A skylight is a window installed in the roof instead of a wall. Because it faces the sky, it brings in more daylight than a wall window of the same size, and it can reach rooms that wall windows can't, like interior bathrooms, hallways, and stairwells.
That light comes with a trade-off: every skylight is also an opening in the roof. Installed well, with the right flashing and glass, a skylight is no more likely to leak than any other roof penetration. Installed poorly, it becomes one of the more disruptive problems a roof can develop.
TheRemodelers works with licensed window and roofing contractors to help homeowners understand what each type of skylight does, what it costs to install in 2026, and how to choose the right size, placement, and glass. This guide covers fixed, vented, and tubular skylights, what moves the price up or down, the building code rules for skylight glass, and what to ask a contractor before signing.
Skylight Types at a Glance
Type | How It Works | Opens? | Installed Cost | Best For |
|---|
Tubular (sun tunnel) | A small roof dome captures sunlight and a reflective tube carries it to a ceiling diffuser | No | $600 to $1,400 | Hallways, closets, and bathrooms without windows |
Fixed | A sealed glass unit framed into the roof | No | $1,500 to $3,000 (new opening); $800 to $2,200 (same-size replacement) | Living rooms, kitchens, and vaulted ceilings where maximum light matters |
Manual vented | A hand crank or pole opens the sash | Yes | $2,000 to $4,000 | Kitchens and bathrooms with ceilings you can reach |
Electric or solar vented | A motor opens the sash by remote or wall switch | Yes | $4,500 to $8,500 | High or vaulted ceilings where the skylight is out of reach |
What Is a Skylight?
A skylight is a glazed opening in the roof that lets daylight into the room below. On a typical sloped roof, the skylight sits between the rafters, and a short framed and drywalled light shaft carries the light down to the ceiling. On a vaulted or cathedral ceiling, the skylight sits in the ceiling plane itself, so there is little or no shaft at all.
Three terms come up constantly when shopping, and they are not interchangeable:
Skylight: the general term for a fixed or vented glass unit installed in the roof, usually out of reach overhead.
Roof window: an operable skylight installed within reach, common in attic bedrooms and bonus rooms, where it is opened by hand like a regular window.
Tubular skylight: also called a sun tunnel or tubular daylighting device. Instead of a large glass unit, it uses a small roof dome and a reflective tube to pipe light into a room, with no view through it.
Because a skylight collects light from overhead for more of the day than a wall window does, a single, well-placed unit can noticeably brighten a room that already has windows. That same exposure to the sky is why size, orientation, and glass selection matter so much more for a skylight than for a wall window.
Fixed Skylights
A fixed skylight is a sealed glass unit that does not open. It is the most common full-size skylight and typically costs $1,500 to $3,000 installed when a new roof opening has to be cut and framed, or $800 to $2,200 to replace an existing skylight with a new unit of the same size.
With no moving parts, a fixed skylight has fewer places for air and water to get through, and it delivers the most light for the money among full-size skylights. Most quality units use double-pane glass with a low-E coating and argon fill, which keeps the glass surface warmer in winter and cuts heat gain in summer.
The trade-off is ventilation. A fixed skylight can't release the warm, humid air that collects near the ceiling, which matters in kitchens and bathrooms. It also adds heat gain if it is oversized or faces west into the afternoon sun. For a living room, kitchen, or vaulted great room where light is the goal and the room already has other ventilation, a fixed skylight is usually the right call.
Vented Skylights: Manual, Electric, and Solar
A vented skylight opens to let air out, and it comes in three versions. Manual vented skylights open with a hand crank or a pole and cost $2,000 to $4,000 installed. Electric vented skylights open with a motor and a remote or wall switch, and solar-powered versions run on a small built-in solar panel. Motorized units cost $4,500 to $8,500 installed, and choosing solar over hardwired electric saves about $400 to $800 because no wiring has to be run to the unit.
Venting at the ceiling works because warm air rises. Opening a skylight lets heat and humidity escape from the highest point in the room, which is why vented units are a strong choice in bathrooms, kitchens, and upper floors that run warm in summer. Many motorized models include a rain sensor that closes the skylight automatically when the weather turns.
