Electric rooflight cleaning and care, in ten minutes twice a year

Four things: clean glass, clear drainage channels, seals that are soft and seated, and a sensor that can see the weather. Everything else was the installer's job at the time of fitting.

The reason the list is short is how the unit is built. A motorised skylight is a sealed glazed sash, a frame with a drainage path, a run of rubber or foam seals and a drive that pushes or pulls the sash through a fixed stroke. The drive is enclosed. You do not grease it, open it or adjust it. What sits outside and gets dirty is the glass, the frame and the seals, and what sits inside the room is the control. So care is mostly wiping, looking and keeping things free of grit.

There is a second reason to keep up the routine, and it is the one we talk about most at Clear Skylights: sound. A rooflight that closes cleanly onto a soft, clean seal is quiet in rain and quiet in wind. Grit on a seal, or a sash that stops a few millimetres short of the frame, gives you a whistle in a gale and a tick in a shower. Clean seals are a large part of why a room stays calm, and the written quiet spec that comes with each quote names the seals for exactly that reason.

If you want the mechanism explained first, how electric opening rooflights work walks through the sash, the drive and the stop points. It helps to know what you are cleaning around.

Twice a year for the full routine, and a glance whenever you happen to look up. Spring and autumn are the natural pair, because they bracket the seasons of pollen, leaf fall and the first hard frost.

Think of it as two tiers. The full routine below takes about ten minutes for a single unit and a little longer for a long run of them over a kitchen extension. The glance takes seconds: is the glass clear, is the sash sitting flat when closed, is anything hanging in the channel.

Units under trees want the autumn visit most. Units on a clean flat roof in open ground can stretch the gaps between cleans, and south-facing glass tends to show dirt sooner than north-facing glass because the sun bakes it onto the surface.

Use lots of clean water, a soft cloth or sponge and a mild soap, and never scrub dry dirt across the surface. Modern rooflight glass often carries a low-emissivity coating on an inner face of the sealed unit, and the outer face is frequently treated to shed dirt, so the aim is to lift the grime, not grind it.

Work in this order and it goes quickly:

1. Close the rooflight fully and keep the control out of reach of children while you work.
2. Rinse the glass with a hose or a bucket of clean water to float off grit and pollen. Dry dust acts like sandpaper if you wipe it first.
3. Wash with warm water and a small amount of mild washing-up liquid on a soft sponge or microfibre cloth.
4. Rinse again until the water runs off in clean sheets.
5. Dry with a clean chamois or a soft cloth, or let it air dry on a dull day to avoid streaks.

Avoid abrasive pads, blades, scourers, solvent cleaners, white spirit and anything labelled as an oven or limescale cleaner. Strong chemicals can attack the seals and the frame finish long before they trouble the glass. Bird droppings and sap soften with a wet cloth laid over them for a few minutes, then lift away without force.

Reach decides how you clean, so take it seriously. Clean from the inside where you can. For the outside face, use a soft brush on a long pole or a hose-fed pole from the ground, or reach from a solid, guarded area. Never walk on a rooflight unless it is a walk-on unit designed for that. The glass of a standard rooflight is not a floor, and a wet surface is slick. Flat roofs have edges, and a roof with no edge protection is not somewhere to kneel with a bucket. If the glass cannot be reached safely, a window-cleaning firm with a pole system and the right access equipment is the sensible answer, and worth the fee.

A rooflight frame is built with a path for water to escape, and that path blocks with leaves, moss and silt if nobody looks. Keeping it open is the most valuable job in this guide.

Look along the outside of the frame at the base, where the sash meets the lower edge. You are looking for slots, weep holes or a shallow channel, depending on the make. Their job is to let rain that finds its way past the outer seal drain away instead of sitting. When a slot is full of compacted leaf mould, water has nowhere to go, it sits against the seal, and in a hard frost it freezes and pushes on the frame.

Clear the path gently. A soft brush, a wooden cocktail stick or a plastic spatula does it. Do not use a screwdriver, a pin or a wire, which can scratch a coating or push debris deeper. A flush with a little clean water afterwards shows you whether the water runs freely to the outside. If it does not, stop and work more slowly, rather than forcing anything.

The metal or timber frame gets the same treatment as the glass: warm water, mild soap, a soft cloth, rinse, dry. Powder-coated aluminium stays handsome for years if kept clear of grime. If a coating looks dull and chalky after years of sun, leave it alone and mention it to us rather than rubbing at it.

The roof around the kerb counts as part of the rooflight. Moss, leaves and windblown debris collect where the kerb dams the flow on a flat roof, and a tidy margin lets water leave. Clearing it is a sweep with a soft brush and a scoop, from a safe position, with nothing pushed off into the gutter. Our note on upstand height for an opening rooflight explains why the kerb stands where it does and why the dry margin round it matters.

A seal should be soft, even and continuous, and it should touch the frame all the way round when the rooflight is shut. That is a check you can do in a minute with your eyes and one finger.

