Roof lanterns
Roof Lantern Installation for Flat Roofs
A roof lantern brings daylight into a room from above, especially where side windows leave the centre of an extension shaded. We fit roof lanterns for flat roofs and orangeries, considering the roof structure and room layout alongside the glazing.
Place daylight where the room needs it
A lantern can light the centre of a kitchen, dining room or orangery rather than relying only on glass along the outside walls. Start with the furniture and the way you use the space. A dining table, island or seating area may benefit from overhead light, but the best position is not always the geometric centre of the roof.
Consider what can be seen from neighbouring upper windows and how the sun moves across the room. More overhead glass also changes glare and summer sunlight, so size should follow the room's needs rather than a preference for the largest opening possible.
A flat roof lantern needs a proper roof opening
The lantern is a glazed structure sitting above a prepared opening, with a raised roof junction around its base. The supporting roof and the edge of that opening need to be suitable for the assembly. It is not simply glass placed over a hole cut between existing timbers.
The survey considers the existing roof construction, the proposed opening and how loads will be carried around it. Where structural changes are needed, they should be defined before installation is agreed. Any roof covering that will remain also needs assessment so the new junction can work with it.
Replacing or adding to an existing roof
An existing flat roof may be suitable for a lantern, but condition and structure decide the answer. A tired covering, restricted ceiling space or roof members in the proposed position can affect the work. A new lantern should not be installed on the assumption that every existing roof can accept it unchanged.
If the room is part of a planned extension or orangery, the lantern opening can be designed with the roof from the start. Think about lighting, ceiling finishes and any services in the roof zone before fixing the position. Resolving those details early avoids competing arrangements around the finished opening.
Glass, frame and the view overhead
The glass specification affects daylight and comfort, while the lantern's frame pattern shapes the view towards the sky. Compare the appearance from inside the room as well as from the garden. A decorative ridge or several frame divisions can look different at ceiling height from a brochure view.
Insulation, seals and the complete roof junction matter alongside the glass. No glazing choice replaces the need for ventilation and sensible heating in the room below. Discuss exposure to sunlight and what you want from the space so the proposed specification addresses more than appearance.
Weathering and future access
Rainwater needs a clear route around the raised opening and away across the roof. The junction between the lantern, supporting upstand and roof covering is a critical part of the work. Roof drainage should be considered with the new installation rather than left as a separate problem.
Plan how the external glass and surrounding roof can be maintained safely. A roof that is visible from upstairs is not necessarily safe to stand on. Appropriate access and cleaning guidance matter, particularly where the lantern sits above an extension with limited access from the garden.
Approvals and a defined installation scope
Changes to a roof opening can involve structure, thermal performance and glazing safety, so building regulations need consideration. Planning requirements also depend on the property and the external change. Check the approval route before committing, especially where the building has restrictions.
We offer a free survey with a fixed written price and no-pressure quotations. The size, roof condition, structural work, glazing and internal finish all affect the scope. Use the form below to discuss a roof lantern on an existing roof or as part of a planned glazed room.
Questions
Common Questions
Can a roof lantern go on an existing flat roof?
Sometimes, if the roof structure and condition are suitable. The opening, support and weathering need assessment. Structural or roof-covering work may be needed before a lantern can be fitted.
Do roof lanterns need building regulations?
The work can involve structure, energy performance and glazing safety, so building regulations consideration is important. Confirm the required approval with building control for the specific project before installation.
What affects roof lantern cost?
The size, glazing, frame arrangement, existing roof condition, opening support and ceiling finish all influence the quote. Access and any required structural work should be included in the agreed scope.
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