THE PROBLEM
Rooms the daylight never reaches
Every building has them. A landing with no window. A bathroom in the middle of the floorplate. A corridor lit by fluorescents at two in the afternoon. An office that goes gloomy four metres from the glazing.
The usual answers are all poor. Leaving a light on costs money and looks it. Cutting a window into a wall needs a wall to cut into. Opening the roof up needs the room to be under the roof, and most of these are not — or are, but with a void, joists and services in between.
Which is the gap tubular daylighting fills: real daylight, delivered to a ceiling that has no roof directly above it, without structural work.
WHERE IT WORKS
Rooms this solves
| Room | Why it is dark | What usually suits it |
|---|---|---|
| Internal bathroom or ensuite | No external wall, no roof above | Smaller tubular system |
| Landing or stairwell | Enclosed by rooms on all sides | Smaller tubular system |
| Hallway or corridor | Long, narrow, no glazing at either end | One or more tubular systems along the run |
| Kitchen at the back of a house | Light falls off with depth from the window | Larger tubular system, or a rooflight if the roof allows |
| Deep-plan office | Daylight does not carry past the perimeter | Larger tubular systems, or rooflights over the plan |
| Storeroom, utility, garage | Never had a window | Smaller tubular system |
| Basement or lower ground | Below the building entirely | Neither — this needs a different approach |
The last row is honest rather than helpful: a tubular system needs a route to the roof. Where there is a floor in the way, it is not the product.
HOW IT WORKS
Three parts, no structural work
Roof to ceiling
- 1 A dome on the roof captures daylight from the whole sky, not just from directly overhead.
- 2 A highly reflective tube carries it down through the roof void, around obstructions where it has to.
- 3 A diffuser set into the ceiling spreads it into the room, so it reads as ambient daylight rather than a spotlight.
FEASIBILITY
What decides whether it will work
Almost every disappointing installation traces back to the void, not the product.
The run. Distance from the underside of the roof deck to the finished ceiling. Shorter and straighter is brighter.
What is in the way. Purlins, joists, ducting, cabling, water tanks. Every bend costs light, so a route that has to dogleg around a tank may need a larger unit than the room size alone would suggest.
The roof covering and slope. These decide the flashing, not the unit. Tile, slate, metal and flat membrane all differ.
Where the light needs to land. The diffuser position in the ceiling is not always free — it has to line up with a route that can reach the roof.
Ten minutes in the loft with a torch and a phone answers all four. The Measuring Guide lists exactly what to take.
THE OTHER OPTION
When a rooflight is the better answer
If the windowless room is directly under a flat roof and an opening can be cut, a rooflight gives more light per unit and a view of the sky. It is the better product where the geometry allows it.
Tubular systems win when the geometry does not: an intervening void, a room set back from the roof edge, a ceiling that cannot be structurally opened, or a case where a large glazed opening would overheat the space.
We sell both and have no reason to push you at either. Send the room and the roof and you will get the honest answer, including when the answer is that neither will do what you are hoping for.
QUESTIONS
Common questions
Will it actually be bright enough?
In most rooms, yes — enough that the light stays off through the day. It depends on the size of the unit, the length and directness of the run, and the room. Tell us the floor area and the run and we will tell you honestly if it is marginal.
Can I put one in a rented property or a flat?
It involves work to the roof, so it needs the freeholder's or landlord's consent, and in a flat you need a roof you have rights over. Worth settling before you price it.
Does it need electrical work?
Not for the daylight itself — the system is entirely passive. Some installations add an electric light within the diffuser so the same fitting works after dark; that does need an electrician.
How many do I need for a corridor?
More than one, usually, spaced along the run rather than concentrated. Send the length and width and the void details and we will suggest a spacing.
Will it make the room hot in summer?
Far less than an equivalent amount of glazing, because the roof penetration is small relative to the light delivered. It is one of the reasons tubular systems suit rooms where a rooflight would overheat.
Tell us about the room.
Floor area, what is above the ceiling, and how far it is to the roof. A photograph inside the void is worth more than any of it.
Performance depends on the size of the unit, the length and directness of the run, and the room. Guidance here is general; send the specifics for an answer about your building.