Vented skylights have more seals and moving parts than fixed units, so build quality and installation matter more. A manual vented unit makes sense when the ceiling is low enough to reach. For a high or vaulted ceiling, a solar or electric unit is the practical option, since a skylight you can't reach is a skylight that never gets opened.
Tubular Skylights (Sun Tunnels)
A tubular skylight is the most affordable option at $600 to $1,400 installed. A small dome on the roof captures sunlight, and a highly reflective tube, typically 10 to 14 inches in diameter, carries it down to a diffuser in the ceiling that looks similar to a light fixture. Because the tube fits between the rafters, there is no structural change to the roof framing, and the roof opening is far smaller than for a full-size skylight.
Tubular skylights are ideal for closets, hallways, laundry rooms, and windowless bathrooms, where the goal is daylight rather than a view. They add very little heat gain or heat loss because of their small glass area. Rigid, highly reflective tubes carry light more efficiently over long runs than flexible tubes, so ask which type a quote includes if the attic run is long.
The limitations are real: a tubular skylight offers no view of the sky, does not ventilate, and brightens a smaller area than a full-size unit. For a room where a view and plenty of light are the point, a fixed or vented skylight is the better investment.
What Drives Skylight Installation Cost
The biggest cost factor is whether the job is a replacement or a new opening. Replacing a skylight with a new unit of the same size reuses the existing rough opening and light shaft. Adding a skylight where none exists means cutting the roof deck, framing a header between the rafters, building and drywalling a light shaft, and finishing the ceiling, so the labor is considerably greater.
Roof material comes next. Asphalt shingle roofs are the simplest to work with, while tile, metal, and slate roofs need specialized flashing kits and more careful handling. Roof pitch and height matter too, since steep or tall roofs require more safety setup. On top of that, glass upgrades, ventilation hardware, and local permit fees all add to the total.
Project Scenario | Typical Cost Impact |
|---|
Same-size replacement of a fixed skylight | $800 to $2,200 installed |
New fixed skylight with a new roof opening | $1,500 to $3,000 installed |
Installing during a full roof replacement | Saves about $800 to $1,500 |
Tile, metal, or slate roof | Adds $500 to $1,000 or more for specialized flashing |
Solar-powered instead of hardwired electric vented unit | Saves about $400 to $800 in wiring |
Timing a skylight with a roof replacement is the single easiest way to save. The roofing crew is already on site, the shingles are already off, and the flashing can be integrated into the new roof as it goes on. If your roof is approaching replacement, it is worth planning skylights into that project rather than cutting into a new roof later. The roofing projects hub covers what goes into a full roof replacement.
Choosing the Right Size, Placement, and Glass
Size. The U.S. Department of Energy's rule of thumb is that skylight area should be no more than 5 percent of the floor area in a room with many windows, and no more than 15 percent in a room with few windows. For a 12-by-15-foot room (180 square feet), that works out to about 9 square feet of skylight in a bright room, or up to about 27 square feet in a dark one. A common 2-by-4-foot skylight is 8 square feet. Going larger than the guideline is the most common reason a skylight makes a room too hot or too bright.
Orientation. A north-facing skylight delivers soft, even light with the least heat gain. East-facing units bring morning light. South- and west-facing skylights collect the most sun and the most heat, which is welcome in a cold climate in winter but can overheat a room in summer without the right glass or a shade.
Glass and code. Building codes treat skylight glass as overhead glazing and require safety glass in it. Under the International Residential Code (Section R308.6), the most common choice is laminated glass on the room side, which holds together if it breaks. Tempered glass is also allowed, but in many installations a tempered room-side pane requires a protective screen below it, which is one reason most residential skylights use laminated inner glass. For energy performance, look for a low-E coating suited to your climate, with a lower solar heat gain rating in hot regions. The guide to window glass options explains how laminated and tempered glass differ.
