Skylight and rooflight fitting in Llandeilo

The A483 crosses the River Tywi at Llandeilo on a stone bridge of the 19th century. Its railway station lies on the Heart of Wales Line, and the road and railway bridges over the river both interest engineers. The 2021 census counted 1,784 people in the community, and in 2021 The Sunday Times named Llandeilo one of the top six places to live in Wales.

The place is far older than the bridge. Roman soldiers were active around Llandeilo about AD 74, and the foundations of two castra turned up on the Dinefwr estate. Roman roads linked Llandeilo with Llandovery and Carmarthen, and a small civil settlement outside the fort's gates may have carried on as the beginnings of the town after the Romans left, around AD 120. Dinefwr Castle still overlooks the Tywi close to the town, and the estate of Golden Grove lies nearby, with Carreg Cennen Castle further off. The Church of St Teilo became a mother church to the surrounding district and held the Gospel Book of Saint Teilo, a manuscript noted for its fine illustration. Owain Glyndŵr's march through the Tywi Valley in July 1403 put the town to the torch.

Llandeilo is roughly 24 road miles north of Swansea, well inside the 30 miles we cover. The town stands next to the westernmost point of Bannau Brycheiniog National Park, outside it, and the next chapter explains what the Park boundary means for planning. Two neighbours on the map, Ffairfach and Llandybie, are inside our area as well.

Whatever the street, the roof comes first. On a pitched slope the fit is a roof window, set level with the slates or tiles. A flat-roofed utility room or kitchen addition leaves two routes: a kerbed rooflight, or a lantern that has its own upstand. A landing with no outside wall and a loft overhead suits a sun tunnel. Each answers the weather in its own way, and that decides the product more than the room does.

Stone-and-slate houses of the older kind tend to have steeper, narrower back slopes than later semis, which leaves space for one roof window at a time. That describes the type. The roof you own may differ.

Carmarthenshire County Council takes planning applications for a Llandeilo address. On the Welsh Government's map there is a conservation area named Llandeilo close to the centre of Llandeilo. A new rooflight on a house inside a conservation area needs planning permission in Wales, and a map cannot tell you which side of the line your own front door falls. The council can, and so can the county's page on conservation areas.

The westernmost point of Bannau Brycheiniog National Park lies next to the town, which is outside the Park. Inside the Park boundary the Park Authority is the planning authority, and a rooflight there needs planning permission as well. The Gower AONB lies elsewhere, and its rules for rooflights have no bearing on a Llandeilo address.

Elsewhere, on an ordinary house, a rooflight can be permitted development when it meets the conditions in our skylight planning permission guide for Wales. Flats and maisonettes have no such rights, and the council can withdraw them from a house with an Article 4 direction, as a planning condition on the original permission can too.

A listed house is another matter. A rooflight that would alter its special character needs listed building consent under the Historic Environment (Wales) Act 2023. You apply through the local planning authority, Cadw is consulted, and Cadw's own guidance points out that even minor work can need consent. Settle that before anything is ordered.

When a case sits on the line, ask the planning team for their view. For a firm answer, apply for a Lawful Development Certificate, which records the council's decision in writing.

Building Regulations run alongside all of this. Cutting a new opening for a rooflight generally brings Building Regulations approval into play: making the opening usually changes the roof structure, and the roof that is left must be able to hold the unit, with strengthening if it cannot. You may choose between the local council's building control team and a private registered approver, and either counts as a building control body. Where the work is notifiable, we handle the Building Regulations notification with local authority building control or a registered building control approver.

Start under the slope. A bedroom in the roof takes a gusty evening on its glass, and a window left ajar can let the weather in. Manufacturers such as VELUX offer rain sensors on electric roof windows, which close the window as rain arrives, so the room can stay aired through the day and shut itself against a shower. Our page on electric opening rooflights explains the controls.

An old window may only need swapping. VELUX stamps a size code, MK04 or UK04 for example, on a metal type sign at the top of the sash, where it shows when the window is open, and the code tells you the width and height. The new window should reach 1.4 W/m²K, or Window Energy Rating Band B, under Approved Document L (Wales). Our roof windows page has the options.

A swapped window brings ventilation into the picture. Trickle vents in the old frame hint at what the new one needs, so mention them when you describe the window, and the replacement can be specified to keep the airflow that the room already had.

A landing has the opposite trouble. There is no wall to hold a window, and a loft or roof sits overhead. A sun tunnel carries daylight down a short tube from a dome in the roof, and the dome on the roof is compact. On a grey afternoon it lights the top of the stairs softly and evenly.

Over a kitchen extension, the flat roof rooflight is a unit raised on a kerb, and the roof falls away around it. A rooflight in Wales should reach 2.2 W/m²K under Approved Document L (Wales). If you are weighing a roof lantern, the roof lanterns page covers the upstand, and a lantern added to a brand-new extension is a point we settle with the council first.

On an older house of character, a conservation rooflight is built with traditional roofs in mind, and it is the type to put to the council for any period house. A unit that has misted between its panes can be replaced, and our misted rooflights page shows what that involves.

The first visit is a free survey. A fixed written quote follows it, and once the work is finished you hold a 10-year workmanship guarantee in writing. Call 01792 929062 or use the survey form.