What are the alternatives to a skylight?

A sun tunnel, sometimes called a light tube, is a small dome on the roof joined to a reflective tube that drops through the loft to a diffuser in the ceiling below. It carries daylight into a landing, hallway, cloakroom or en suite where a full window would not fit. Because the opening in the roof is small, the work is lighter than a roof window: a short length of the covering is cut, a flashing is bedded around the dome and the tube is run down to the ceiling.

What you give up is the view and the ventilation. A tunnel does not open, you cannot see out of it, and the quality of the light depends on the length and straightness of the run. Bends and a long run reduce brightness. It suits a pitched roof with a clear route down to the room. It is less suited to a room with a deep floor above it, which makes the run too long to be useful.

A sun tunnel is also a fixed-point leak risk like any roof penetration, so the flashing detail matters. We check how it will sit against the tile or slate coursing before we agree to it.

A dormer is a box built out of the roof slope, with its own upright window and its own small roof. It adds floor area and headroom, which a roof window cannot. If your problem is a low, cramped loft and not just a lack of daylight, a dormer solves both, at a higher price and a larger programme of work.

The planning position is the catch. Roof additions come under GPDO Class B, which stops short of article 2(3) land, a category that includes conservation areas and the Cotswolds National Landscape. Over half of Stroud District lies within that landscape, and the district has 41 conservation areas, so a dormer often means applying for planning permission where a roof window might not. Check with Stroud District Council's planning team before drawing anything.

Our answer on dormer or roof window for a loft compares those two in depth, so it is the better read if the choice is between them alone.

If the house has a gable end, the triangular wall that closes the end of a ridged roof, a window in the wall can bring in more light than a roof window and look more natural. It is a masonry job rather than a roofing one. A lintel is built into the stone or brick, the opening is cut, and a normal window is fitted. In a stone wall that means a mason, careful lintel work and matching the surrounds and the pointing so the new opening does not look like an afterthought.

The restriction is the building itself. A terraced or semi-detached house may have a gable end shared with a neighbour, and a gable that looks onto a boundary raises overlooking questions. Planning rules for walls differ from those for roof slopes, and a listed building or an Article 4 area can tighten them. A gable window is also off the table in a hipped roof, which has no gable.

Gable windows are worth considering in a loft conversion where the wall allows it, as they often combine well with one or two roof windows on the slope.

Sometimes the least expensive answer is not a roof opening. Good artificial lighting, pale finishes and a reflective surface opposite a source of daylight make a gloomy room feel brighter. Borrowed light, where a glazed internal door or a glass panel lets daylight pass from a bright room into a dark one, can also work in a loft stairwell without any roof work.

These routes suit a room used briefly or at night. They do not provide ventilation, they do not provide an emergency exit, and they do not change how the room feels in the way real daylight does. Building Regulations also look at ventilation and escape in a loft room, so a bedroom lit only by lamps still needs a proper route out. Our answer on fitting a roof window from inside is worth reading if you decide that a simple opening is the answer after all.

The honest comparison is by job size. A sun tunnel is a small penetration, a roof window a bigger one, a gable window a masonry job and a dormer a structural alteration. On the roof window side, MyBuilder's 2026 guide puts installation at £350 to £600 for standard jobs and scaffold at about £500, which are national guide ranges and not what we charge. It gives no comparable figures for the other options in this list, so we price those only after seeing the roof.

We photograph the roof, the loft and the room at the survey, then send a written quote that covers every item of the work. If the best answer for your house is not a roof opening at all, you will hear that from us. Read how long a roof window takes to fit before you decide, and see the skylights and roof windows page for the whole service. Any roof work we carry out has a 10-year workmanship guarantee in writing.