Skylights and rooflights for Harrogate's stone houses

What we look at before we order a unit

• Whether the house is listed. A listed house needs listed building consent before a new rooflight goes in, regardless of what permitted development says.
• Whether the street falls inside a conservation area, and whether an Article 4 direction covers it.
• Which slope faces the road. A rooflight on the rear slope is far less visible than one on the front.
• Whether the property is a house or has been divided into flats, because the rules change for flats.

Replacing a rooflight that is already there

Swapping an old rooflight for a new one in the same opening alters the roof far less than cutting a fresh hole, and a replacement that looks the same from the street tends to raise fewer questions. We still check the house first, because a listed building can need consent even for a like-for-like swap.

How big, and where on the slope

In a conservation area the practical points are how big the unit is, how many there will be, how they line up with the windows on the wall below, and how far the frame stands above the slates. A single, well-placed conservation rooflight on a rear slope is easier to justify than a row of units facing the road.

A unit for slate in a conservation area

On a slate roof in a conservation area, conservation officers often ask for a conservation rooflight. It has a slim frame, normally finished in black, often with a single glazing bar down the middle, and it sits close to the line of the slates instead of standing proud of them. From the pavement it reads as part of the roof.

Where the room could take its light from either slope, the rear one is worth weighing up first. A stairwell in the middle of a villa can often be lit from the back of the roof just as well as the front, and that choice can make the planning side simpler.

If an application turns out to be needed, the rooflight and its size are already fixed in the written quote, so the council is asked about a definite unit.

Cutting the opening

Between the rafters the opening is framed with trimmers, so the load the cut rafters carried is taken round the new frame. Cutting into the roof structure is notifiable building work, and the opening is sized on the survey to suit the rafter spacing in your roof.

Weathering it against slate

Slate is thin and lies flat, so the frame needs a flashing kit made for slate. A kit meant for a deeper profiled tile would leave the wrong gaps. The flashing lets rain run round the frame and back onto the slates below it. Above the frame, the slates are cut and laid to lap over the top of the flashing, so water coming down the slope runs onto the flashing and round the frame instead of getting in behind it.

Busy villa roofs

Big Harrogate villas tend to have busy roofs, with chimney stacks, valleys where two slopes meet and hipped ends over the stair. Each one limits where a frame can go, because it needs clean slate on all four sides and a run of rafters to sit between. Over a landing, the hipped slope can be short, which may point to a smaller roof window or a sun tunnel instead.

Glass that meets the current standard

Part L sets the figures a new unit has to meet: a roof window needs 1.4 W/m²K, or band B on the Window Energy Rating scale, and a rooflight 2.2 W/m²K. An old single-glazed rooflight in a Harrogate attic falls well short of either, so the room under the new unit loses less heat than it did before.

Making good inside

Older Harrogate houses often have lath and plaster ceilings and attic walls. We cut through carefully, insulate round the frame and plaster the reveal, finishing it as the quote describes, so the room is left ready to decorate. Old plaster throws up dust when it is cut, so the floor and the stair below are sheeted before the saw comes out, and the sheets are lifted and the rooms cleaned before we leave.

What can work in a top-floor flat

• A roof window in the slope over an attic bedroom or living room, opening for fresh air.
• A sun tunnel for an inner bathroom or hallway, where the roof sits directly above the room.
• A conservation rooflight where the building sits in a conservation area and the slope is seen from the street.

Our planning and Building Regulations guide sets out where the line between a house and a flat falls, and what that means for an application. A shared stairwell is a decision for the building as a whole, so it is worth raising with the other owners if the common stair is the gloomy part of the house.

When the roof cannot reach the room

Flats on the lower floors are harder. A sun tunnel has to run in a clear line from the roof to the bathroom ceiling, so a bathroom on the first floor of a three-storey villa would need its tube to pass through the flat above. In a case like that, we work out at the survey whether daylight from the roof can reach that room at all. A landing under an open stairwell is a different case, because the stairwell itself gives the light a clear drop from the roof.