Short version
Expect roughly £500 to £1,200 fitted on typical UK market figures, meaning a rough guide only, never a price from us. What moves a job within that band is the tube diameter, the choice of a rigid or a flexible tube, how long it is and how many bends it has, the roof type and any light kit. Our written quote follows the survey, because the roof and the route decide the figure.
What the sun tunnel cost range covers
The range above is a general UK market range, and a place to begin, not a quote from us. It assumes a standard home with a reasonable route from roof to ceiling. The full set of ranges for other units is on our costs page.
The tubular skylight cost for your own house is set after the survey, once we have seen the roof covering, the loft and the ceiling below. The written quote follows that visit, and the job plan names the unit before any money is asked for the work.
Two houses on the same street can land at different ends of the range. A bungalow with a short drop through a shallow loft is a simpler job than a landing under a deep two-storey roof, even when both want the same size of diffuser.
Diameter and light output
Sun tunnels come in different tube diameters, and a wider tube carries more daylight and costs more. VELUX's own guidance compares a 14-inch tube to roughly a 60W bulb in good conditions, which is the manufacturer's comparison and not a promise for your home.
The right size depends on the room. A small landing or cloakroom may be well served by a narrow tube, while a hallway or a larger bathroom may justify a wider one. The diffuser at the ceiling follows the tube, so it affects the finish inside as well.
Rigid or flexible, length and bends
A rigid tube has a reflective inner surface and carries light further with less loss. A flexible tube bends around obstacles and is quicker to place, but it carries less light over the same length. The trade-off is covered in rigid or flexible sun tunnel.
Each extra metre and each elbow takes some light away, so a long run with several turns costs more and delivers less. Rooms with a straight, short drop get the most from the money. The limits are discussed in the note on how long a sun tunnel can be. A short straight drop from roof to ceiling is the simplest and least expensive case.
| Factor | Effect on cost |
|---|---|
| Tube diameter | Wider tube, higher unit cost |
| Rigid or flexible | Rigid usually costs more, carries more light |
| Length and bends | Longer, more turns, more parts |
| Roof type | Tile, slate and flat each need a different flashing |
| Light kit | A lamp or extra diffuser adds to the unit |
Roof type and access
The roof covering decides the flashing. A pitched tile or slate roof takes a flashing sized to the covering, while a flat roof uses a base and upstand, as shown in our note on sun tunnels on flat roofs. Access to the loft and the height of the roof also affect the time needed on the day.
A ceiling that needs making good after the diffuser goes in is part of the job, and the plan says who does what. The survey records all of these points so none is found on the fitting day.
Loft insulation is another detail. The tube passes through it, and the plan notes how the insulation is dealt with around the tube so the ceiling stays tidy.
Ceiling finish and making good
Where the tube meets the ceiling, a hole is cut and a diffuser fitted. In a plasterboard ceiling this is a tidy job. In an older lath and plaster ceiling it needs more care, and the edges are finished to suit. The plan notes what is included and what you would paint or decorate yourself afterwards.
A bathroom or landing with limited headroom may take a shallower diffuser. A deep loft with insulation to the rafters can need a longer tube. We measure for each at the survey and show it against the unit row in the quote.
Where the tube leaves the roof matters as well. The position is chosen so the run is as straight as the loft allows, clear of rafters, water tanks and wiring. A move of a few hundred millimetres can remove a bend, and that can matter more to the light you get than a larger tube would.
Tell us which room is darkest. We look at the route from that ceiling up to the roof, and the plan records the final position, the diameter and the tube type for you to approve before anything is ordered.
If you are also having a room redecorated, tell us at the visit. Timing the sun tunnel before the paint goes on saves a second round of decorating, and avoids dust settling on a freshly finished ceiling or landing wall.
Light kits and what your quote shows
A light kit adds an electric lamp to the tube so the room is lit after dark as well. It needs a power supply in the loft, which appears as a separate item in the quote. Without one, the sun tunnel works by daylight only.
Your written quote lists the unit, the diameter, the tube type, the roof flashing and any light kit, with the fitting day and lead time in the job plan. Building Control notification is made by us when it is required, and the 10-year workmanship guarantee comes in writing with the quote. For the bigger question of whether one suits your home, read are sun tunnels worth it, or see the sun tunnel installation page.
If you are weighing two quotes, check that both name the same things: the tube diameter, rigid or flexible, the length and bends allowed for, the roof flashing, the diffuser and the ceiling finish. Two figures can look far apart when one of them leaves out the loft work or the making good. Our plan names each item against the route measured at the survey, so a change of diameter or tube type shows its effect on the written figure before you agree to anything.