Are Solar-Powered Roof Windows Worth It?

An electric roof window has a motor that opens and closes the sash at the push of a button or a signal from a remote or wall switch. A solar version powers that motor from a small panel built into the outer frame, and a rechargeable battery stores the energy. The window needs daylight, not full sun, to keep the battery topped up, so a north-facing slope still works, though more slowly.

The benefit is installation. A mains window needs a cable from the nearest supply to the window, and in a finished loft room that means chasing plaster or lifting floorboards. A solar window needs no cable at all, which is why it is the choice for a retrofit. You fit the window, pair the remote, and it works.

The limit is capacity. The battery has to cope with the number of openings you ask of it, and a window that is opened and closed many times a day during a dull winter spell may not always keep up. Ask the supplier how the battery behaves when daylight is poor, and how to replace it.

Mains power is steadier. A wired motor opens the window whenever you want, however dull the day, and it can be linked to a wider smart-home system. If you are renovating a room, adding a loft conversion or opening up the ceiling anyway, a cable is cheap to add at that point, and the electrician can run it alongside the lighting circuit.

Leave the mains connection to a qualified electrician, particularly in a bathroom where water and steam are present. Ask for the work to be certified, and file the paperwork with your house documents.

Solar suits a room that is already finished, a window that is hard to reach, or a roof where nobody wants to chase cables. It costs more than a manual window and often a little less to fit than a mains one, because it saves the electrical work. The motor premium depends on the model and the electrical work, so the figure comes in the written quote after the survey. For the window alone, Checkatrade's October 2026 table shows £1,250 as a UK average for fitting a new one.

Many electric windows come with a rain sensor, a small pad on the outside of the frame that detects moisture. When rain falls, the sensor tells the motor to close the sash, even if you are out. For anyone who leaves the loft window open to air the room on a warm day, it removes the worry of coming home to a wet carpet.

It is not a guarantee. A heavy shower with strong wind can reach the room in the seconds before the sash closes, and a flat battery or a power cut can leave the window open. A sensor that has been covered by leaves or moss may not notice the rain at all. Wipe the pad clean when you clean the glass, and test the closing now and then.

Some people also use the closing feature for security, shutting the window at a set time. A window that is open only a small amount for ventilation still lets the room breathe without leaving a gap a person could use. Our answer on whether roof windows are secure goes into this. If water does get into the room, look at why a Velux window leaks.

The value of a motor depends on the window. For a roof window you can reach and open by hand, a motor adds cost without much gain. For a window over a stairwell, a high landing or a double-height space, it turns an unused window into a useful one, and it also lets people with limited reach or strength open it.

Solar is the better buy when the alternative is opening up finished rooms for a cable. Mains is the better buy when the work is going on anyway. Ask yourself how often you would use the window, and whether you could manage with a manual pole instead.

Fitting an electric window into an existing opening is the same roof job as any other replacement: new flashing, careful relaying of the covering around it, and a lining that finishes the reveal. If the opening is being enlarged, see replacing a Velux with a bigger one.

Send us a photo of the window, the room below and the height of the sill from the floor. We will tell you which type suits the position, and the single total in writing arrives once we have been up to look. Our roof windows and skylights page lists what we fit.