Rooflights and skylights for stone cottages in Knaresborough and the attic rooms above their stairs

A window or a tube

A roof window suits a stair that sits directly under a roof slope with space for a frame between two rafters. A sun tunnel suits one where the slope is short or the rafters are close, because the dome is small and the tube is flexible enough to find its way round a timber. A straight route gets rigid sections, which send more daylight down than a flexible tube over an equal run.

Old timbers and what they leave

The timbers of an old roof are not always evenly spaced, and some were cut by hand. We look from the attic hatch at where each rafter falls, since a frame between two of them keeps the structural work small. Where a rafter has to be trimmed, the opening is framed with trimmers to carry the load. Cutting the opening changes the roof structure, so we notify Building Control.

Flashing for an old slate

Old slate is brittle and the slates differ in size and thickness. Around the opening the slates are taken up by hand, the sound ones are stacked, and they go back over a flashing made for slate. A broken slate is swapped for the closest match on the roof.

A light well in a deep roof

Where the roof timbers are deep, a lined light well runs from the frame down to the stair ceiling. It is plastered white inside, so it carries the light down to the flight instead of absorbing it.

Finishing the stair ceiling

Inside, the opening through the stair ceiling is lined and plastered, and the edge where it meets the old plaster is finished so the join does not show. Old ceilings may be lath and plaster, which throws up dust when cut, so the flight below is sheeted and cleaned once the frame is in.

Permission in the old town

North Yorkshire Council, a unitary council, takes planning questions for Knaresborough, and the permitted development guide for rooflights explains when a house roof needs an application.

Walking the route

Before the work is planned, we look at how a delivery would reach the house. A pallet can be left at the nearest point a vehicle reaches and carried the rest of the way, and a frame that is too wide for a stair is passed up the outside. Where the only way to the roof is through the house, we protect the rooms along the way.

Scaffold on a steep street

Work on the slope that faces the road needs a scaffold on the pavement or the lane, and the highway authority may have to give permission for that. On a hillside the ground can fall away at the back of the house, so a scaffold there is built to suit the slope. For a small opening on a rear slope, a scaffold tower or a roof ladder with a working platform can be enough.

Choosing the quieter slope

If the room below could take its light from either slope, the one away from the road is usually the easier one to reach and the one a street sees least. A hillside house sometimes presents its roof to a lower street as well, so we check which slopes are seen from where before one is chosen.

Where slates and timber wait

Slates, timber and waste need somewhere to sit while the roof is open. On a narrow street that means stacking tidily at the foot of the scaffold and keeping the pavement or lane passable for neighbours. Loads are carried down by hand as the work goes on, so little builds up outside.

Keeping the stair and landing clean

On a narrow stair every carried load passes close to the walls. Floors and handrails are covered before the first piece of timber goes up, and the sheets stay down until the opening is closed and the dust has been cleared.

What a conservation rooflight is

Conservation rooflights come with a slim steel or aluminium-faced frame, normally black, and frequently one glazing bar running down the centre of the glass. The unit lies low against the roof line, which suits traditional slate and stone roofs. Conservation officers often ask for one in a conservation area.

When an ordinary roof window is enough

A house rooflight usually counts as permitted development while it rises at most 150mm clear of the slope and keeps below the roof's highest point. On a rear slope away from the street, an ordinary roof window with a slate flashing often sits well enough with the roof. Whether the property is a house, a flat, listed or inside an Article 4 area changes the picture, so the council is asked, and the planning guide lists the conditions.

Swapping an existing attic rooflight

An older attic may already have a rooflight, and a replacement in the same opening disturbs the roof less than a new cut. The new unit is chosen to sit as the old one did, so from the street the roof reads unchanged. Listed status is checked first, because consent may be needed even where a unit is replaced like for like.

Rooflights on listed houses

On a listed building, consent is needed before a new rooflight goes in, and permitted development rights do not change that. An application is for a definite unit in a definite place, and the written quote gives North Yorkshire Council a precise unit and position to consider.

Keeping the line of the roof

On a slope the street can see, the count of units and the way they sit above the windows below weigh as much as the frame. One rooflight placed over the stair keeps the roof line quieter than a row of them across the front.