Natural lighting has the power to make a home feel brighter, warmer and more inviting. Whether you’re looking to cut down on energy bills, boost your mood, or simply bring a touch of the outdoors inside, sunlight is the ultimate lighting upgrade.
For homeowners looking to add more natural light to their properties, two popular options stand out: skylights and sun tunnels.
In this post, we’ll break down the differences between the two, so that you can select the one that fits your home, your goals, and your budget.
What is a Skylight?
A skylight is a window installed on the roof of your home to let in natural light. Skylights provide expansive views of the sky and can transform dark rooms into bright, open spaces. They’re commonly used in living rooms, kitchens and bathrooms.
Skylights can be vented, meaning they can be opened to allow for airflow. This is especially valuable for rooms like bathrooms, where ventilation is essential to avoid mold growth. Vented skylights can be opened manually, with a remote, or even automatically on the basis of how much sunlight is available.
Alternatively, skylights can be fixed, which means they’re sealed tight, which might make installation and maintenance a bit simpler.
Most skylights use glass, but it’s also possible to use acrylic or polycarbonate designs, which can sometimes be cheaper. If using glass, your skylight can have either a single, double or even a triple pane.
The biggest advantage of skylights over sun tunnels is the amount of light they let in. This can transform a room and open up your living space. The vented variety can bring in air as well as light, making for a really natural home environment.
The downside is that skylights are more expensive and complex to install and maintain. Installation might require a structural modification of your roof. If done incorrectly, this can lead to leaks when it rains. And without proper insulation, skylights will make your room much warmer in the summer and much colder in the winter.
What is a Sun Tunnel?
A sun tunnel is an acrylic dome that captures sunlight from the roof, sends it down an aluminum tube, and diffuses it into the room below. Sun tunnels are smaller, rounder and subtler than traditional skylights, and can send light into rooms where skylights aren’t feasible. Common use cases include hallways and small bathrooms.
There are two types of sun tunnels: rigid and flexible. Rigid sun tunnels are straight tubes that are typically installed at 90 degrees to the roof, and are used if there are no obstacles between the roof and the ceiling. If such obstacles are present, it’s normally smarter to use a flexible sun tunnel to manipulate the light around them.
The main advantage of sun tunnels over skylights is that they can bring sunlight into spaces that don’t have direct roof access. They’re not as flashy or expansive, but they do offer a noticeable lighting boost during the daytime. Since they’re smaller than skylights, sun tunnels are generally cheaper and easier to install and maintain. Their reflective design also makes them more energy efficient.
That being said, sun tunnels don’t provide as much light as skylights do, nor do they give homeowners a view of the sky. While skylights can open if they’re vented, sun tunnels are always closed, so they also lack ventilation compared to vented skylights.
Key Differences Between Skylights and Sun Tunnels
The following table summarizes the main differences between skylights and sun tunnels:
| Skylight | Sun Tunnel | |
|---|---|---|
| Installation Complexity | More invasive, requires framing and finishing | Easier, especially when tubes are flexible |
| Light Output | High, floods room with light | Moderate, more diffuse |
| Cost | Generally higher | Typically lower |
| Energy Efficiency | Can be less efficient due to heat gain/loss | More efficient, less heat transfer |
| Maintenance | Regular upkeep, especially if vented | Minimal maintenance |
Allow me to explain these in more detail.
Installation Complexity
Skylights are generally more complex and time-consuming to install than sun tunnels.
To install a skylight, the installer needs to cut a large hole in both the ceiling drywall and the roof. After adding framing, the installer will then go up onto the roof and attach the skylight there. Next, they add insulation and waterproofing to avoid leaks, before painting the installation so that it fits seamlessly with the rest of the room. This process takes between half a day and three days, depending on your type of ceiling.
By contrast, installing a sun tunnel only takes about 90 minutes. The installer still needs to cut holes in the roof and ceiling, but the holes are much smaller than they would be for a larger skylight. This means that there’s minimal structural work after putting the aluminum tube into the holes and attaching the dome to the roof. If there are obstacles in the roof, the tubing can simply be adjusted to go around them.
Light Output
Skylights provide much more natural light than sun tunnels do.
A skylight provides so much light that it can really open up a space, often in a striking or dramatic way. Remember that skylights are huge holes in the ceiling, so homeowners will be able to see the sky as well.
Sun tunnels provide less light, but it’s still enough that some homeowners report trying to switch off the lights to darken the room, forgetting that they have a sun tunnel! The exact nature of the light provided will depend on the orientation of the roof, the season, how many trees are around and the length of the aluminum tubing. That being said, a general rule of thumb is that the light created by sun tunnels is softer and more focused than what you would get from a skylight.
Cost
Skylights typically cost more to install than sun tunnels, because they’re larger and require a more complicated installation process.
