Shining a Light on Solar Tubes
These eco-conscious skylights are gaining in popularity for all the right reasons
Solar tubes — also known as sun tubes or tubular skylights — can help illuminate your home in an energy-conscious way. Solar tubes are sturdy columns that penetrate the roof and ceiling to pipe daylight, much like a skylight, into interior rooms. Though they don’t offer the expansive overhead view that traditional skylights do, they minimize solar heat gains and losses much better than skylights. Additionally, their relatively narrow diameter means they’re less intrusive to framing and drywall and are therefore more cost-effective than their rectangular cousins.
Back it up with LED. Since solar tubes work only during the day when the sun is out, you’ll still need a backup light source for evenings. This bathroom complements dual solar tubes with energy-efficient LED fixtures above the vanities.
Pro tip: If possible, position your solar tubes on a southwest-facing roof to capture the most light. However, bear in mind that a straight run of tubing is always best, as twists and turns will deliver less light.
Pro tip: If possible, position your solar tubes on a southwest-facing roof to capture the most light. However, bear in mind that a straight run of tubing is always best, as twists and turns will deliver less light.
Ideal for rooms with limited or no windows. Solar tubes are great for lighting interior hallways that don’t see the light of day. But they can also create what I call a “flashlight effect,” casting shadows around objects below. Nature’s flashlight is better than no light at all, though, and installing solar tubes in long rooms that already have a window on one side can help mitigate the shadows.
Ceiling style can boost your light. Coffers or tray ceilings help concentrate the light by providing additional surface area for it to reflect off of. More reflective surface space helps diffuse the column of light and spread its reach. Generally speaking, a standard 10-to-14-inch light tube will illuminate roughly 300 square feet around it. The reason 10-to-14-inch diameters are common is that they fit snugly between framing members, which are commonly placed 16 inches apart. Wider solar tubes are, of course, available for walls or ceilings with wider framing.
A better shower skylight. Not unlike a window or traditional skylight, solar tubes require a little extra planning for shower applications. Condensation can occur when the air outside is colder than the air inside, so proper ventilation is important for solar tubes mounted in wet areas. In climates that face extreme cold during the winter, it’s advisable to have tubes insulated with foil-wrapped insulation.
The good news is that solar tubes are less prone to leaking than traditional skylights. The smaller exposed surface area helps, but the integral flashing is the real saving grace.
The good news is that solar tubes are less prone to leaking than traditional skylights. The smaller exposed surface area helps, but the integral flashing is the real saving grace.
They pack a powerful punch. The first thing you probably notice about this photo is the way the shower stall glows. Without the solar tube, this picture could scarcely be taken since the room would be so dark. Instead, thanks to a single, small column of light, the shower is as bright as, well, the sun. This is a textbook example of a solar tube solving the illumination problem in a confined space where a tiny bit of light can go a long way.
Hallway highlight. Hallways are another ideal place for tubular skylights. There’s nothing space-age or mod about light tubes; they simply brighten the passage with the highest quality, lowest cost light source around. Generally more affordable than traditional skylights, light tubes will easily pay for themselves both financially and karmically as the electricity meter idles and the Earth smiles.
Nature’s glow. In this living room, an assemblage of six solar tubes are laid out similarly to recessed cans for task lighting. The room benefits from a large window wall toward the front, but the quality and brightness of that light decreases incrementally as you step deeper into the room, making a secondary natural light source desirable. A room with multiple light sources reduces glare by casting light more evenly throughout.
More
How to Add a Skylight or Solar Tube
Going Solar at Home: Solar Panel Basics
More
How to Add a Skylight or Solar Tube
Going Solar at Home: Solar Panel Basics
This before-and-after shot shows an electrically lighted space on the left compared with a sunlit entry.