This page gathers what the health departments and Queensland’s regulation say about keeping a screen in working order, and arranges it by when to look.
What a sound screen looks like
For the screens on a house, the official test is short. healthdirect asks that insect screens have no tears or holes. Queensland asks that they be in good condition, with no visible damage. Victoria’s checklist says to maintain fly screens on windows, doors, vents and chimneys, at a mesh no coarser than 1.2 mm.
WA Health adds one more test where biting midges live: whether the mesh is fine enough at all, since midges can fit through standard fly screens. And for March flies, its advice for houses and workplaces is that insect screens are installed and in good condition.
None of the official pages read for this guide gives a method for patching or re-meshing a window screen. For a particular product, the maker’s own instructions are the place to look.
How often, by whose advice
The timetables in the official sources are about tank screens and the tank around them. Set out by interval, they make a calendar.
| When | What | Whose advice |
|---|---|---|
| After rainfall | Open and clean the first-flush device on a tank’s downpipe. | Victoria |
| Weekly | Check around the home for mosquitoes or larvae, including the screens and seals on rainwater tanks. | Queensland |
| Every three months | Check a tank’s first-flush diverters, and look for water pooling around the tank. | Victoria |
| Every six months | Check the tank’s mosquito-proof mesh for holes or defects. | Victoria |
| At least once a year | Inspect the screens on tank inlets and overflows, to make sure they are still sealed and undamaged. | New South Wales |
| Regularly | Clean all tank screens; check that inlet and overflow screens are secure, in good condition and clean. | New South Wales and Victoria |
| Always | Keep a Queensland tank’s screens or flap valves meeting the regulation; take one off only for maintenance, and put it back immediately after. | Queensland (law) |
What a screen is made of
Brass, copper, aluminium or stainless steel gauze, with a mesh size of not more than 1 mm, installed in a way that does not cause or accelerate corrosion, and stopping mosquitoes passing through. A flap valve that stops mosquitoes when closed is the alternative.
Brass, copper, aluminium or bronze wire, no coarser than a 1–1.5 mm gap per hole, with plastic mesh acceptable for removable mesh. Plastic or steel mesh can also go around pipes, valves and access points.
Queensland’s rule covers how the gauze is fixed as well as what it is made of: it must be installed in a way that does not cause or accelerate corrosion.
Sprays on screens, and cleaning around them
WA Health says residual chemical sprays can be applied to places where biting midges rest, insect screens among them, to help reduce adult numbers. Its cautions come with it, and they belong together:
- some residual sprays can control midges for up to six weeks, depending on conditions;
- using residual sprays again and again can harm other insects and spiders;
- read the label every time, and follow the manufacturer’s instructions for applying it.
For cleaning around the home generally, WA Health suggests chemical-free products such as hot soapy water or vinegar, a cream cleaner rather than a spray for stubborn stains, and opening windows and doors whenever chemical cleaners and sprays are used, following their instructions.
When a screen comes off, and when a tank is retired
In Queensland, it is an offence to destroy, damage or take off a mosquito-proof screen or flap valve fitted to a tank. The one exception is taking it off to carry out maintenance, and then it must be put back immediately after the maintenance is finished. NSW Health’s advice is to check for and repair any holes or gaps in a tank that could let mosquitoes in.
A tank that is no longer used is its own risk. Victoria’s Department of Health says degraded or unused tanks can hold pools of water with openings for mosquitoes to breed, and that when a tank is no longer needed it should be professionally drained, cut up and taken to an appropriate waste disposal facility, with the local council as the place to ask.
A screen kept on this calendar is ready for the job the health departments give it, keeping mosquitoes out. For where each screen goes, see fighting the bite at home and screens on rainwater tanks.