What Is Window Mesh Made Of? Materials Explained

If you've ever wondered what is window mesh made of, the answer is one of four main materials: fibreglass, polyester, stainless steel 316, or PVC-coated polyester (better known as pet mesh), each woven into a fine screen and held in an aluminium frame.

That one sentence hides a surprising amount of engineering. The material decides how clear your view is, how much breeze gets through, whether the mesh survives a cat's claws, and how it copes with Singapore's humidity. This article walks through each material in plain terms: what it's actually made from, how it's manufactured, and what it feels like to live with.

One thing this article deliberately does not do is rank them. Each material exists because it suits a different home. If you want an opinionated verdict, read our guide to the best mesh material for screens. If raw strength is your question, we've compared strength ratings in what is the strongest window mesh.

The four materials at a glance

Before the detail, here's the summary. All four meshes are fine enough to stop mosquitoes; they differ in how they handle claws, light, and airflow.

Now let's take each one apart.

Fibreglass: glass fibre in a protective coat

Fibreglass mesh starts life as molten glass, drawn into strands far thinner than a human hair. Those strands are bundled into yarn, given a protective plastic coating, and woven into a grid. The coating does two jobs: it shields the glass fibre from moisture and UV, and it bonds the mesh at every crossing point so the grid keeps its shape.

This is the classic insect screen you'll find on windows all over the world. Phifer, one of the biggest screening manufacturers globally, lists standard fibreglass insect screening at an 18×16 count: 18 strands per inch one way, 16 the other, leaving openings of roughly 1 mm. That's small enough to stop houseflies and most mosquitoes. For Singapore we prefer a tighter 20×20 to 24×24 mesh, which also blocks the smaller midges and sandflies that show up around dengue season.

Up close, fibreglass has a slightly matte, grey-black look. It softens the view a little, which sounds like a downside until you realise it doubles as mild privacy screening and a gentle sunshade. Some lower-floor homeowners pick it for exactly that reason.

Where it shines: keeping insects out on a budget while letting plenty of air through. Where it doesn't: claws. The coated glass strands snap and fray under repeated scratching, which is why we only fit fibreglass on insect-focused setups like the Base.

Polyester: the clear plastic mesh

Polyester mesh is woven from fine polyester yarn, the same family of plastic used in outdoor fabrics and sports gear. The yarn is drawn thin, woven into a tight grid, and heat-set so the mesh stays square instead of sagging over time.

The standout quality is clarity. Polyester strands can be made very fine while staying dimensionally stable, so the finished screen almost disappears when you look through it. Airflow is strong for the same reason: thin strands mean more open area per square inch.

In the hand, polyester mesh feels light and slightly silky. It doesn't have the matte shading of fibreglass, so your view and your natural light stay close to what you'd get with no screen at all.

Like fibreglass, though, plain polyester is an insects-only material. The bare yarn has no armour against claws, and a determined cat will work a hole into it. If you like polyester's qualities but have a cat, the answer is the PVC-coated version below.

Stainless steel 316: marine-grade woven wire

Stainless steel mesh is exactly what it sounds like: steel wire drawn down to a fine diameter, then woven into a grid on industrial looms, much like fabric but with metal. The result is a screen that's thin enough to see through cleanly yet far harder than any plastic mesh.

The "316" matters. It's a specific stainless steel grade that includes added molybdenum, and according to the British Stainless Steel Association, that molybdenum is what gives 316 its strong resistance to corrosion from chlorides, including salt air. It's the same grade used in marine hardware. In a hot, humid, coastal city like Singapore, that's the difference between mesh that stays bright for years and mesh that speckles with rust.

Visually, stainless steel 316 is one of the clearest options available. The wire is thin, the mesh is open, and from a couple of metres away most people can't tell it's there. Airflow is equally strong. Scratch resistance is good too: the occasional paw from a calm cat won't bother it, which is why it pairs naturally with our Core frame.

Reinforced stainless steel 316

There's a heavier-duty variant: reinforced stainless steel 316, woven from thicker-gauge wire into a denser grid. It trades some transparency and airflow (both drop to medium) for serious toughness; it withstands even pen-knife cuts. This mesh is exclusive to our boxless Sleek, where it also serves duty in rubbish chute openings and other high-abuse spots.

