Turning the sash so the outside faces you
A pitched roof skylight that opens is built to be cleaned from the floor: the sash rotates until the outer pane is inside the room and within reach.
On a centre pivot window the handle runs along the top of the sash. Pull it down and the sash swings on hinges set halfway up the frame, the top edge coming into the room and the bottom edge going out. Keep turning and the sash goes past the ventilation angle and over until the outside of the glass faces the ceiling below you. Most ranges have a small bolt or catch on the side of the frame that holds the sash in this reversed position, so it cannot swing back while you are working on it. The sequence is simple:
- Clear the sill and anything below the window, and lower or remove any blind that runs in the side channels, following the blind maker's instructions.
- Open the window fully and keep turning the sash until it is close to upside down.
- Slide the barrel bolt or catch into place so the sash is held firm.
- Wash, rinse and dry the outer pane, then the frame edges you can now see.
- Release the catch, turn the sash back and close the handle so the seals pull tight.
Take the weight with both hands as the sash passes the halfway point. A large window carries a heavy double or triple glazed unit, and it is easier to control with a steady hand on the frame than by the handle alone.
Top hung, side hung and fixed units
Each opening type gets the outside pane to you in a different way, and a fixed skylight is the one that cannot turn at all.
A top hung window lifts outwards from its top edge for ventilation and a view. For cleaning, most ranges add a second movement: a release catch lets the sash pivot through the middle, just like a centre pivot window, so the outer face comes into the room. That is why these windows are often sold as dual function. A side hung escape window opens like a door to one side, which brings part of the outer face within reach from the opening, although you should never lean out to do it. Our guide to the types of roof window covers how each one opens, and the comparison of top hung and centre pivot windows weighs cleaning against reach and view.
| Window type | How the outer pane is reached |
|---|---|
| Centre pivot | Sash turns over and locks |
| Top hung (dual function) | Second pivot position |
| Side hung escape | Opens aside, reach from the opening |
| Fixed or out of reach | Rain, coating or water-fed pole |
What to use on the glass
Warm water, a drop of washing-up liquid, a soft cloth or sponge and a rubber squeegee are all the outer pane needs.
Avoid scouring pads, razor blades, powder cleaners and strong solvents. They can scratch the glass, mark the aluminium cladding and harm the rubber seals that keep weather out of the frame. If the window has a self-cleaning or easy-clean coating, check the manufacturer's care guidance: some coatings should not be treated with silicone-based products or rubbed hard, because that can stop them working. Wipe the gaskets and the frame edges while the sash is turned, and lift out any leaves or seed heads caught in the top of the frame.
Work on the outer pane before the inner one. Rinse water can run down onto the inside face and the lining while the sash is reversed, so finish with the inner side and a dry cloth along the sill.
When the window is out of reach
A roof window set high in a vaulted ceiling or over a stairwell may be out of reach even when it turns, and a fixed skylight never turns at all.
Rain does part of the work on a steep slope. On a typical Cambridge terrace roof pitched at 35 to 45 degrees, rain washes loose dust off the glass fairly well; a shallower roof lets dirt settle for longer, which is one reason roof windows for low-pitch roofs are often specified with self-cleaning glass. For a high window, a telescopic pole can reach the operating bar or an electric motor can open it, and a window cleaner with a water-fed pole can wash the outside from the ground or from a safe standing point. That method uses purified water and leaves no spots.
What you should not do is climb out onto the roof or lean through the opening. Tiles and slates are slippery, the edges of an open sash are not a handhold, and a fall from a roof is a serious injury. If a window cannot be cleaned safely from inside or from the ground, that is a job for someone with the right access equipment.
Planning for cleaning before the window goes in
How easy a roof window is to clean is decided at the planning stage, by its height, its opening type and its glass.
A sash you can reach from the floor is a sash you can turn and wash. Setting the handle or operating bar within a comfortable reach, and leaving space below so a chair or bed does not block the turn, matters as much for cleaning as it does for opening. Our guide to positioning a roof window in a room sets out sill and head heights. In a double height room or a vaulted ceiling, an electric window and self-cleaning glass are worth weighing together, and the roof window glazing options guide explains what each pane offers.
The slope matters too. A north-facing slope stays damp for longer after rain and can grow green algae around the frame, while a south slope dries quickly but shows every smear against low winter sun. Clean glass lets the most light into the room, so we treat cleaning access as part of the light plan rather than an afterthought. Every roof window installation we quote sets out the opening type, height and glass with the reason for each. To see how it would work in your loft, book a light survey.
Questions people also ask
How often should the outside of a roof window be cleaned?
There is no fixed interval. A steep slope in open ground may only need a wash in spring and autumn, while a window under trees, or near fields at harvest, may need one more often. Clean when the glass starts to dull the light in the room.
Is it safe for children to help turn the sash?
Turning a heavy sash is an adult job. If the window is in a child's room, restrictors and locks can limit how far it opens day to day, and our answer on making a roof window child safe explains how they work alongside the cleaning position.
Can I clean the window while it is raining?
It is better to wait for a dry spell. With the sash reversed, rain lands on the inner pane and runs into the room. The answer on leaving a roof window open in the rain covers what an open sash does in wet weather.
Does self-cleaning glass mean it never needs washing?
No. A self-cleaning coating uses daylight to break down organic dirt and lets rain sheet off, so the glass stays clearer for longer, but bird droppings, tree sap and heavy dust still need an occasional gentle wash.
