Fly screen for a sliding patio door: which solution for a wide opening?
Camille VidalIn short: for a sliding patio door, the simplest solution is a made-to-measure magnetic fly screen with several panels, fitted without drilling onto the frame. It covers the full width, you walk through it one-handed and it closes itself behind you. Plan on one panel per 100 to 120 cm of width, about ten minutes to fit with no tools, and a price of $199.99 to $859.99 depending on the dimensions. Pleated and roller screens exist too, but they involve a floor track and a technical installation.
Let's look at why a patio door deserves different treatment from a window, and how to choose without getting the format wrong.
Why a sliding patio door is a case of its own
We tend to think of it as a window, only bigger. That is exactly the mistake: three constraints specific to wide openings change everything.
The width, first
A window is 60 to 120 cm. A patio door starts at 180 cm and often goes past 300 cm, sometimes 400 on newer builds. At that scale, a single sheet of mesh starts to ripple, to slap in the slightest draught and to gape at the edges. The answer is not to pull it tighter, it is to break the width into several panels with magnetic dividers.
The daily traffic, next
A patio door is not an opening you crack open in the evening: it is the way to the terrace, used by the whole family, often with your arms full of a tray or a chair. A system you have to open and then close by hand gets abandoned within three days. It is the most underrated criterion when choosing, and the one that decides whether the screen actually gets used.
The floor track, finally
Sliding doors have a low track, sometimes a raised threshold. Not every solution copes with it: some actually require you to add another rail, which creates an obstacle underfoot and makes cleaning harder. A solution that fixes only to the frame, at the top and on the sides, leaves the threshold clear.
The possible solutions, compared
Four families share the wide-opening market. Here is what each one brings, and what it asks in return.
| Solution | Width covered | Fitting | Walking through | What you accept |
|---|---|---|---|---|
| Made-to-measure magnetic, multi-panel | Up to very wide openings | No drilling, ~10 min | One-handed, self-closing | Visible mesh, designed for daily use |
| Pleated on a track | Wide openings | Floor track, technical fit | Open and close by hand | A track underfoot and a higher budget |
| Side roller | Wide openings | Screwed cassette, technical fit | Pull across and release | Drilling the frame, a mechanism to maintain |
| Strip curtain | All | Very simple | Free | Poor seal: the strips let insects through |
The strip curtain is the classic false good idea: it costs little and goes up in five minutes, but the strips never meet perfectly and mosquitoes end up getting in. Pleated and roller screens are genuine solutions, sturdy ones, but they involve a small building job and rarely close on their own. Multi-panel magnetic is the one that ticks the wide opening, the no-drilling fit and the free passage all at once, which is why it dominates on patio doors.
How many panels for my width?
This is the question that comes up most, and the answer is simple: you add a magnetic divider roughly every 100 to 120 cm. Each divider holds the mesh in place and stops it ballooning in the wind, while creating an extra point to walk through.
- Up to 120 cm: a single panel is enough, as on a standard door.
- 120 to 240 cm: two panels with a central divider. This is the most common format on a two-leaf patio door.
- 240 to 360 cm: three panels, two dividers. This is what a three-leaf door needs.
- Beyond 360 cm: four panels or more, to be confirmed against the configuration.
One detail that matters: the divider does not have to sit in the middle. On a door where you always pass on the same side, it is better to line an opening up with the leaf you actually slide day to day, so you never have to part two panels at once.
See the large-opening fly screen
No drilling: what it changes on a patio door
On a window, drilling remains an option. On a patio door it is another matter: the frames are often thermally broken aluminium or reinforced PVC, and a badly placed hole can compromise the seal or the joinery warranty. Not to mention that if you rent, the question does not even arise.
A magnetic fly screen attaches to a self-adhesive hook-and-loop strip fitted to the frame: no holes, no screws, no marks when it comes off. Fitting takes about ten minutes with no tools, and the threshold stays completely clear since nothing is fixed to the floor. The step-by-step is in our installation guide.
One point to watch, though: the adhesive needs a clean, dry and flat surface. On a south-facing door, degrease the frame carefully before fitting and let the strip settle for a few hours before hanging the mesh.
The mesh: what separates a screen that holds from one that gives up
On a wide opening the mesh works much harder than on a window: more surface exposed to the wind, more handling, more sun. That is where the difference in material shows up fast.
Our fly screens use a coated E-glass fibreglass mesh, woven at 18 × 16 threads per inch. It does not rust, does not deform and stays supple, which is exactly what a magnetic system needs. It is flame retardant (M2 rating), UV treated so it does not yellow season after season, and rated for 8 to 20 years. You still see the terrace through it, and the air moves normally.
By contrast, the thin polyester used in budget kits slackens within the first season on a wide span, and a slack panel on a patio door is a panel that gapes at the bottom.
Measuring a patio door properly
A badly measured patio door does not forgive: over 300 cm, two centimetres out is visible. A few precautions are enough.
Measure the total width of the frame, from one upright to the other, then the height from the top of the frame down to the floor. On a wide opening, take each measurement in three places, at the top, in the middle and at the bottom for the width: wide doors are rarely perfectly square, and it is the narrowest point that counts. Also check that the bonding area is flat all the way round, with no proud seal or rounded corner that would stop the strip adhering.
If you are between two values, take the larger one. Our sizing guide details the method model by model, and the configurator works out the number of panels from your width on its own.
How much does a patio door fly screen cost?
A made-to-measure large-opening fly screen runs from $199.99 to $859.99 depending on the width and the number of panels needed. That is more than a window screen, quite simply because there is more mesh, more magnets and one or more dividers to build in.
The good news: made to measure costs no more than the equivalent standard format here, delivery is free, and the volume discount kicks in from the second screen (-10 %, then -20 % from four). If you fit out the patio door and the windows of the same room, the bill drops accordingly. The full breakdown is in our price guide.
Frequently asked questions
Which fly screen for a sliding patio door?
A made-to-measure magnetic screen with several panels. It covers the full width of the frame, fits without drilling and closes itself behind you, which is decisive on a doorway used several times a day.
How many panels for a 3 metre patio door?
Three panels, with two magnetic dividers. Count roughly one divider every 100 to 120 cm: it stops the mesh ballooning in the wind and creates an extra point to walk through.
Can a patio door fly screen be fitted without drilling?
Yes. The mesh attaches to a self-adhesive hook-and-loop strip stuck to the frame, with no screws or holes, and comes off cleanly. It is the option to favour on aluminium or PVC joinery, and the only one available if you rent.
Does the screen get in the way of the sliding track?
No, not with a magnetic model: nothing is fixed to the floor, everything holds on the frame. The threshold stays clear, the door slides normally and cleaning the track is not obstructed.
What if my patio door is more than 4 metres wide?
That works in four panels or more. Beyond that width the configuration is worth confirming case by case: go through the configurator, which works out the number of dividers from your exact dimensions.
Does a patio door screen stand up to wind?
The magnetic dividers are there precisely for that: they break up the surface and stop the mesh acting like a sail. On a very exposed terrace, add an extra divider rather than pulling the mesh tighter.
Find yours in 2 minutes
Measure your patio door, enter the width and the height, and the configurator works out the number of panels and your exact price: build your made-to-measure fly screen →