A Guide to Roof Lanterns: Styles, Glazing and Choosing the Right One

Roof lanterns are one of the most effective ways to bring natural light and a sense of height into a home. This guide explains what a roof lantern is and how it differs from a skylight or a flat rooflight, and covers roof lantern installations from styles and glazing through to specification and planning.

What Is a Roof Lantern?

A roof lantern is a raised, glazed structure that sits on top of a flat or low-pitched roof and rises above the roofline. Instead of lying flat, its glass panes slope upwards and meet at a central ridge or a single apex point, forming a shape that looks a little like a glass roof in miniature.

This raised design does two useful things. It captures daylight from several directions across the day, so a room stays brighter for longer than it would under a single flat pane. It also adds height and a feeling of space to the room below.

Most modern roof lanterns, including contemporary and pyramid designs, use a slim aluminium frame. Aluminium is strong, so the glazing bars can be kept narrow, which means more glass and more light. Traditional and period styles are also available in timber or timber-effect finishes for a heritage look.

Roof Lantern, Skylight or Rooflight: What Is the Difference?

These three terms are often used as if they mean the same thing, but there are real differences worth knowing before you buy.

Rooflight

“Rooflight” is the broad, catch-all term for any glazed unit set into a roof to let daylight in. Every skylight and every roof lantern is a type of rooflight. If you are comparing the full range of rooflights and skylights available, this is the umbrella category they all sit under.

Skylight

A skylight, sometimes called a flat rooflight, usually sits flush or nearly flush with the roof as a single flat or gently sloping pane. It gives a clean, minimal look and works well where you want daylight without adding height.

Roof lantern

A roof lantern is a specific type of rooflight that stands proud of the roof as a raised, multi-faceted structure with several sloping glazed faces. It is more of a design feature than a flush skylight, drawing in light from different angles and creating a focal point both inside and out.

In short, a rooflight is the category, a skylight tends to sit flat, and a roof lantern rises above the roof as a statement.

Roof Lantern Styles (Contemporary, Pyramid and Period)

The most suitable style depends on the shape of the opening, the age of the property and the overall look required.

Contemporary

Contemporary lanterns have slim sightlines and clean lines, usually with a central ridge and sloping faces (a hipped design). The narrow aluminium bars, similar to those used in roof lanterns, maximise the glass area, so they suit modern extensions where you want as much open sky as possible.

Pyramid

A pyramid lantern has four equal triangular faces that rise to a single central point, with no ridge. It suits square or near-square openings and gives a neat, symmetrical result. Our pyramid roof lantern is a good example of this design and can be built to fit your opening.

Glazing and Materials Explained

The frame and glass you choose affect how warm, bright and low-maintenance your lantern will be.

Frame materials

Aluminium roof lanterns are the most popular modern choice. Aluminium is strong and low maintenance, and it takes a powder-coated finish in a variety of RAL colours, with a different colour inside and out. Good aluminium frames are thermally broken, meaning a non-conductive layer set inside the frame slows heat loss, and high performance seals reduce air leakage further.

Glazing options

Double glazing is standard, and triple glazing is available where thermal performance is the priority. Beyond the number of panes, the glass itself can be specified to do a particular job:

• Solar control glass reduces solar gain and helps stop a room overheating in summer, which matters most for south-facing lanterns.

• Laminated glass has a tough interlayer that holds the pane together if it breaks, which improves safety and security. For overhead glazing this is often the sensible choice, and you can see it in our glass roof lantern.

• Tinted, neutral or obscured coatings are available where privacy or appearance matter.

Thermal performance and U-values

A thermally efficient roof lantern depends on the combination of frame, glazing and installation quality. Thermal performance is measured as a U-value, in watts per square metre kelvin (W/m²K). The lower the U-value, the less heat escapes and the better the energy efficiency. A well-made double-glazed aluminium lantern with a thermal break and a low-emissivity (low-E) coating performs well, and triple glazing can improve it further.

