Fly screen for a roof window or Velux: the made-to-measure solution, no drilling

Yes, there is a fly screen (also called an insect screen) that genuinely suits a roof window, a Velux as much as any other make, and it is not a separate product: it is exactly the same made-to-measure fly screen we make for your windows and doors, simply configured with hook-and-loop fastening rather than magnets. A panel made to the millimetre, fitted on the inner frame of the window with no drilling, and lifted off in seconds whenever you need to work the sash. It is the simplest answer to a problem every converted loft knows: sleeping with the window open without being bitten is impossible. Let us look at why these rooms are the worst affected, why off-the-shelf screens fall short, and how to kit out your roof window in about ten minutes.

One clarification before we start: Velux is a brand of roof window, the best known in Britain, but not the only one (Roto, Fakro and Keylite sit in plenty of roofs too). So when people search for a Velux fly screen, what they are really after is a fly screen for their roof window. Everything that follows applies to your window, whatever the make.

Why loft rooms get bitten the most

If you feel the mosquitoes are targeting your loft bedroom rather than the rest of the house, you are not imagining it. Three factors stack up under a roof.

Heat, first of all. Warm air rises and gathers under the roof: these are the hardest rooms in the house to keep cool. In summer the only real answer is to open the roof window in the evening and leave it open all night to let out the heat stored during the day. A wide opening, all night long, in the very room where you sleep: it is hard to be more welcoming than that.

Light, next. A bedside lamp or a reading light behind a roof window can be seen from a long way off: nothing overlooking you, no hedge, nothing at all between your window and the night sky.

And finally, you. The CO2 you breathe out while you sleep and the warmth of your body guide mosquitoes straight to your pillow. A room occupied all night, with the window open, ticks every box. We go into these mechanisms in our article on what attracts mosquitoes.

Faced with all that, plug-in diffusers and insecticide sprays are a false good idea: filling the room you sleep in with chemicals while leaving open the very window that disperses them makes very little sense. The real answer is mechanical: close the way in to mosquitoes while letting the air keep moving.

Why an off-the-shelf fly screen does not work on a roof window

The first instinct is usually to look for a ready-made fly screen at the DIY shop. On a roof window that runs into trouble quickly, for three reasons.

Sizes that vary enormously

There is no such thing as one size of roof window: the dimensions change with the brand, the model, the year it was made and the format chosen when it was fitted. An off-the-shelf screen will therefore almost always be too small (gaps left down the sides, so you may as well fit nothing) or too big (creases, a rippling panel, a fixing that peels away).

A sloping frame, often lined

A roof window sits within the thickness of the roof, with an internal lining that follows the pitch. Rigid screw-in frames, designed for vertical windows, adapt badly to it, and the roller fly screens sold for roof windows generally require drilling into the frame or the lining. Drilling the timber or the PVC of a roof window marks it for good: a decision an owner hesitates over, and one a tenant simply cannot take.

A window you still need to operate

The last point is the most important: a roof window is operated by a control bar or a handle on the sash itself. A fixed screen that blocks access to it forces you to choose between fresh air and protection. That makes no sense, since night time with the window open is precisely when the fly screen should be doing its job.

The answer: the same made-to-measure fly screen, with hook-and-loop fastening

The right approach turns out to be very simple: treat the roof window as what it is, a window. Our made-to-measure fly screen for windows sits flat against the inner frame, on the room side: an adhesive strip goes right around the frame, and the panel attaches to it. No drilling, no tools, about ten minutes to fit.

The mesh is E-glass fibreglass, woven at 18×16 threads per inch and fire-rated M2: tight enough to stop mosquitoes, tiger mosquito included, open enough to let the air through and the light in. You sleep with the window open, the room breathes, the mosquitoes stay on the roof.

Why hook-and-loop rather than magnets on a roof window

This is the real difference from an ordinary window. On a wall the panel hangs vertically and magnets hold it perfectly. On a Velux it lies at an angle, sometimes almost horizontally above your head, and its own weight pulls downwards all the time. Hook-and-loop tape, by contrast, grips the strip all the way around and does not let go: it is the most reliable fixing over time for a sloped or under-eaves fit, all the more so as a roof window is rarely opened wide.

