Electric roof windows
Can a manual roof window be made electric?
The short answer
Often, but not always. Whether a manual roof window can be made electric depends on the make, model and age of the window, and on whether a power supply or a solar panel can reach it. Some windows take an electric or solar operator as a retrofit. Others are better replaced. The label on the frame and a look at the opening settle it.
What changes when a hand-operated roof window is motorised, and the checks that decide whether it is worth doing.
Converting the window or replacing it
There are two routes to a motorised roof window. One is to fit an operator to the window you already have. The other is to swap the whole unit for a new electric one in the same opening. Which is possible depends on the window. Every roof window carries a label on the frame giving its type and size, and that label tells us whether the maker still supplies a motor for that model.
Older windows are the usual obstacle. A frame that is decades old may no longer have a matching kit, and the glazing and seals may be near the end of their life anyway. Motorising a window that is about to need replacing means paying twice. Where a conversion is possible and the window is sound, it is the smaller job. Where it is not, replacing the unit is neater. Our page on replacing a Velux window explains how that works, and the skylights and roof windows hub shows the other work we do on them.
Power from the mains or from the sun
An electric operator needs a supply. Some are wired to the mains through a small control unit, which means a cable run from the window to a socket or fused spur, usually chased into the wall or hidden above the lining. Others take their power from a solar panel fixed on the roof beside the window, charging a battery, with no cable through the house.
The solar route suits a loft room with no convenient wiring and a window that faces the light. The mains route suits a window you will operate often, or one on a north slope that needs a dependable supply. Either way, the electrical side belongs with someone qualified to do it, and you should ask the supplier what happens in a power cut. A window that cannot be opened by hand when the power fails is a problem in a bedroom.
Cable routes and the panel position are settled during the visit, since they decide whether plaster or roof covering gets disturbed.
Rain sensors, blinds and windows out of reach
People usually ask because the window is out of reach. A roof window set high over a stairwell, a landing or a bath is awkward to open with a pole, and a motor with a wall switch or remote solves that at once. Many electric windows can also take a rain sensor that closes the window when drops land on the glass, which helps in a loft room you leave empty during the day.
It helps to know what the sensor does and does not do. It reacts to rain on the glass, so it is no substitute for checking that the window is shut when you go away or when a gale is forecast. We would suggest fitting one only where you really do leave the window open, because every extra part is something that can need a visit later.
A motorised blind is a separate product that shares the wiring, so decide on it at the same time rather than reopening the lining later. Remote controls and wall switches can be grouped so one press works both blind and window.
Safety, escape and building rules
If the window is the way out of a loft room in a fire, how it opens matters more than how it is powered. Check that an electric window still opens fully by hand, or on a battery backup, when the mains is off. Our guide to roof windows as a fire escape sets out what to ask the supplier before you commit.
Fitting a motor to a window already in the roof leaves the roof itself alone, so it is a different thing from putting in a new roof window. If the whole unit is replaced, the new one has to reach the thermal target for roof windows in Approved Document L: a U-value of 1.4, or a rating of Band B in the Window Energy Rating scheme. Your building control body can confirm how that applies to your home.
The specification belongs to the supplier, so ask for the data sheet for the exact model on your roof before ordering. Motors, brackets and sensors differ between models and between years, and a part that fitted a neighbour's window may not suit yours.
What decides the price
There is no sensible fixed figure, because the same request covers a simple retrofit kit on a window within easy reach and a new electric unit in a roof with a long cable run to a distant socket. Four things set the price: whether the window converts or is replaced, the type of power, the length of any wiring, and whether blinds or a rain sensor go in with it. Access to the roof comes into it as well, since a high or steep slope needs more equipment to work from.
Once the survey is done, we put one total in writing. It rests on photographs of the window, its label and the route for the supply, so you can see why we recommend conversion or replacement. To see what fitting a window costs in general, read Velux installation cost. Anything stripped out leaves with us when we finish.
Related questions
Powered window questions
Is solar operation reliable enough for a bedroom window?
It can be, on a roof that gets daylight, but a panel in shade charges poorly. We would look at the slope, the light and how often you open the window. In a bedroom we would also want a way to open it by hand if the battery runs flat.
Will fitting an electric opener disturb my slates or tiles?
A mains operator is usually wired inside the room, so the roof stays untouched. A solar panel is fixed beside the window and its small cable passes through the existing flashing area, and we protect the covering and the seals when we do it.