Pet mesh: polyester wrapped in PVC

Pet mesh is PVC-coated polyester. Each polyester strand is extruded through a coating process that seals it inside a jacket of PVC (the tough vinyl used in cable insulation and outdoor upholstery), and the coated strands are then woven and heat-fused into a grid.

The PVC jacket changes the material's character completely. Where bare polyester frays under claws, the coating lets claws slide off rather than catch, and the fused crossing points stop a small nick from running into a tear. The strands are noticeably thicker than a plain insect mesh, so the screen reads as more visible and airflow drops to medium rather than strong.

The feel is distinctive: slightly rubbery, flexible but very hard to cut or fray by hand. Like fibreglass, the darker, thicker mesh adds a mild privacy and shading effect as a side benefit.

This is the material built for cats that paw, climb, and launch themselves at windows, which is why it's the standard pairing with our heavy-duty Pro. Full details are on our pet mesh page.

The frame: aluminium housings and coatings

The mesh gets the attention, but every window mesh is really a system: mesh plus frame plus fixing. The frame side is more uniform across the industry, and ours works like this.

The structure is aluminium: light enough not to load your window, stiff enough to hold the mesh taut, and naturally corrosion-resistant thanks to the oxide layer that forms on its surface. The aluminium is finished with a baked-on coating, so the frame keeps its colour instead of chalking in the sun.

On a retractable system, the mesh rolls into a box housing at one end, with a spring mechanism handling the auto-retract. Our housings come in 4.8, 6.8, 7.8, and 8.8 cm sizes depending on the model and window span. The exception is the Sleek, which is boxless: the mesh sits in a slim track with no housing at all, built for tight recesses and windows where blinds already occupy the space.

The final ingredient is the fixing. Our standard installation is drill-free, using specialised adhesive tape and silicone rather than screws, so there's no damage to walls or windows (a relief for HDB, condo, and rental homes). One detail worth knowing: even the finest mesh only works if the install leaves zero gaps around the frame. A 5 mm gap at a grille is an open door for mosquitoes, however good the material.

The bottom line

Window mesh is made of one of four woven materials (fibreglass, polyester, stainless steel 316, or PVC-coated pet mesh) held taut in a coated aluminium frame. The plastic meshes are for insects, the steel and PVC-coated meshes also stand up to cats, and the frame and fixing matter as much as the mesh itself.

Knowing what each material is made of is half the decision. The other half is matching a material and frame to your actual home, and for that our pillar guide on how to choose window mesh in Singapore walks you through it step by step. Or skip the reading: send us a window photo on WhatsApp and we'll tell you what fits.

Frequently asked questions

Is window mesh plastic or metal?

It can be either. Fibreglass, polyester, and pet mesh are all plastic-based meshes (glass fibre or polyester, with or without a PVC coating), while stainless steel 316 mesh is woven metal wire. The frame holding any of them is almost always aluminium.

What is pet mesh actually made of?

Pet mesh is polyester yarn sealed inside a PVC coating, woven and heat-fused into a grid. The coating is what gives it its scratch resistance: claws slide off the vinyl jacket instead of catching the fibres, and the fused joints stop small nicks from spreading into tears.

Why is stainless steel mesh grade 316?

Grade 316 contains added molybdenum, which makes it strongly resistant to corrosion from chlorides such as salt air, per the British Stainless Steel Association. It's the same grade used in marine hardware, which suits Singapore's humid, coastal climate. All the stainless steel mesh we carry is 316.

Does the mesh material affect how many insects get through?

Less than you'd think. All four materials are woven finely enough to stop mosquitoes at a 20×20 to 24×24 count, so insect protection comes down to mesh density and a gap-free install rather than the material itself. Where the materials genuinely differ is scratch resistance, clarity, and airflow.

Sources

Product specifications are drawn from our own product pages and mesh types guide. External references:

1. Phifer: Standard fiberglass insect screening specifications (18×16 mesh count). phifer.com
2. British Stainless Steel Association: Composition and corrosion resistance of stainless steel grade 316, including the role of molybdenum. bssa.org.uk