Bath is a World Heritage Site, and much of the city lies within a conservation area. Many of the grandest terraces and crescents are also listed buildings. A listed house needs consent before a rooflight is added, and inside a conservation area a short email to the council costs nothing and can save an awkward refusal. Our rooflight planning guide lays out the steps and what the planning officer will want to see. Old rooflights in these roofs were cast iron and sat very low, which is why a conservation rooflight tends to be the answer here: a slim steel or aluminium frame with a central glazing bar, hugging the slate rather than reading as a modern box.
Plenty of those units open. A sash worked by a handle or a pole lets an attic room air without changing what the roof looks like from across the valley. In Bath the view from the hills counts, because the city is seen from above as well as from the street, so the slope facing the opposite hillside gets more thought than the one facing a back garden.
Mansards, valleys and the shape behind the front
Georgian roofs in Bath are rarely a plain pitch. Many have a mansard, with a steep lower slope and a shallower upper one, and others are a pair of parallel roofs with a valley gutter between them. The gutter sits behind the parapet and carries water to a downpipe at each end. A rooflight beside a valley has to be placed so it never gets in the way of the water, and the lead at the junction needs dressing carefully. Our surveyor climbs into the loft as well as up the ladder, and says honestly if a unit would sit better a metre to one side.
The timbers matter just as much. Rafters in a roof of this age were cut by hand and rarely sit at the spacing a drawing would show, so we measure what is actually there and suggest a width that avoids awkward trimming. Putting in a new unit with its own frame and glass counts as building work that goes through Building Control, and our guide to the regulations shows how that is handled.
A tall house can share the job across its two slopes. The front, which may be seen from a crescent or the street, takes one small conservation unit sized to what the council will accept. The rear, over the back bedrooms and the garden, takes a wider roof window that swings open, with a trickle vent so the room never goes completely still. The top floor gets daylight from one side and air from the other, and the front of the building keeps its shape. Between the two slopes, a house that felt shut in under the roof starts to feel like a place where you could sleep through August.
Some of the largest houses in the city may have a second small stair that climbs only to the attic. Fitting a rooflight above that narrow stair is a quiet way to give the whole top floor an airing, because the stair acts as a chimney and pulls cooler air up from the floors below as the warm air goes out.
