Window extensions

Things you Need to Know About Sun Tunnels

The important things to know and understand about sun tunnels by Sterlingbuild.

You may or may not know this but sun tunnels, light pipes, sun tubes - whatever you know them as - will transform a dark or windowless room into an area full of natural light and energy.

If you aren't familiar with sun tunnels, let us help you to understand all you need to know in your pursuit of welcoming more natural light into your home.

What is a sun tunnel and how do they work?

A sun tunnel is a fantastic addition to an area of your home where it hasn't been possible for natural light to get to before. They channel sunlight from your roof, down a highly reflective tube into the necessary room below.

Sun tunnels can be installed on a pitched roof or on a flat roof extension to allow daylight to flood the rooms where it's most required.

Sun Tunnel Buying Guide

What options are available for a sun tunnel?

The sun tunnel itself is available in either flexible or rigid option. Both have their own benefits which outweigh the other, and should help you choose which would be perfect for your home.

Rigid sun tunnels - the better of the two available, rigid sun tubes give you a better light transmittance than the flexible sun tunnel. Rigid sun tunnels allow for the light to channel down the tube from roof to ceiling in a direct motion. The less the light bounces off the internal surface of the tube, the more natural light you will get in the required room. Rigid sun tunnels can offer up to 20m of effective light distribution.

Flexible sun tunnels - the low cost solution for adding natural light. Perfect for shorter distances, the flexible tube allows you to negotiate around obstructions in the roof space. VELUX flexible sun tunnels can be installed up to a recommended length of 6mDue to the build of the flexible tube, light will reflect less in a flexible sun tunnel, effectively directing the light away from its required destination, resulting in less light reaching the required room. 

Sun tunnels come with either a dome or flat glass cover. Sterlingbuild are the sun tunnel experts.

Rounded dome or flat glass cover?

You’ll see that some sun tunnels have a dome that sits on top of the roof, whereas others have a flat glass panel. The panels are stylish, almost flush with the roof and can be installed to match existing windows. Domes look the part, sitting proudly above the tiles/slates and standing out as a feature on your roof. But what difference does either one actually make?

There is only one important thing to note here, and that is how light reflects off a flat surface but refracts when it meets a clear dome. This means once the light hits the flat panel, some of the light is lost by means of reflection. It’s only good news for domes here because they actually refract the light inwards and so capture extra light compared to their counterparts.

Positioning is key...

So you've decided on the type of tube you want, whether it's flexible or rigid, as well as the external aesthetics of your sun tunnel. The next thing to think about and consider is the position of the sun tunnel on your roof.

(This next point is more important if installing a sun tunnel on a pitched roof and can be disregarded if you're looking to install one on a flat roof.)

Are you lucky enough to have a garden that is south-facing? If the answer to that question is 'yes' then I am very jealous of you. South-facing gardens see the most amount of sunlight during the day and are seen as the ultimate sun trap. The same can be applied to a pitched roof.

And by this fact, installing a sun tunnel on the south-facing side of the roof (or the side of the roof that is as close as possible to south-facing) will mean your sun tunnel will get the most amount of natural daylight available.

Coupling this with the installation of the sun tunnel as close to the apex of your roof as possible means, once again, you will get the most amount of natural daylight available.

But don't worry; ambient light from north, east, or west facing roofs will still make a huge difference!

 VELUX sun tunnels available at Sterlingbuild. How many do you need for your home? Find out in our blog.

How many sun tunnels do I need for my room?

The more you install, the better the results.

As with vertical windows and skylights, the more space you give daylight to get into your room, the better the results. We advise you purchase the biggest you can, and aim for 1 or 2 sun tunnels to be installed in the centre of your room, or a handful of smaller sun tunnels evenly spaced around the room. The brilliant thing about a sun tunnel is that they are suitable for any room and won't look out of place! 

This chart shows which sun tunnel size is best suited to a type of room.

Tunnel diameterRoom sizeRoom type 
15.5cm0-4m2Small rooms, cupboards and short corridors
23-25cm4-10m2Hallways, small bathrooms or specific area of a larger space
32-45cm11-15m2Large hallways, stairwell and bathrooms
52-55cm16-22m2Kitchens, bedrooms and living rooms

Save money on your energy bills

It's a proven scientific fact that natural daylight is good for your health and wellbeing. But natural daylight is also good for your bank account!

By choosing to install a sun tunnel in your home, you will automatically see the benefits on your energy bill! The ease at which natural light will fill your home means you won't need to keep flicking on those lights during the day - saving you money on your energy bills! Your home will become warmer as well with the added welcome of natural daylight.

Why not install a sun tunnel into a wall?

The Lightway F400 vertical sun tunnel allows for even more customisation when choosing how to light up your room. Vertical sun tunnels enable you to bring light in from a side wall and illuminate areas in your home that don't receive natural day light, such as basements and ground floor flats. The design of these sun tunnels allows the diffuser to be fixed into a wall so the light does not have to come from the ceiling.

At Sterlingbuild, we stock a wide range of sun tunnels from the best brands in the industry, at affordable prices. We have a variety of shapes and sizes available, to suit a number of roofing types from tile to slate.

Don’t believe us? Take a look for yourself. Browse our range of sun tunnels from VELUXLightway and Sterlingbuild.

If you have any questions about sun tunnels, please get in touch with our team.

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