In general, the larger the skylight, the more expensive it is. Vented skylights also cost more than fixed ones. The cheapest skylights start at around $1,500 for materials plus labor, and they run up to $6,000 on the higher end.
By contrast, you can install a sun tunnel for between $500 and $2000. If you’re a DIY sort of person and want to keep costs to an absolute minimum, you could even buy the parts for between $200 and $500 and install the unit yourself. Bear in mind, however, that this increases the risk of leakage compared with if you get a professional to help you.
Energy Efficiency
Sun tunnels are generally more energy-efficient than skylights.
Skylights are so massive that they have a significant impact on the temperature of the room they’re in. During the winter, a lot of heat can escape through the skylight, particularly if it’s vented, meaning you’ll have to pay more to heat your home. Conversely, during the summer, the sunlight shining through the skylight can really heat up a room, meaning that you’ll need to spend more on your AC. These issues can be mitigated to some extent with modern glazing, but only partially.
Sun tunnels are much smaller, so they have less of an impact on your home’s energy footprint. They don’t open like vented skylights, and they don’t require the installer to add extra insulation. They just transport the light from the roof to your room, and that’s it.
Maintenance
Skylights generally require more maintenance than sun tunnels.
Consider that a skylight is basically a window on the top of your roof. Like all windows, skylights accumulate dirt and debris, so require regular cleaning. If you have a vented skylight, you’ll also want to oil the opening mechanism regularly to make sure it works correctly. These maintenance concerns are even more important if you live in a region like Texas which is prone to extreme weather events, such as hail.
Sun tunnels are much smaller than skylights and can’t be vented. This means they collect minimal debris, so require very little maintenance once set up.
Considerations for Choosing Between Them
Type of room
The larger your room, the likelier it is that a skylight will be a better fit for your needs. Conversely, if you want to light up a small, confined space, a sun tunnel is a great choice.
If your room already has a vaulted ceiling, it probably already looks rather grand, so go with a skylight to amplify the effect. For a flatter ceiling, a sun tunnel can brighten up the room in a subtler, quieter way.
In cases where your room needs better ventilation, a vented skylight is the only option that adds both light and airflow. If your home is already well-ventilated, then you can make your design choice without worrying about this factor.
Financial constraints
We’ve already mentioned that sun tunnels are cheaper than skylights on average, so if you’re working with a smaller budget, a sun tunnel is probably a better choice.
But consider that skylights offer more ways to qualify for a Federal Solar Tax Credit. The important thing to get the credit is that the lighting fixture must have an element that’s solar-powered. Both lighting types can qualify, but skylights are so big that you could even add solar-powered blinds, if you wanted. Either way, make sure you factor in the 30% credit into your financial calculations.
On the other hand, the resale value of skylights might be lower. Both skylights and sun tunnels improve the aesthetics of your home, but some buyers view skylights as too much hassle to take care of.
Roof design
The type of roof you have on your home can impact which type of light makes most sense for your family.
Skylights work best on sloped roofs, since the angle maximizes the amount of sunlight they draw into the room. They can be tricky on flat roofs, since water will sometimes collect on top of the window. That being said, it’s possible to get around this by installing a frame to elevate the skylight slightly.
If you have a metal roof, it might make installing a skylight tricky, since the ridges and seams of the metal could block the installation. That being said, with the proper flashing, it can be done. Just be aware that a metal roof plus a skylight might make for a very hot summer!
Skylights are almost impossible to install if there are mechanical elements between the roof and the ceiling, such as an air duct or plumbing vents. In this instance, a sun tunnel will work much better, because you can simply bend the tubing around the elements.
Sun tunnels are generally much less affected by the type of roof you have than skylights. They’re hardest to install on flat roofs that don’t get enough natural light, but using a dome can get around this problem easily enough. Sun tunnels work on just about any type of roof, whether flat, sloped or metal, and regardless of how many mechanical elements are between the roof and the ceiling.
Design preferences
Homeowners differ in their design preferences. If you’re looking to create a dramatic visual impact, go with a traditional skylight. On the other hand, if you’d rather add something low profile and minimalist, a sun tunnel is going to be a better fit.
The more that your lighting choice is a stylistic one to open up the room as a whole, the more likely it is that you need a skylight. The more that you’re just looking to add light as a solely functional upgrade, the more likely it is that you’d be better off with a sun tunnel.
Wrapping up
Skylights and sun tunnels are not the same thing. Both lighting types have their place in the market, depending on your needs as a homeowner.
If you want to add tons of natural lighting and ventilation in a dramatic way, and don’t mind spending a bit more, go for a skylight.
If your budget is a bit tighter, you need less light and your roof makes installing a skylight tricky, go for a sun tunnel.
Either way, we recommend hiring a professional to help you install your lighting safely, and prevent future expenses down the line caused by incorrect installation. To bring in an expert from Presidio Roofing, call (210) 679-1065 today!
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