Open the unit fully, then look at the seal that runs round the sash and at the matching face on the frame. You want a clean, unbroken line. Press a fingertip on it: it should give a little and spring back. Wipe it with a damp cloth and a drop of mild soap to lift the film of grit that builds up, then dry it. Do not pick at it, and do not peel it.

Look for the following, each of which tells you something.

• Dust or grit along the seal line: the most common cause of a whistle or a tick. Wiping it away usually restores the quiet.
• A flattened or shiny stretch: the seal has taken a set. It is a sign the unit is ageing, and worth noting.
• A gap, split or lifted corner: the seal is no longer closing the line. Write down where you saw it.
• Daylight visible round the edge of a closed sash: the sash is not seating. Do not force it, and stop using the motor until we have looked at it.

The last three are not cleaning jobs. A seal that has set hard, split or shrunk has reached the end of its life, and the answer is a new sash or a new unit, not coaxing along something that has lost its spring. That is a planned job for us, and a quick photo with the date helps. Until then, a wipe and a clear channel keep an ageing seal doing as much as it can.

Silicone spray on rubber is often suggested online. Skip it unless the unit's own instructions call for it, because the wrong product can swell or stain certain seal materials, and it leaves a tacky surface that catches dust. Mild soap and water is always safe.

The rain sensor is the one part of the unit that needs to stay clean to do its job. A dirty sensor can close the rooflight for no reason, or fail to close it when it should.

Most sensors are a small panel, often on the roof near the rooflight, that senses moisture on its surface. Pollen, bird droppings, a film of dust or a sliver of leaf can make the panel misread. The routine is simple. Wipe the surface with a soft, damp cloth and let it dry. Do not use abrasive cleaners, which can scratch the sensing surface. Check that nothing overhangs it, such as a fresh branch, a satellite cable or a new piece of trim that throws a shadow or drips onto it.

A quick, safe test once it is clean: with the rooflight open, put a few drops of water on the panel from a small cup and listen. A working setup closes the sash. Dry the panel afterwards and reopen the unit from the control. How the sensor decides to close is explained in full in our guide to rain sensors on electric rooflights, and the answer to whether electric rooflights close by themselves when it rains covers what to expect.

Some installations also carry a wind or temperature sensor, a light sensor or a small receiver for a remote. Treat each the same way: keep it clean, keep it uncovered, and keep things from being stacked against it. Handheld remotes and wall panels want a wipe with a dry or barely damp cloth, and a fresh battery when the response slows. More on those in controls for electric rooflights.

You clean the outside and the control. You do not open a motor housing, lift a cover, disconnect a cable or alter any wiring. The drive is sealed for a reason, and the supply to it is a fixed installation.

Before you clean anywhere near the sash, frame or drive end, the safe habit is to make sure nobody can operate the unit while your hands are in the opening. Close it if you can, and keep the remote in your pocket rather than on the side. Two hands in a moving sash is how fingers get caught, and a motor does not recognise a hand as an obstacle in the way a person would.

Water and mains do not mix, so use a damp cloth and never a spray or a jet around a wall control, a transformer box or a junction. Use a hose on the glass, not on any housing. If a cable looks cut, chewed, scorched or loose, stop and leave it: that is one for an electrician, and our page on whether an electric rooflight needs an electrician explains where the boundary sits. The fixed supply and its protection are covered in wiring and powering an electric rooflight.

A few other gentle habits help. Keep the movement of the sash clear of furniture, plants on a sill, strings, blind cords and washing lines. Do not hang anything on the sash. If the unit has an insect screen, vacuum or brush it lightly to lift dust without pressing the mesh; our note on insect screens on electric rooflights covers what they are made from. A blind inside the well has its own cleaning routine, and fitting a blind to an electric rooflight explains how it sits.

You hear a change before you see it. A motorised unit has a settled sound when it is well, and any difference from that is worth a note.

On a calm day, open and close the rooflight once from the control and listen. A healthy unit hums quietly, moves evenly and stops with a soft meeting of seal and frame. Anything else counts as a sign.

A scrape or grind while moving can mean grit in the track, a twig in the channel or a stray object in the path. Stop, clear what you can reach by hand with the unit still, and try again. A rhythmic click often tracks the seal dragging over a dirty patch. A rattle in wind when closed usually means the sash is not being pulled fully home, or a seal has lost its spring. A buzz that goes on after the sash has stopped moving, or a sash that stops part way and will not reach the end, is for us to look at, not something to fight with the control.

It is worth knowing the normal sound of your own unit, because every make differs. For the general picture of what to expect, are electric rooflights noisy when they open and close sets out the ordinary sounds, and the page on how long an electric rooflight motor lasts explains what ageing looks like over the long run.

When you notice something, write down the date, the weather and what you heard, and take a short phone clip of the movement with the sound on. A clip from your own loft tells us more than a description does.

