Greenhouse Film Cost per Square Metre (and per Season): How to Compare Quotes

Q: How do I convert a per-kilo film price to cost per square metre?

Multiply price per kg by area weight: thickness in mic x ~0.92 g/m2 per mic. A 12 USD/kg quote for 150 mic film is about 1.66 USD/m2, then divide by rated seasons of life.

Q: Why is price per kilo misleading?

Film covers by area, not weight. A cheaper per-kilo price on thinner film usually produces a more expensive covering per square metre per season.

Q: Is expensive PO film really cheaper than PE over time?

For tunnels producing more than two seasons, usually yes - the higher unit price is divided across 3-5 years of production while seasonal PE pays film plus labor every year.

Q: What tolerance should I demand in writing?

Ask for the tolerance in the contract and the remedy if an audited roll falls outside it. An unwritten tolerance invites thinner film.

Q: What information should I send for a comparable quote?

Span arc and length, anchoring method, crop, climate and target lifespan. MOQ is 1,000 kg per specification, lead time typically 30+ days, free samples for trials.

2026-09-25

Greenhouse Film · Buying Guide

Greenhouse Film Cost per Square Metre (and per Season): How to Compare Quotes the Right Way

The cheapest roll on the quotation sheet is rarely the cheapest covering. Two quotes for “the same” film can differ by 30% in real cost once thickness, width, tolerance and service life enter the math. This guide shows how to convert any quote into cost per square metre — and then into cost per season, which is the number that actually decides.

💰 Cost per m² 📆 Cost per season 📏 Tolerance matters 📋 6-item quote checklist

At a glance

Price per kilo misleads: film is bought by area, so convert every quote to cost per square metre before comparing.
Three numbers hide in every quote: nominal thickness, actual tolerance, and rated service life.
Cost per season = (film + installation labor) ÷ seasons of production. A longer-lived film at a higher unit price usually wins this division.
Wrong width is a hidden cost: non-custom widths mean offcut waste and extra seaming labor.
A quote without tolerance in writing is an invitation to receive thinner film than you ordered.

The Three Numbers a Quote Tries Not to Mention

Every greenhouse film quote contains a price. The honest ones also contain three numbers that determine what that price is worth:

📏

Nominal thickness

Within the 100–200 mic working range, thickness drives material cost and strength. Compare quotes at equal nominal thickness only.

🎯

Actual tolerance

Film sold at “150 mic” can run 138 at the thin spots. Ask for the tolerance clause in writing.

📆

Rated service life

1–2 seasons (basic PE) or 3–5 years (UV-stabilized PO). This number divides everything else.

How to Calculate Cost per Square Metre

Film is produced and sold by weight, but it covers by area. The bridge is the film’s area density:

The conversion

Area density (kg/m²) = thickness (mic) × density factor. For LDPE-based film, one micron of thickness corresponds to roughly 0.92 g/m² — so 150 mic weighs about 0.138 kg/m².
Cost per m² = price per kg × kg per m². A quote at 12 USD/kg for 150 mic film is about 1.66 USD/m².
Why “per kilo” misleads: a cheaper per-kilo price on thinner film is often a more expensive covering. Always finish the division to per square metre.

Worked example: Quote A: 11.0 USD/kg at a nominal 140 mic. Quote B: 12.0 USD/kg at a nominal 150 mic with ±5% tolerance. Per square metre, A ≈ 1.42 USD, B ≈ 1.66 USD — but if A’s tolerance runs 8% light, its real average thickness is under 129 mic, and its lifespan drops disproportionately. The 0.24 USD/m² gap buys more than it appears to.

How to Calculate Cost per Season — the Number That Decides

A greenhouse produces in seasons; the film should be accounted the same way. The formula:

Cost per season

Cost per season = (film cost + installation labor + downtime cost) ÷ seasons of production delivered.
PE film replaced every season: every season pays the full film price plus a full re-covering labor day plus lost production days during the swap.
PO film rated 3–5 years: the same costs are divided by four or more — and the covering is not touched during the peaks of your growing calendar.

Cost item (illustrative, per 1,000 m² house)	PE, replaced every season	PO, replaced every 4 years
Film purchases per 4-year cycle	4 × cheaper film	1 × PO film
Installation labor per 4-year cycle	4 × full re-covering	1 × installation
Production downtime	Days lost every season	Once in 4 years
Light quality late in each film’s life	Degrades within the season	Held near 90% through the lifespan
Effective cost per season	High — everything paid annually	Low — everything divided by 4+

The pattern repeats across our export markets: once a tunnel produces more than two seasons, PO film’s cost per season typically matches or beats PE — with better light the whole way through. Run the formula on your own labor rate and the result is usually not close.

The Hidden Cost of the Wrong Width

Stock widths force a choice between two wastes: order wider than the span and pay for offcut polymer you bury in a corner, or order narrower and seam two rolls in the field — which costs labor today and adds a stress point for the life of the cover. Custom width, produced to your span’s arc plus anchoring allowance, eliminates both. It is also usually cheaper than buyers expect, because the factory saves as much on tailored production as you save on waste.

What Thickness Tolerance Means for Your Wallet

Tolerance is a price issue disguised as a quality issue. Film billed at 150 mic but actually averaging 140 mic delivers roughly 7% less polymer — and strength and lifespan fall faster than the polymer percentage, because thin spots fail first. When you compare quotes, ask each supplier two questions: What is your tolerance in writing? and What do I receive if an audited roll falls outside it? Our tolerance is stated on the specification sheet for every order in the 100–200 mic range; the thickness you audit is the thickness you paid for.

Purchasing Checklist: What Every Quote Must Include

Before you compare two quotes, check both contain

Nominal thickness in mic, within a stated range (100–200 mic).
Written tolerance and the remedy if an audited roll falls outside it.
Width and length per roll — and whether the width matches your span’s arc.
Rated service life for your region’s UV, with the test basis.
Functional layers: anti-drip, anti-fog, thermal — specified, not implied.
Terms: MOQ (ours is 1,000 kg per specification), lead time (30+ days), and free sample policy.

Send us your span dimensions and climate and we will return both a PE and a PO option priced per square metre and per season — so the comparison happens on your own numbers. Free samples available for trial bays.

Frequently Asked Questions

How do I convert a per-kilo film price to cost per square metre?

Multiply the per-kilo price by the film’s area weight: thickness in mic × ~0.92 g/m² per mic. A 12 USD/kg quote for 150 mic film is roughly 1.66 USD/m². Then divide by rated seasons of life for the real number.

Why is price per kilo misleading?

Because film covers by area, not weight. A cheaper per-kilo price on thinner film usually produces a more expensive covering per square metre per season.

Is expensive PO film really cheaper than PE over time?

For tunnels producing more than two seasons, usually yes: the PO film’s higher unit price is divided across 3–5 years of production, while seasonal PE pays film plus labor every year. Downtime during re-covering pushes the balance further toward PO.

What tolerance should I demand in writing?

Ask for the tolerance to be stated in the contract (we state ours on the specification sheet) and ask what happens if an audited roll falls outside it. An unwritten tolerance is an invitation to receive thinner film.

Does custom width cost more?

Usually less in total: custom width eliminates offcut waste and field seaming. You pay only for the area that actually covers your greenhouse.

What information should I send for a comparable quote?

Span arc and length, anchoring method, crop, climate region and target lifespan. We return PE and PO options priced per square metre and per season. MOQ is 1,000 kg per specification; lead time typically 30+ days; free samples for trials.

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