Stone and slate roofs across Crosshills, with skylights and rooflights for its terraces and cottages

What to ask the council

The questions are the same in any council area. Is the street inside a conservation area? Is there an Article 4 direction, which would withdraw the permitted development right for a rooflight? Is the building listed, in which case consent is needed before any new opening is cut? For an ordinary unlisted house, the usual answer is that no application is needed, and the conditions are set out on the planning page on permitted development and regulations.

Neighbours across the boundary

Rooflights on a neighbour's roof are a poor guide. A house that looks the same may sit under a different council, and a unit that went in without trouble elsewhere may not be allowed here. The only reliable check is the position of your own house on your own council's map.

Flats and converted buildings

A flat has no permitted development right for roof alterations, so an application is usually needed. That covers flats made from larger stone houses or from old mill buildings, and it is a point to settle with the freeholder and the council together.

Why it helps to ask early

An enquiry about a definite unit in a definite position gets a straight answer. It is easier for the council to say yes or no to a rooflight of a named size on a named slope than to a general question about roofs. The reply can then be used for the work itself.

Looking at the roof from the loft

The first thing we do is look up. From inside, the underside of the slates shows whether there is felt, torching or bare battens, and whether any timbers are damp or soft. A sound roof gets a straightforward fitting. Soft battens are replaced where the opening will be, so the frame has a firm fixing.

Some roofs have been re-slated at a later date, and the line between the old work and the new can often be seen in the loft. A part of the roof with felt and a part without can sit side by side, so the position of the window is checked against the underside at that exact spot.

Cutting the opening

The new opening is framed with timbers between the rafters, and because that changes the roof structure it is notifiable (we notify Building Control). The slates round it are lifted by hand, and the battens are trimmed back to the line of the frame. The membrane is laid over the new timbers and turned up beside the frame on every side.

Dust from the underside of the slates

An old roof with torching sheds grit and lime dust when it is disturbed. The floor and stair below are covered before work begins, and the loft is cleared of stored items near the opening. Once the frame is fixed and the lining is plastered, the dust is cleaned from the room.

Stone gables and slate edges

Some terraced houses here have stone gables and a stone coping at the ends of the roof. A window near the gable would crowd the coping, so the unit is placed on regular rafters towards the middle of the slope, where the slates are a continuous sheet and the flashing has room.

Where a roof window does count

In a bungalow or chalet bungalow the rooms in the roof lie within that height, so a roof window can be their way out. It then has to open to at least the size that Approved Document B sets, so the choice of unit is made early. We take the figures from the document itself and never guess at them.

What the window gives the room

A roof window gives a loft bedroom daylight from above and a way of letting stale air out. A centre-pivot unit swings on its middle and suits a room with furniture beneath it, while a top-hung unit opens outward from the head and leaves clear space under the glass. For a bed under the slope, centre-pivot is the usual pick.

Stone houses and the loft stair

In an older stone house the stair often rises steeply in a narrow shaft between two walls. Enclosing it to fire standards can take space from the rooms around it, so the stair is considered before the windows are. The window position follows once the layout of the stair and the room is clear.

Planning and the stair together

Because the stair and the window affect each other, the layout is settled in one visit: where the new stair flight lands, which wall carries the fire-resisting lining, and where the window sits above the bed. A plan drawn on the day avoids a window that lines up with nothing.

Headroom at the edges

Rooms under a pitched roof have low edges. The window is placed so its sill is above the lowest useful part of the floor, and the light well is splayed to spread daylight across the slope. This keeps the room usable up to the point where the ceiling meets the wall.