Here is the whole thing as one continuous pass, so you can do it without the guide in your hand. Allow ten minutes, a bucket, a soft sponge, two microfibre cloths and a soft brush.

Start inside. Open the unit on the control, check that it travels smoothly to the end of its stroke, and close it again. Put the control somewhere it cannot be pressed while you work. Wipe the inner glass with a damp cloth, then the inner frame and any blind track within reach.

Move to the seals. With the sash open, run the damp cloth round the sealing face on the sash and the frame. Press gently along it with a fingertip and note any flat, shiny or lifted stretch. Take a photo if anything looks odd.

Go outside or to your safe reach point. Rinse the glass, wash it in warm soapy water, rinse again and dry it. Clear the channels at the bottom of the frame with the soft brush and the cocktail stick, and flush with a little water to confirm it runs. Sweep the kerb margin clear. Wipe the rain sensor and move anything that shades it.

Finish with a test. Close the rooflight from the control and look round the closed sash for even contact and no daylight at the edges. Do a rain-sensor drop test if the unit has one. Reopen it, leave it as you want it, and put the remote back where it lives. That is the lot. Nothing has been taken apart, and nothing has been adjusted.

The same rooflight needs a slightly different routine over a kitchen, a loft bedroom or a stairwell, because the dirt and the noise arrive differently in each.

Over a kitchen extension the inside face clouds with cooking film and steam. Wipe the inner pane and the frame more often than the outside, and keep the opening clear of the steam from a hob. The outside gets more rain drumming across a large flat roof, so a clean channel and a clean seal matter for the sound too. See electric rooflights over a kitchen extension for how those units are laid out.

In a loft bedroom the unit is often small, pitched and near the eaves, and it sees more bird and leaf debris. Reach is the main concern, so a pole wash from the inside of the roof slope or a professional clean suits it. The room is also where small sounds matter most at night: a rattle at the seal, a tick in the channel. The routine above is the cure for most of them, and the guide to night ventilation through an opening rooflight explains how to use the opening quietly.

Over a stairwell or landing the glass is high and awkward to reach. Plan the clean around a tower, a pole or a professional visit once a year, and treat the inner face as the regular job. Electric rooflights for stairwells and landings covers those positions.

Around Crawley the practical extras are local. Trees in older neighbourhoods drop leaf and seed into channels from autumn to spring. Flat roofs near the railway and the main roads collect a film of fine dark dust that shows on the glass, and a wash with clean water lifts it without any special product. Nothing about the area changes the method; it only changes how often you will want to do it.

Care keeps a good unit good. It cannot bring back a seal that has lost its spring, a pane whose sealed unit has clouded, or a drive that no longer finishes its stroke. When those arrive, the honest move is planning a replacement.

The signs that a rooflight has moved from care to replacement are plain. There is condensation or a permanent film between the two panes of a sealed glazing unit, which a wipe will not touch because it is inside. The seals are hard, flat or split along more than one stretch. The sash no longer seats evenly, or it stops short of closing. The drive slows, stutters or stops partway more than once. Any one of these is worth noting, and a pattern of them is the answer. The sealed unit and the seals are made to last many years, but not for ever, and each one is replaced as part of a whole.

A misted pane in particular is a replacement decision, because the moisture is sealed inside the unit. Our hub on misted and failed rooflight replacement sets out how that works. If you are replacing a tired unit anyway, it is a good moment to choose the glazing for the noise the room hears, and acoustic laminated glass on an electric rooflight explains what can be specified. A replacement comes with the same written quiet spec as a new install, and the workmanship is covered by our 10-year workmanship guarantee.

If you are not sure which side of the line your unit is on, send us the photo or clip you took in the routine above. Use the quote form or message us on WhatsApp. We will tell you plainly whether it needs a wipe or a replacement.

Can I use a pressure washer on an electric rooflight?

No. A pressure jet forces water past seals and into channels, and it can strip coatings. A garden hose on a gentle setting with warm soapy water is all the glass needs.

Is it fine to clean the glass with the unit open?

Clean the inner face with the unit open and the control out of reach, and the outer face with it closed. Never put a hand or cloth into a sash that could be moved by someone else pressing the remote.

How often should the rain sensor be wiped?

Whenever you clean the glass, and again after blossom, pollen or a dusty spell. A clean sensor closes the unit when it should and leaves it alone when it should not.

Should I oil or grease anything?

No. The drive is sealed and the seals are chosen for their material, so a lubricant does more harm than good. Soap, clean water and a soft cloth are the only products the routine needs.

What if the rooflight stops moving while I am cleaning?

Leave it where it is, switch off at the fused supply if you know where it is, and read the guide to a power cut for what the unit does without supply. Then send us a short clip and we will advise.

The full range of opening units we fit sits under the electric and opening rooflight installation hub, and a quote starts with a survey where we listen to the room.