Building Regulations in England and Wales (Approved Document L) set a maximum U-value that new and replacement rooflights must meet. Ask any supplier to confirm the whole-unit U-value, not just the figure for the glass.

Where Roof Lanterns Work Best (Kitchen Extensions, Orangeries and Flat Roofs)

Roof lanterns come into their own on single-storey spaces that would otherwise feel dark towards the centre.

Kitchen and rear extensions

A single-storey rear extension often has a wide floor plan and a flat roof, so its centre can feel gloomy. A lantern over the kitchen or dining area brings daylight straight down into that space and makes an open-plan layout feel larger.

Orangeries

An orangery combines solid brick pillars with a flat roof and a central lantern. The lantern gives the room its light and character, and period styles suit this setting particularly well.

Flat roofs

Roof lanterns are designed to sit on a flat or very low-pitched roof, on top of a builder-formed kerb (an upstand built around the opening). Whether you are building a new flat roof extension or fitting a lantern to an existing flat roof, purpose-made flat roof lanterns are built to sit securely on this kerb and weather correctly. The kerb also gives the lantern its height and helps it drain.

How to Choose and Specify the Right Roof Lantern

A few practical decisions will get you to the right specification.

Size and proportions

Measure the opening carefully. Suppliers usually quote lanterns to the external kerb size, so confirm whether yours works to the kerb size or the internal daylight opening. Taller lanterns look better on larger openings, and many ranges relate the height to the width for balanced proportions. Standard sizes exist, but few extensions are truly standard, so a made to measure lantern is often the neatest fit, though this typically comes with a longer lead time than a standard unit.

Colour, glazing and ventilation

Choose your frame colour first (the inside and outside can differ), then match the glazing to the room. South-facing rooms benefit from solar control glass, and hard-to-reach lanterns benefit from self-cleaning glass, which reduces the need for manual cleaning glass at height. Decide early whether you want fixed glazing or an opening vent for ventilation, as this affects the frame you order.

Kerb, structure and installation

The opening in the flat roof must be structurally framed to carry the lantern. The kerb needs to be the correct height and square. Agree who is building the kerb and who is fitting the lantern, and make sure the weatherproofing detail where the lantern meets the roof is clear before work starts. Most roof lantern installations are straightforward once the kerb is built correctly, and a well-specified lantern should be easy to install onto a properly prepared upstand.

Frequently Asked Questions

What is the difference between a roof lantern and a skylight?

A skylight usually sits flat or flush with the roof as a single pane, while a roof lantern is a raised structure with several sloping glass faces that rises above the roofline. A lantern brings in more light from different angles and adds height, while a skylight gives a lower, more minimal finish.

Do I need planning permission for a roof lantern?

Many roof lanterns on single-storey rear extensions fall under permitted development and do not require planning permission, though there are limits, for example on height and on front-facing elevations. In most cases a roof lantern doesn't need formal approval, but listed buildings and properties in a conservation area are treated differently, and Building Regulations still apply to the structural opening and to thermal performance. Always check with your local planning authority before you commit.

Can you put a roof lantern on a flat roof?

Yes. Roof lanterns are designed for flat and very low-pitched roofs and sit on a raised kerb built around the opening. The kerb gives the lantern its height and helps it drain and weather correctly.

What size roof lantern do I need?

Choosing the right lantern size depends on your opening and the proportions you want. As a rule, a lantern should be generous enough to light the space below without overwhelming the roof, so measure the kerb opening before you order.

Do Skyseal roof lanterns come with a warranty?

Yes, Skyseal roof lanterns are supplied with a 10-year warranty as standard, covering the frame and glazing against manufacturing defects.

Ready to Choose Your Roof Lantern?

A roof lantern is a long-term addition to your home, so it pays to get the style, glazing and specification right from the start. Browse our full selection of roof lanterns to see the styles and options, or get in touch for a quote and we will help you specify a lantern that suits your project.