Which insect mesh actually keeps the bites out of a Wollongong house?

Most people buy flyscreens as though insects were one problem. They are several. A mosquito, a house fly, a moth drawn to a lamp and a biting midge differ in size and habits, and a mesh that is perfect against one can be useless against another. The good news is that the choice is small: a handful of mesh types, each with a clear job. The trick is matching them to the right windows.

Work out what is biting before you buy mesh

NSW Health includes screening as part of mosquito-bite prevention. That advice does not certify every product sold as standard mesh. Ask what the selected product is intended to exclude, how it fits the frame and which other openings remain unprotected. Inspect visible tears and gaps from a safe position. Keep health advice separate from a supplier's product claim, and use the current NSW Health guidance for personal protection rather than relying on screens as the only measure.

HealthyWA advises that biting midges can pass through standard flyscreens and recommends fine mesh on doors and windows. However, unseen insects and itchy bites on a calm evening are not enough to identify a species. Record what you have observed, including whether an insect was actually seen indoors, and seek advice from a pest professional or local environmental health service when uncertain. Do not commission an entire mesh change on the assumption that every dusk bite is a midge bite.

Larger insects inside can prompt a fit and use check, but they do not prove that the mesh itself has failed. An open door, another entry route or a gap around the frame may be involved. Different insects and life stages also vary in size. Record the opening and the observed route if possible rather than assuming any intact mesh excludes every insect. Ask the supplier to assess the complete screen, including its perimeter, instead of replacing fabric alone without investigating the problem.

The mesh types compared

Mesh counts and aperture sizes are described differently by different suppliers, so do not compare a number from one brochure with a number from another. If midges are the reason you are buying, ask the supplier to state on the quote that the mesh offered is a fine or midge mesh, and what its opening size is.

The airflow trade-off, and how to manage it

Airflow depends on the open area of the mesh, the strand dimensions and weave, as well as the whole opening. A smaller aperture does not by itself establish how two different products compare. Ask for aperture and open-area information for each sample, using matching units, and check any available test information. View the samples in the intended position and light. A darker-looking sample or a thicker strand is not a reliable substitute for airflow data, particularly when comparing different materials and constructions.

Plan screening across the routes insects could use, not simply the window beside the person being bitten. If confirmed midges are the concern, fitting fine mesh to one bedroom while another connected opening remains unsuitable may leave an entry route. Compare the household's ventilation pattern, including doors between rooms. HealthyWA also notes that air circulation may discourage midges from biting; it is not proof that a particular room is protected. Decide any staged work with these remaining routes made explicit rather than assuming untreated rooms cannot affect the result.

Keep any chemical-control decision separate from the mesh order. Ask an appropriate pest professional about the identified insect and the setting if physical screening does not address the problem. Do not apply a spray to a mesh because another product's brochure suggests it: the chemical label, permitted use and screen manufacturer's material-care requirements all matter. A supplier should be able to discuss the screen without prescribing a treatment from a brief description of bites. Avoid using a temporary treatment as evidence that a chosen aperture is suitable.

Salt air and sun: record actual exposure

Coastal exposure is a condition to describe, not a material selector based on kilometres. Note direct spray, visible deposits, shelter and which face of the building is involved. Compare the exact mesh material, coating and frame components with the manufacturer's approved environment and care requirements. Fibreglass, aluminium and stainless products each have specifications that cannot be reduced to one universal lifespan. Ask what inspection or cleaning is needed and whether replacement material will remain available. A more expensive material does not remove the need to assess the complete assembly.

A re-meshing quote should address the frame as well as the fabric. Photograph damaged corners, loose retaining material and visible corrosion without dismantling the screen. Ask whether the existing channel and frame can retain the proposed mesh, especially if it has a different strand thickness. Keep repair and replacement options itemised so the reason for a new frame is clear. The flyscreen service page covers the enquiry route; your opening record can identify which frames need inspection before a material is selected.

