anodized aluminum with 98 percent reflection. The company offers three types of diffusers as well as an aluminum trim ring. Optional accessories include a bathroom vent, light kit, or manual or wireless electric dimmers. 866-772-5418. www.elitesolarsystems.com.

Solatube

Solatube. The redesigned Brighten Up Daylight System includes the 160 DS, which illuminates up to 200 square feet with a tube diameter of approximately 10 inches, and the 290 DS, illuminating up to 300 square feet with a 14-inch-diameter tube. The new lights are designed to be brighter, with Raybender technology that extends the hour of daylight by collecting and directing low-angle sunlight. 888-765-2882. www.solatube.com.