Not every room gets to have a window. Whether it’s an attic, hallway, bathroom, or internal kitchen, plenty of spaces in a home are starved of natural light. The usual fix is artificial lighting, but there’s something missing when you rely on bulbs alone. Sun tunnels can change that entirely.
They bring in real daylight, straight from the roof into the darkest corners of the house. But buying one isn’t as simple as picking the cheapest option online. Different rooms need different solutions. Get it wrong, and you might waste money or end up with barely any improvement in light.
So, if you’re planning to add a sun tunnel, here’s how to choose the right one for each type of space.
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First, Understand How Sun Tunnels Work
A sun tunnel, sometimes called a light tube or tubular skylight, channels sunlight through a highly reflective tube from the roof to the ceiling of a room. At the top, a clear dome or flat panel collects the sunlight. Inside the roof cavity, the tube carries that light through bends or straight runs, and it ends in a diffuser on the ceiling that spreads soft daylight into the room.
This makes them ideal for areas that can’t support a traditional skylight. You get natural light without needing a full window, and they’re often easier to install than you might expect.
But just because sun tunnels work in many spaces doesn’t mean one type fits all.
Look At The Room First, Not The Tunnel
Before thinking about sizes or features, start by assessing the room itself. What’s missing, what’s possible, and what are you trying to improve?
Ask yourself:
Is the space small, medium, or large?
Is it used during the day or mostly at night?
Does it have a loft or ceiling space above?
Are there any obstacles between the roof and ceiling?
Do you want a subtle glow or strong daylight?
Every one of these questions affects your choice. A compact hallway won’t need the same amount of light as a large open-plan kitchen. And if there’s a tight loft space or beams in the way, you might need a flexible tunnel rather than a rigid one. When you buy sun tunnels online, having a clear idea of your space helps you pick the right fit more confidently and ensures you get the best result for your room.
Flexible Vs Rigid Sun Tunnels
This is one of the first big decisions to make.
Rigid sun tunnels deliver brighter, cleaner light. The mirror-like interior bounces the light more efficiently, and they’re ideal for longer runs or when you need a strong, bright result. But they can’t bend easily. So, they only work when there’s a clear, straight route from roof to ceiling.
Flexible sun tunnels, on the other hand, are easier to install around obstacles. If you have ductwork, pipes, or awkward angles in the roof, these can curve to fit. The light might not be quite as strong or sharp, but they still bring a big difference in darker spaces.
For most rooms with simple roof access, a rigid tunnel will be the best choice. But in older houses or tight loft spaces, flexibility can save you a lot of hassle and cost.
Choosing The Right Size
The size of the tunnel has a direct impact on how much light it brings in. Larger tunnels bring in more daylight but also take up more ceiling space and require more work during installation.
Here’s a rough guide based on room type:
- Small bathrooms, closets, pantries – 250mm or smaller
- Hallways, stairwells, utility rooms – 250mm to 350mm
- Kitchens, living rooms, large bathrooms – 350mm to 550mm
- Open-plan areas or lofts – 550mm and above
It’s worth remembering that one large sun tunnel often brings in more usable light than two smaller ones. But if your roof structure limits diameter, spacing two smaller tunnels might be the only option.
Don’t Ignore Tube Length & Roof Type
Not every house is the same. A shallow roof with an easy loft void is ideal, but what if your ceiling is far below the roof or there’s a pitched attic in the way?
In these cases, measure the vertical distance from where you want the diffuser to the outside of the roof. Long tube lengths can reduce light output unless you go with a high-quality rigid tunnel with a highly reflective surface.
Also, check your roof type. Some sun tunnels are made for flat roofs, others for pitched. Always match the unit to the structure, or you’ll end up with leaks, poor fit, or worse performance.
Think About The Diffuser Style
This is often overlooked, but it makes a difference in how the light feels in the room.
Frosted diffusers – soften the light and reduce glare. Best for bedrooms, bathrooms, or places where you want a gentler feel.
Clear diffusers – give brighter, sharper light. Ideal for kitchens, utility areas, and large spaces that need strong natural light.
Some diffusers also come with added features like dimming, blinds, or integrated lights for night use. If the room is used around the clock, these extras might be worth considering.
Extras That Might Be Worth It
These additions aren’t essential, but depending on the room and your budget, they can make a good sun tunnel even better:
- Light kits – Add electric lighting inside the tube so it can function like a regular light at night.
- Ventilation kits – Useful for bathrooms and utility spaces where airflow is important.
- Integrated blinds – Let you control the amount of daylight entering, helpful for bedrooms or media rooms.
- Energy-efficient coatings – Help regulate heat and reduce UV if the tunnel faces harsh sun for most of the day.
Light Up Your Home Naturally
A well-chosen sun tunnel brings more than just daylight. It lifts the mood of a space, makes it more usable, and reduces reliance on artificial light. Whether you’re brightening a gloomy hallway or making a kitchen feel more open, there’s a sun tunnel out there that fits the job.
Just remember, it’s not about picking the biggest or most expensive one. It’s about understanding your space, your needs, and how sunlight can flow naturally through your home. Once you get that right, the rest falls into place.