Assess mesh and perimeter fit together

Even an appropriate aperture cannot resolve an opening around the edge of the screen. Record visible gaps at frame corners, loose mesh edges and the meeting points of a sliding door. Avoid labelling a mesh or room midge-proof from appearance alone. Ask how the proposed screen will close the relevant perimeter while preserving drainage, ventilation and normal window operation. If a gap changes as the window moves, record that movement for the installer rather than filling the space yourself with an improvised seal.

Daylight or a torch can help reveal some visible gaps from a safe standing position. Neither method shows every entry route or verifies exclusion performance. A sliding screen that is uneven may have a roller, track, frame or installation issue; appearance alone does not identify the repair. Photograph what you can see and describe whether the door drags, lifts or will not latch. Avoid lifting a heavy screen out to investigate unless its instructions permit that task and it can be done safely.

Doors: the screen that is left open

Door use belongs in the mesh discussion. An opening left unscreened while items are carried outside is a different problem from an unsuitable aperture. Record which door is used most, whether it closes after each trip and whether the current screen is awkward enough that people leave it open. A closing mechanism may help in some configurations, but it needs to suit the product and household. The assessment should include the effort and sequence of operation, not just a mesh sample held against the light.

For a busy back door, compare the proposed screen with a realistic trip carrying shopping or washing. Check where a person stands to open it, whether the grip is reachable and whether the screen interferes with the main door. Large deck openings may need a different arrangement, as the bi-fold screen guide explains. If an insect requirement applies throughout a connected space, include these doors in the assessment alongside bedroom windows. A convenient screen is more likely to be used consistently, but convenience does not establish exclusion performance.

Keeping fine mesh clear

Dust and deposits can affect a screen's appearance and operation. Use the care instructions for the exact mesh, coating, frame and moving components. Ask whether brushing, vacuuming, rinsing or removal is permitted and what tools should be avoided. Do not assume a hose is suitable for every assembly or that a fixed seasonal schedule fits all exposure. Plan how the screen can be reached safely; high windows may require a service arrangement. Keep any model reference and care sheet so the next person cleaning it does not have to guess.

Where to spend first

If the work must be staged, first list known defects and unresolved insect identification. Ask for separate costs for repairing damaged screens, restoring perimeter fit and changing the mesh specification. Then choose stages with the unaddressed openings clearly recorded. A bedroom priority may make sense to a household, but it does not guarantee that insects cannot enter through another room. Keep the product reference for each completed opening so a later order can match its aperture and appearance. Review the result before repeating the same specification throughout the house.

Room-by-room mesh planner

Add one record per opening, including observations and requirements. The saved list contains questions for the supplier; it does not identify insects or select a material from distance alone. Changing the current entry does not edit a saved row. Add the next record or clear the list and rebuild it if a saved record is wrong. The download contains saved rows only.

Hypothetical example: a house near a lagoon

Hypothetical example

A brick house in the northern suburbs sits a short walk from a lagoon mouth and about a kilometre from the beach. It has old aluminium-framed flyscreens with aluminium insect mesh, some of it powdery. The owners get bitten in the main bedroom on still summer evenings with the windows shut behind the screens, and they have a dog that leans on the laundry door screen.

The owners record the bites without assigning a species from the time of day. They ask for help identifying the insect and for an inspection of the bedroom screens and connected openings. The laundry record separately notes pet pressure, because stronger strands do not guarantee containment or a suitable insect aperture. Visible deterioration prompts a frame-and-mesh assessment rather than an automatic material substitution. They obtain samples and model references before deciding which openings to tackle first, and keep the unanswered questions alongside the staged quote.

Mistakes and remedies

For a large opening, mesh selection and hardware feasibility need to be resolved together. Check the product-specific mesh choices for bi-fold and French-door arrangements before assuming a sample can be fitted to either system. Where security is required, ask about the complete tested assembly and the effects of changing its mesh. The word security does not establish a particular insect aperture, and changing fabric can affect the assembly's intended performance.

Mesh questions