Rectangular Bed Net (Mosquito Net) Netting Area, Mass & Order Quantity

The formula

This is the expression the tool evaluates. Every term is named underneath, with the unit it must be supplied in.

How the result is derived

Step by step, from the values you type to the figure on screen.

1. The 8 inputs are read from the form on every keystroke: Length, Width, Height, Border Height at the Bottom, Netting Mass per m², Seam, Hem & Cutting Allowance, Netting Roll Width and Nets in the Order.
2. Each value is checked against the accepted range in the input table below. A value outside its range stops the calculation rather than producing a misleading figure — the results blank out and a message appears.
3. The validated values are substituted into the expression above, which resolves Netting per Net, incl. Allowance together with every supporting figure in one pass — no value is carried over from a previous entry.
4. The supporting outputs — Side Panels (Netting), Roof Panel, Netting Area as Made, Border Fabric per Net, Netting Mass per Net, Netting for the Order, Netting Roll Metres for the Order and Netting Mass for the Order — come from the same pass, so they always describe the same case as the headline figure.
5. Results are rounded for display only. The full-precision value is used throughout the chain, so reading a rounded intermediate figure back into the tool by hand can shift the last digit.

What each input means

Where to read each value on the floor, the unit it must be in, and the range the tool accepts.

What the tool returns

The headline figure and every supporting value it is built from.

Worked example

Substituting

A 25 cm border on the same net takes 1.70 m² of netting off the sides and puts 1.70 m² of border fabric on instead, which can weigh several times the netting it replaces.

How to use it

1. Work through the input groups in order — Net Size and Netting & Order. The defaults are a realistic case, so you can change one value at a time and watch what moves.
2. There is no calculate button. Every figure recalculates as you type or drag, which is what makes this usable for a what-if sweep rather than a single answer.
3. Read Netting per Net, incl. Allowance in the dark results panel — that is the headline figure, expressed in m².
4. Check the supporting rows underneath (Side Panels (Netting), Roof Panel, Netting Area as Made, Border Fabric per Net, Netting Mass per Net, Netting for the Order, Netting Roll Metres for the Order and Netting Mass for the Order) before acting on the headline — they are where an implausible input usually shows itself first.
5. Reset to defaults returns every field to the reference case, which is the quickest way to check whether a surprising result came from the tool or from an input you had changed earlier.

Where this is used

• Process planning — establishing Netting per Net, incl. Allowance before a trial is booked, so machine time and material in Nonwovens & Technical Textiles are committed against a calculated figure rather than an estimate.
• Costing and quotation — Netting per Net, incl. Allowance is an input to the cost sheet, and quoting from a worked number rather than a remembered one is what keeps a margin intact.
• Troubleshooting — when the floor result drifts from plan, entering the measured values (starting with Length) shows how much of the gap in Netting per Net, incl. Allowance each variable explains.
• Teaching and study — the accepted ranges bracket normal Nonwovens & Technical Textiles practice, so moving one variable at a time shows the shape of the relationship rather than a single answer.

Reading the result

Typical bands and what each one is telling you.

Assumptions and limits

• The net is treated as an open-bottomed box: four side panels the full height, less any solid border, and one roof panel. Hanging loops, the door overlap of some designs and packaging are not netting and are left out; the seam and cutting allowance covers seams, hems and cutting loss together and comes from the cutting room. Netting gsm is the maker's figure for the finished netting; an insecticide treatment or coating is part of it if the gsm was measured after treatment. Roll metres assume every panel is cut from a roll of the width entered with the allowance covering the nesting loss. **This is a material take-off; it does not grade the netting for strength, mesh count or insecticide content, which tender specifications set separately.**
• Every input is bounded to the range normal practice occupies (Length 50 to 400 cm, Width 50 to 400 cm and Height 50 to 300 cm, and so on for the rest). Those bounds are guard rails against typing errors, not a claim that the formula fails one unit outside them.
• The calculation is deterministic: the same inputs always give the same result. It carries no allowance for machine condition, operator skill, ambient conditions or lot-to-lot material variation unless an input above explicitly represents one.
• Nothing is sent anywhere. The maths runs in your browser, so the numbers you type never leave the page.

Standards and further reading

• The procurement or tender specification: net size, netting yarn, mesh and bursting strength are set there, not by this tool.
• ISO 13938-2, bursting strength of textiles by the pneumatic method, used in many bed-net specifications.
• ISO 3801, determination of mass per unit length and mass per unit area, for the netting gsm.

Questions people ask