01The short version
When a lantern needs permission and when it does not
It depends on where the lantern sits, and the roof it is joining matters more than the lantern itself.
So, do roof lanterns need planning permission? Sometimes, and the cause is almost always the same. A plain rooflight or skylight on a house roof is covered by permitted development, which means national rules let you do it without applying. One condition is that the glass may stand at most 150mm proud of the roof slope. A lantern is a raised, multi-sided glass roof, and it stands well proud of the surface it sits on. So it falls outside that allowance on the main roof of a house.
Where most lanterns in south Essex go is different. They sit on a flat roof, usually a single-storey rear or side extension, over a kitchen-diner or family room. There the question shifts. You are no longer asking about a rooflight allowance. You are asking whether the extension itself, with a lantern on top, still fits the rules or the permission it was built under.
Lantern on the main house roof
A lantern stands up well beyond 150mm, so this nearly always means a planning application. It also changes the look of the front or side of the house, which is what planners care about.
Lantern on an extension flat roof
Often fine without a separate application, because the lantern is part of the extension's roof. The extension's height and any conditions on it decide the answer.
02Extensions
Adding a lantern to a flat roof extension
The extension's own paperwork is the first thing to find, because the lantern adds height to whatever was approved.
Many single-storey extensions in Basildon, Wickford, Billericay and Rayleigh were built under permitted development, with no application at all. Those carry height limits, and a rear extension of one storey has a maximum overall height of 4 metres. A lantern adds to the highest point of the roof, so a flat roof that was already close to the limit may have no room for one. Measure from the ground outside, at the highest point of the ground beside the extension, up to the top of the planned lantern.
If the extension was built under a full planning permission, check the decision notice for conditions. Some limit height, roof form or materials. A lantern that breaks one of those needs a fresh application or a variation, and it is far cheaper to find that out before you order glass.
Other points that change the picture are an upper floor on the extension, a roof that sits close to a boundary, and a side-facing extension that wraps around the house. Each has its own limits, and the council can tell you quickly.
- Is the extension single storey, and how tall is its roof today?
- Will the top of the lantern stay under the height limit that applies?
- Does the original decision notice carry any conditions on roof form?
- Is the house a flat, maisonette or listed building?
- Is there an Article 4 direction on your street?
03Exceptions
The cases that always need a closer look
Four situations sit outside the easy route, and it helps to know which one is yours before anyone measures up.
Flats and maisonettes do not get permitted development for roof alterations at all, so a lantern there needs permission, and the freeholder or management company will have a say too. Listed buildings need listed building consent for a lantern in every case, whatever its size, and that is a separate process from planning permission. Do not start without it.
Conservation areas are less clear cut. Living in one does not by itself remove permitted development for a rooflight. An Article 4 direction can, though, and councils use these to control changes that face the street. So the honest advice is to check with the council for your own address. Our guide to skylight and rooflight planning permission sets out the national rules for ordinary roof glazing, and the Planning Portal has an interactive guide for householders at planningportal.gov.uk.
Your own council covers Basildon, Brentwood, Southend-on-Sea, Chelmsford and the other places we work in, and each runs its own planning pages and pre-application service. A short email with the address and a sketch usually gets a clear answer.
04Next steps
What to do before you order a lantern
Five steps keep a sound idea from running into a surprise letter from the council.
- Work out which roof the lantern sits on: the main house, or an extension.
- Find the extension's paperwork, whether that is a decision notice or the plans you built to.
- Check the lantern's finished height against the limit that applies to your roof.
- Ask the council about Article 4 directions, conservation area status and listed status.
- Book a free survey so the size, the build-up and the paperwork are settled together.
Planning is one gate. Building Regulations is another, and it applies to lanterns whether or not planning is needed. A new lantern means cutting into the roof structure, and it must meet current insulation limits under Part L. Where the work is notifiable we make the Building Control submission ourselves, and our page on whether rooflights need Building Regulations explains how that works.
Size comes into it as well. A bigger lantern is a taller one, and both height and warmth rise with the glass area. Our roof lantern sizes page lays out the common footprints, and the existing flat roof answer covers the build side. For the full picture of lantern choices, see roof lanterns.
Will the council object to a lantern on our extension?
Can I fit a roof lantern without telling the council?
Planning may not be needed if the extension's limits are kept, but Building Control must still be notified for a new lantern. On a listed building, a flat or a maisonette, no. Check first, because enforcement can ask you to remove a lantern that should have had permission.
Does a lantern need an architect's drawing?
Not for a lawful development certificate or a householder application on a simple job, though the council will want scaled plans and elevations. We can talk through what the application needs and give you the lantern sizes and the build-up.
Will my neighbours be consulted?
If you apply for planning permission, yes, the council notifies neighbours and takes comments. Under permitted development there is no consultation, although a friendly word over the fence is still wise.
Is a rooflight different from a lantern for planning?
Yes. A flat rooflight sits lower, though on a 150mm kerb it can still pass the 150mm projection limit, so check it. A lantern is taller, so it is judged as a roof alteration or as part of the extension below it.
