The short answer
Not as standard on every model, but a screen is available for many of them. Several roof window makers offer an insect screen as an accessory, fitted to the frame or built into a blind, and some flat rooflights and lantern vents can take a mesh across the opening. If you want to leave a rooflight open on a summer evening without letting in wasps and moths, ask for the screen when you choose the window.
It is easier to specify at the start than to add later, because the screen has to fit the frame, the lining and the sash action. A screen that clashes with any of them ends up fixed badly or left in a drawer.
How the screens are made
There are two main designs, and which one you get depends on the rooflight.
- Mesh blind
- A fine mesh runs in side channels on the window, like a blind that pulls down from the top of the sash. VELUX offers this type for its roof windows. It is raised out of sight when not wanted and pulled down when you open the window. You can fit it with, or instead of, a darkening or pleated blind.
- Fixed or frame screen
- A mesh panel in a light frame fixes over the opening, either on the outside of the kerb or inside the vent. This is more common on flat rooflights, lanterns and larger ventilation units, where the opening is a hinged lid or a side vent. It is usually a simple fixed panel, so it stays in place whether the vent is open or closed.
Both do the same job. Which suits you depends on whether you want to see the mesh, whether you can reach the window easily, and how the sash opens.
Does a screen cut the airflow?
A little, yes. Fine mesh adds resistance, so the same opening moves a little less air than a bare one. For most rooms the difference is not noticeable, and it is a fair trade for keeping insects out. It matters more in a small bathroom or a hot loft, where the aim is to push air out quickly, and a very fine mesh can slow that down.
The screen also shades the glass a touch and can slightly soften the daylight coming through. A mesh blind can be raised out of the way when the window is shut, which is one reason it suits bedrooms and landings.
Fitting and finishing
Screens bring a few practical questions.
- Does the mesh channel or blind cassette fit inside the lining, or does it need extra depth?
- Does the sash still open to the angle you want with the screen in place?
- Can you reach the pull handle from the floor, or does it need a pole or a motor?
- If the window is electric, can the screen be raised and lowered electrically too?
A mesh blind sits in the same space as other fittings, so it can reduce the clear gap when open. That matters if the window also serves as an escape route from a loft room, so the question belongs in the opening distance discussion as well. A screen should never be fixed over a window intended as the way out.
We record the screen on the finish schedule alongside the lining and the finish, so the depth, the side channels and any cable are planned before the ceiling is cut. A screen that needs a power feed is far easier to wire while the plaster is open than after it has been decorated.
When a screen is worth having
The case is strongest where you want a window open for long periods.
A kitchen or a bedroom under the roof can get warm, and an opening rooflight is a good way to let heat out overnight. That is also when moths come to the light. A screen makes the open window usable at night. The same is true of a bathroom with a roof window that you leave ajar to clear steam, or of a conservatory-style lantern over a dining table in summer.
It matters less on a rooflight that is mostly kept shut, such as a fixed unit, or one used only for a short burst of ventilation. Our guide to opening rooflights for ventilation and cooling covers when it is worth opening one at all.
Keeping a screen clean and working
A mesh collects dust, pollen and the odd cobweb, particularly in a loft room where air moves slowly. A soft brush or a vacuum with a brush head, run lightly across the mesh a couple of times a year, keeps it clear. Avoid pressing hard, since fine mesh dents and stretches, and avoid strong cleaners that can damage the edge seals.
Because the screen is usually a moving part, it is worth running it up and down when you do the seasonal clean, to check it runs square in its channels and does not catch on the lining. If a mesh blind is fitted behind a motorised window, test it with the sash both open and shut.
A screen should not be used as a safety barrier. It keeps insects out, but it will not stop a child or a pet falling against an open sash, and it is not a substitute for a sensible opening restrictor on a low window.
What to ask before you order
Ask whether a screen is offered for the exact model, whether it is a mesh blind or a fixed panel, and what it adds to the depth and the cost. Ask whether it can be added later or is better fitted with the window. If you are replacing an existing rooflight, tell us at the survey, because the old frame may not match a newer screen.
To compare the options for your room, see our electric opening rooflights page, or ask for a quote and we will confirm what is available for the unit you want.