Room | Recommended Skylight Type | Why |
|---|
Windowless bathroom | Tubular, or manual vented if the ceiling is reachable | Daylight without a large opening; venting helps release moisture |
Kitchen | Fixed or manual vented | Strong task light over counters; venting releases cooking heat |
Vaulted living room or great room | Fixed, or solar or electric vented | Maximum light and view; motorized venting for out-of-reach ceilings |
Hallway, closet, or stairwell | Tubular | Affordable daylight in spaces that rarely have windows |
Attic bedroom or bonus room | Roof window or vented skylight | Fresh air and light in a space that often runs warm |
How to Choose the Right Skylight
Lowest cost: a tubular skylight at $600 to $1,400 brings daylight into small spaces with the smallest roof opening.
Most light and a view of the sky: a fixed skylight, sized to the 5 to 15 percent guideline.
Ventilation: a manual vented skylight where you can reach it, or a solar vented unit where you can't.
Lowest heat gain: a north-facing placement or a tubular skylight, with low-E glass suited to your climate.
Best overall value: install during a roof replacement to save about $800 to $1,500 on labor and flashing.
If you are still deciding between a skylight and other ways to add light, the guide to different types of home windows covers transoms, picture windows, and other light-adding styles.
What to Look for in a Skylight Contractor
Skylight installation sits between two trades, roofing on the outside and interior carpentry and drywall on the inside, so ask how the contractor handles both before signing.
License and insurance: confirm both, especially since the work involves cutting into the roof structure.
Flashing approach: ask whether they use the manufacturer's flashing kit matched to your roof material. Most skylight leaks trace back to installation errors, not product failures, and the roof flashing guide explains why the layering sequence matters.
Permits: a new roof opening usually requires a permit, and the inspection protects you.
Warranties: get both the manufacturer's product warranty and the installer's labor warranty in writing. The guide to window installation warranties explains how the two differ.
Itemized quotes: get at least three, each separating the skylight unit, flashing, light shaft framing, and interior finishing so you can compare them line by line.
Final Thoughts
A skylight is one of the most effective ways to bring natural light into a home, but it is a roof project as much as a window project. Choose the type by the room: tubular for small interior spaces, fixed for maximum light, and vented where heat and humidity need somewhere to go. Size it to the 5 to 15 percent guideline, pick glass suited to your climate, and pay close attention to who installs it, because the flashing determines whether it stays dry for decades.
Before you commit to a design, get a professional set of eyes on your roof and ceiling. Home Upgrade Pros can match you with licensed contractors near you for a free, no-obligation assessment. Reach out online or call (725) 313-0738.
Frequently Asked Questions
What is a skylight?
A skylight is a window installed in the roof instead of a wall, letting daylight into the room below. The three main types are fixed skylights, which do not open; vented skylights, which open manually or with a motor; and tubular skylights, which use a small roof dome and a reflective tube to carry light into a room.
How much does skylight installation cost?
Tubular skylights cost $600 to $1,400 installed. Fixed skylights cost $1,500 to $3,000 for a new roof opening, or $800 to $2,200 for a same-size replacement. Manual vented skylights cost $2,000 to $4,000, and electric or solar vented skylights cost $4,500 to $8,500.
Do skylights leak?
A properly installed skylight with the manufacturer's flashing kit, matched to your roof material, is no more likely to leak than any other roof penetration. Most skylight leaks are caused by installation errors, not by the skylight itself.
Is it cheaper to install a skylight during a roof replacement?
Yes. Installing a skylight during a full roof replacement saves about $800 to $1,500, because the roofing crew is already on site, the shingles are already off, and the flashing can be built into the new roof.
What size skylight do I need?
The U.S. Department of Energy recommends skylight area of no more than 5 percent of the floor area in a room with many windows, and no more than 15 percent in a room with few windows. For a 180-square-foot room, that means about 9 square feet of skylight in a bright room, or up to about 27 square feet in a dark one.
What kind of glass does a skylight need?
Building codes require safety glass in skylights. Laminated glass on the room side is the most common choice because it holds together if it breaks. Tempered glass is also allowed, but in many installations it requires a protective screen below it. For energy performance, choose a low-E coating suited to your climate.