That is why the configurator steers roof windows towards hook-and-loop fastening, and why this configuration goes through the made-to-measure configurator: hook-and-loop is not offered on the standard models in the shop, and only the made-to-measure route lets you choose it. Magnetic fastening remains the reference option for vertical windows and doors in classic sizes.

The decisive point for a roof window is the made-to-measure side of things. Every panel is made to the millimetre in our workshop in Montpellier, within 6 to 9 working days, exactly to the dimensions of your frame. No creases, no slack, no trimming with a craft knife. And the screen comes off and goes back on in seconds: you peel back one side, work the window, then press the panel into place again. At the end of the season you can take it off completely, without leaving a mark.

So for a roof window, everything happens in the configurator: configure your made-to-measure fly screen online, choose the Velux application, enter your dimensions to the millimetre, and it will steer you towards the 4-sided hook-and-loop fixing suited to your fit. Production then starts in the workshop.

How to measure a roof window, step by step

Measuring decides everything, and it is simpler than you might think.

1. Identify the mounting surface

The fly screen fixes to the inner frame of the window: the fixed surround you see from inside the room, around the sash that opens. That flat surface, in timber or PVC, is what takes the adhesive strip. Check that it is clear all the way around, with no handle or blind overhanging it.

2. Measure the width and the height to the millimetre

Measure the width, then the height of the area to be covered, taking each dimension at two or three points (top, middle, bottom): frames are not always perfectly true. Note your measurements in millimetres, without rounding. Our measuring guide shows exactly where to place the tape for your configuration, and tells you which figure to keep if two readings differ.

3. Use the data plate as a cross-check

On most roof windows a data plate is visible at the top of the window once you open the sash. It gives the model and the size code, and therefore the original dimensions of the window. It is a useful cross-check for your measurements, but never order on the strength of a code alone: two windows identical on paper can have different internal linings depending on the finish and the installation. What counts is the actual measurement of your inner frame, to the millimetre.

Special cases: centre-pivot, top-hung, roller shutter

Centre-pivot or top-hung: both work

A centre-pivot window turns on a central axis: the top of the sash tilts inwards while the bottom swings outwards. A top-hung window, by contrast, opens fully outwards. In both cases the inner frame stays exactly where it is, and it is the inner frame that carries the fly screen.

With a top-hung window the sash goes entirely outside: the window can stay wide open all night behind the screen. With a centre-pivot window the top of the sash swings inwards: in a normal ventilation position it usually stays within the depth of the reveal and never touches the panel; for a wide opening or a full rotation, to clean the glass for instance, unhook the panel for a moment and press it back with one movement.

External roller shutter: no interference

A roller shutter, an awning blind or a heat-reducing blind fitted on the outside of the window: no problem at all. The fly screen is entirely on the inside, so the two never meet. You can close the shutter in the evening with the screen still in place, and combine darkness, coolness and protection.

One thing to watch: internal blinds, pleated or blackout, that run in side channels fixed to the frame. In that case, measure the flat surface available around the channels, or move the fitting out onto the surround of the internal lining. The measuring guide covers this situation.

Fitting it in 4 steps

On the day your fly screen arrives, set aside about ten minutes, a clean cloth and nothing else.

1. Clean around the frame. The surface must be clean, dry and free of grease so the adhesive bonds for the long term.
2. Stick down the adhesive strip (magnetic or hook-and-loop) around the frame, starting from one corner, without stretching it.
3. Position the panel from the top down. It presses onto the strip; work your way down, adjusting as you go, without pulling it too tight.
4. Check the whole perimeter. Press all the way round to bed the panel down, and make sure no gap is left in the corners.

The slope of the window makes nothing more complicated: the panel is very light and the hook-and-loop tape holds it all the way around, not just at the top. To picture each step, our installation guide goes through the fitting in detail.

One last tip: if several rooms in the loft are affected, kit them out in a single order, as the discount applies automatically: -10% from 2 items, -20% from 4. Ready to sleep with the window open? Configure your made-to-measure roof window fly screen: two measurements, a few clicks, and your panel is made to the millimetre in the workshop.

Frequently asked questions