Windows & Doors
Flyscreen Calculator
Calculates the flyscreen mesh area needed from your window and door opening sizes
Updated 26 June 2026 · Live
What this tool does
Calculates the total flyscreen mesh area required from the width, height and number of window or door openings, with a cut allowance.
Formula Used
Spotted something off?
Calculations or display — let us know.
People also use
How the flyscreen calculator works
This calculator multiplies each opening’s width by its height to get the net area in square metres, multiplies by the number of openings, and adds a 10% allowance for wrapping the mesh around the frame and for offcuts. Enter the opening sizes in millimetres and the calculator returns the total mesh area required.
Measuring window and door openings
Measure the clear opening the screen will cover, not the glass. Fixed flyscreens fit the outside of the reveal; retractable and sliding screens follow the track length. If you are screening sliding doors, measure the full panel travel so the mesh covers the open position.
Mesh types
Standard fibreglass mesh suits most homes. Aluminium and pet-resistant meshes are heavier and may need a wider frame allowance. In bushfire-prone areas a separate ember-rated steel mesh is required for vents and weepholes — use the ember guard mesh calculator for that, as the aperture rules differ.
What this tool does not do
It estimates mesh area only. It does not size the frame sections, spline or fixings, and it is not a substitute for a supplier measure-and-quote on made-to-measure screens. Always confirm openings on site before ordering.
Adjusting the defaults
Every input is editable. Enter your own opening sizes and count, and the mesh area recalculates instantly. Add more openings of different sizes by running the calculator for each size group and summing the results.
On-site considerations
Order a little extra mesh on rolls so a single piece spans the widest opening without a join — joins in flyscreen mesh are visible and weaken the panel. Keep the mesh square to the frame as you spline it; a skewed weave shows badly in raking light. For doors that see heavy use, a tighter, heavier mesh resists pushing-out better than economy fibreglass.
Using this alongside other BuildMetricLab tools
Pair this with the window area and window sill calculators when you are pricing a whole window package, and with the material cost calculator to add the framing and spline. Every BuildMetricLab tool runs entirely in your browser — no sign-up, no data sent anywhere, and every formula is shown on-page so you can audit the maths.
Sources & methodology
Calculates flyscreen mesh area as opening width × height (converted from millimetres to square metres), multiplied by the number of openings, with a 10% allowance for frame wrap and offcuts. Every result is calculated from the values you enter, and all inputs are editable.
Frequently asked questions
Are flyscreen calculator results accurate enough to order mesh?
Use them as a starting estimate only. Verifying the final quantity with your supplier or contractor before ordering is good practice — site conditions, wastage and cut-offs all affect the true figure.
What wastage percentage should I use?
The calculator defaults to the typical Australian trade allowance for windows & doors. Increase it for complex cuts, awkward shapes, or first-time DIY. The default wastage allowance reflects common trade practice; values lower than the default may underestimate offcuts.
Does this replace professional advice?
No. This tool is a planning estimator. For works that affect structure, the National Construction Code (NCC), boundary or dividing-fence, gas, electrics, drainage to a sewer, or similar, consult a suitably qualified professional.
Can I change the unit prices?
Yes — every price field is editable. Plug in your supplier's quote to get a total that matches your project.
Related tools
Calculators from other categories that planners often reach for next.