Skylights and rooflights for the stone cottages of Lepton

Thick and uneven

A stone slate varies in thickness from one to the next, and its lower edge is irregular. A flashing meant for thin, flat slate would sit proud of the surface and let water get beneath it. A kit made for a deeper covering is used, and the slates that meet the frame are shaped to fit.

Handling the old slates

Stone slates are a material worth keeping. They come off by hand, are stacked in order and go back round the frame, and a cracked one is replaced with the closest match the roof can supply. Old stone is brittle, so the cutting is done slowly and the sound slates are laid aside first.

Slates that cannot be matched

Where a roof has lost slates over the years and been filled with odd replacements, the area round a new frame is a good moment to tidy it. We say so in the quote if extra slates are needed, and old stone slates from the opening itself often supply them.

Weight and the rafters

A stone slate roof is heavy, and its rafters and battens were laid to carry it. The new opening is framed with timbers that pick up the load of any rafter that has to be cut, and the work is structural and notifiable. The window width is picked from the gaps between the rafters you actually have.

How the roof is shaped

The shape of the roof matters as much as the covering. A cottage with a plain gabled roof has two long slopes and a clear ridge. A house with a hipped end, or a roof that turns a corner, has valleys where the slopes meet, and those are no place for a frame. The bare slope on the side away from the lane is generally the cleanest option for the opening.

Choosing the position

A window needs clean covering on every side and clear rafters behind it. On a cottage roof the chimney stacks, the gable ends and the valleys all limit where the frame can go. We mark the position from inside the attic, where the rafters can be seen.

Where the covering is slate or tile

Welsh slate and concrete tile each take their own flashing kit, and we compare the two kits in VELUX flashings for slate and tile.

Listed houses

Listing brings a separate consent for any new rooflight, and that stands apart from the permitted development rules. The application is judged on what the opening does to the historic roof. A small unit in the rear slope is the easier proposal to put forward.

Conservation areas

Inside a designated area, an Article 4 direction may withdraw permitted development rights that a house would otherwise have. The council can confirm whether one reaches your street. Even where none does, the look of the roof from the lane deserves thought before the position is fixed.

What a conservation rooflight looks like

The frame is slim and usually black, and a single glazing bar often runs down the centre of the glass. The whole unit lies close against the roof line, because it was designed for slate and stone. Owners whose houses have no protection at all sometimes choose one anyway, because it draws less attention.

Front slope or back

Where a room could be lit from either side, the slope turned away from the road deserves a first look. It is less visible from the street, which can ease an application. Where the house is listed, listed building consent for a rooflight is the process that applies.

What goes to the council

Whatever is required, the planning officer wants a definite unit and size. Our written quote settles both before any work starts, and we notify Building Control where the work is notifiable, so the same figures can go on the application.

A roof window over the stairwell

A window in the slope above the head of the stairs lights the landing from above. If the stairwell is open, some of that light runs down the flights and reaches the hall. The window can also open, which clears the warm air that gathers at the top of an old house.

Where the ceiling is low

Cottage ceilings can be low, and the roof can be close above them. A sun tunnel suits that case, since the tube is short and the diffuser needs no light shaft. For a deeper space between the ceiling and the slope, a roof window with a shaft is the better fit; light wells and reveals explains how the shaft is shaped.

The cold stone and the glass

An old stone attic can be cold. The limit for a rooflight is a U-value of 2.2 W/m²K, while a roof window must do better, at 1.4 W/m²K or Window Energy Rating B. Coated double glazing in a thermally broken frame reaches both figures, and it keeps more warmth in than the single pane an older cottage might still have.

Finishing round the opening

Where the ceiling is lath and plaster, the opening is cut with care and the floor below is sheeted to catch the dust. The sides of the shaft are lined and plastered smooth, and splayed so the light spreads outward into the landing. White paint on those sides helps it.

Dust sheets and the stair

The stair carries the dust of the job down with it, so the treads and the hall below are covered before the ceiling is opened. The covers stay down until the plastering round the opening is dry and the rooms have been cleaned.

Cloakrooms and pantries

A downstairs cloakroom that was once a pantry may have a ceiling that opens straight to the loft. A sun tunnel can reach it by a short run if no bedroom lies directly above.