Guide · Compare
Heliostat vs. Solatube vs. sun tunnels
All of these bring daylight into dark spaces — but in very different ways. A light tube pipes light down from the roof; a heliostat aims real sunlight wherever you want it. Here's how to choose.
The quick answer
- Choose a light tube / Solatube if you have a suitable roof above the room, want a passive fix, and don't need to aim or schedule the light.
- Choose a heliostat if the room has no usable roof access (e.g. lower floors), if you want to direct sun to a specific spot — indoors or outdoors — or if you want control, scheduling and winter performance.
Side by side
| Heliostat | Solatube / sun tunnel | |
|---|---|---|
| How it works | Tracks the sun and reflects a beam to your target | Passive shaft pipes roof light down |
| Installation | Outdoor mount; uses an existing window | Roof penetration + ceiling work |
| Aim / schedule | Yes — app-controlled, multiple spots | No — fixed |
| Lower-floor rooms | Works (no roof needed) | Hard or impossible |
| Outdoor use | Yes — terrace, garden | No |
| Low winter sun | Actively re-aims to catch it | Weak when sun is low |
| Moves with you | Retrofittable / removable | Permanent |
What each is best at
Solatube and sun tunnels
These are proven, low-maintenance and invisible once installed. For a top-floor bathroom, hallway or walk-in closet directly under the roof, a light tube is often the simplest answer. The trade-offs: it needs building work, it can't be redirected, and it delivers diffuse light only where the tube ends.
Heliostats
A heliostat is the flexible, active option. Because it sits outside and reflects through a window, it reaches rooms that no roof shaft can — including ground-floor and shaded rooms — and it can put sun on a desk at 9 a.m. and a reading chair at 4 p.m. It's also the only one of the three that works outdoors, reclaiming a shaded terrace or garden seat.
A note on cost
Light tubes are usually cheaper to buy but add installation labour and roof work. A premium home heliostat is a higher up-front device cost, but it's retrofittable, needs no structural work, and you can take it with you. The right choice depends less on price than on where you need the light and whether you want to control it.
Want to aim daylight, not dig through the roof?
The ohoya Heliostat redirects real sunlight to any spot — indoors or on the terrace — with app control and no building work. Reserve from €49, fully creditable and refundable.