Garforth skylights and rooflights for bungalows, semis and loft rooms

How the tube gets through the loft

Roofs built from the 1960s onward are often framed with factory-made trussed rafters, set close together with diagonal timbers between them. We map the route on the survey so the tube passes between the timbers, and the dome is small enough to fit between rafters. Should the route need a timber cut, the opening alters the roof structure, and that work is notifiable.

Straight tube or a bend

A straight drop is best. Each bend costs light, so when the hall is not directly under the roof slope we look for the shortest rigid run, using a short flexible section only where a joist forces it. The diffuser is positioned in the ceiling to suit the hall, usually over the point where the doors meet.

What it does to a bungalow hall

On a bright day the hall is lit by daylight without a switch being touched. The hall keeps its ordinary ceiling light for the evening, and the tube adds daylight to it by day.

Making good in the hall

The diffuser sits in a neat opening cut in the ceiling board, with the edges taped, filled and painted to match. Dust from the board is caught by sheeting laid down the length of the hall, so the carpet and the front door mat stay clean. The loft hatch is the only way up, so we protect the hatch frame as well.

Where the tube starts on the tiles

The dome sits on a flashing that is bedded into the tile courses, and we lift the tiles round it and lay them back over the flashing so the water runs off as it does elsewhere on the roof. On a concrete tile roof Because the flashing is shaped for the profile, we note the tile type when we survey.

If you would rather have a window that opens, a roof window is possible where a loft room sits over the hall. A bungalow hall usually has only a loft void above it, which suits the tube better.

Where the loft is already a room

If the loft has been boarded and converted into a bedroom, a roof window is a normal part of that room, and the stair below it gets its light through the opening at the head of the flight. Where a conversion already has a window in the rear slope, a second one over the landing is a separate decision.

Two storeys and a loft room

A loft room above two existing storeys counts as a third, and the escape rules apply to it. A roof window is not the escape route there; Approved Document B calls for a protected stair. That is a matter for the designer of the conversion, and we leave the escape arrangements to them. For a bungalow with rooms in the roof the position is different, and a roof window can serve as an escape window within the height limits.

What the slope is made of

Where a Garforth semi carries concrete tile, which is thicker than slate, the tiles are lifted by hand around the opening. A flashing kit built for the tile profile is fitted and the tiles are dressed back up to it. Tiles that crack in the lifting are replaced with the closest match to what is on the roof.

Chimneys and party walls

A chimney stack or a party wall running up through the roof limits where the frame can go, because the rafters on either side of it are fixed. If the best position for light is blocked by one, we look along the slope for a clear stretch, and a smaller window placed a little to one side often serves the landing just as well.

Choosing the front or the back slope

The rear slope is the quieter choice on a semi: it faces the garden, away from the street. Our summary of what permitted development allows for roof alterations covers the conditions, and the cases, such as flats, where they do not apply.

Sizing it to the room

A garage ceiling is low, so a lantern would stand above the room more than it should. A flat rooflight sits close to the roof surface and keeps the ceiling clear. We measure the room on the survey, look at the size of the opening the roof can take, and set the rooflight over the part of the floor that needs it.

The roof underneath

Some garages have a flat roof of felt, or have been given a new covering during the conversion, so the upstand is made in the same material. If the garage has a pitched roof with a ceiling below it, either a pitched-roof window or a sun tunnel takes the place of the flat unit.

Keeping the room warm

Converted garages need to hold their warmth, and a rooflight is a place where heat can leave. A double or triple glazed unit with a warm-edge spacer and a low U-value keeps the loss down. The rooflight must reach 2.2 W/m²K under Part L, and the figure is explained under how efficient skylights are.

What the ceiling hides

Garage conversions vary in what they leave behind. Some have the old joists left bare, and some have a new ceiling hung below an insulated roof. Before we cut, we find out which one it is, because the opening has to be framed to carry the roof whichever way it was built. The light well down to the ceiling is lined and finished so the room has a clean edge.

Fitting day

The roof is opened, the upstand is built and weathered, the unit is set, the ceiling below is lined and plastered, and we handle the notification to Building Control. After that the room is cleaned, with the sheets lifted and the dust gone.