The complete guide to bin liners and refuse sacks

A refuse sack is four decisions: how big, how thick, what polymer, and how it is made. Get any of them wrong and the sack fails in a way that looks like a quality problem and is actually a specification problem.

This guide is the long version of the four calculators on this site. If you want the answer rather than the reasoning, the bin liner size finder and the sack duty selector will give it to you in about fifteen seconds.

1. Size

How EN 13592 writes it

Two numbers, both in millimetres, both measured on the sack laid flat: usable width P and usable length L. A sack marked 700/1100 is 700 mm wide and 1100 mm long as it lies. The order never changes.

Neither number includes the seam or the fold at the top. If a quotation gives you three numbers, the middle one is a gusset and the sack is not a plain tube.

Working the size out from the bin

The naive move is to match the sack’s circumference to the bin’s perimeter. It over-specifies by about a quarter, because a sack does not sit into the corners of a bin — it rounds them.

Treating the opening as an ellipse gives the figure that matches what is actually sold:

For a 240 litre wheeled bin with a 560 × 700 mm opening that is 990 mm, and the trade stocks 950 to 1000. For a round bin, where the width and the depth are both the diameter, it reduces to half the circumference.

Bin	Sack	Sack holds
30 l pedal bin	500/650	about 30 l
50 l swing bin	600/800	about 55 l
80 l wheeled bin	750/1000	about 110 l
120 l wheeled bin	800/1050	about 130 l
240 l wheeled bin	1000/1200	about 220 l
360 l wheeled bin	1150/1250	about 280 l

Above 360 litres a liner is made gusseted rather than as a plain tube: a 1900 mm lay-flat tube is not a product anybody can open. The width still follows the same rule; the length is specified against the container.

Why the sack holds less than the bin

A bin is rated to the brim. A sack is gathered and tied. A 240 litre bin taking a liner that holds about 220 is normal and correct — if your bins genuinely get filled to the rim, take the next length up rather than the next width.

2. Thickness

Microns, gauge and the rounding

Gauge is one hundredth of a thousandth of an inch, so one gauge is 0.254 microns. The sack trade rounds that to four gauge per micron, which is where the tidy numbers come from — 120 gauge for 30 µm, 200 for 50, 500 for 125.

The rounding runs 1.6% light and nobody argues about it. What matters is that it is a rounding of one scale, not a second scale: stretch film uses the same conversion. See the micron and gauge converter.

What the waste demands

What goes in	Material	Thickness	Gauge	Duty
Office and dry light waste	HDPE	12 µm	—	Light
General commercial waste	LDPE	30 µm	120	Medium
Food and wet waste	LDPE	40 µm	160	Medium
Garden and green waste	LDPE	50 µm	200	Heavy
Construction waste	LDPE	75 µm	300	Extra heavy
Rubble, aggregate, plaster	LDPE	125 µm	500	Rubble grade

Move up one row if the sack is lifted out by hand, carried downstairs or dropped down a chute. A tipped bin carries its own load. A sack that is lifted carries the load on its own film and its base seam, and that is where the failures happen.

What the load demands

Capacity rises with thickness and with width — a wider sack spreads the same load over more material:

A 500 mm LDPE sack at 30 µm carries about 7.5 kg. A 450 mm HDPE sack at 12 µm carries about 5.7 kg, which is the figure the trade quotes for light office waste.

Take the higher of the two answers — the waste floor and the load arithmetic. They fail differently: one is a tear, the other is a puncture, and tensile capacity does nothing about a corner going through the wall.

3. Polymer

This gets treated as a price question and it is not.

HDPE carries roughly twice the tensile load of LDPE per micron and much less against puncture. It is thin, it rustles, and for paper and dry packaging it is genuinely the right material rather than the cheap one — a 12 µm HDPE sack does the work of a 25 µm LDPE one using half the polyethylene.

LDPE stretches before it tears and takes a puncture that would open HDPE instantly. Anything with a corner, a bone, a broken bottle or a wet load needs it.

So a supplier quoting “20 µm” against your “40 µm LDPE” may be offering a like-for-like replacement in HDPE, or may be offering half the sack. The micron figure alone does not tell you which. Always ask for the polymer.

Recycled content

Post-consumer recycled polyethylene is normal in refuse sacks and, for most grades, invisible in use. Two things are worth knowing:

• Colour. Recycled content darkens the sack. A 100% recycled black sack is indistinguishable; a recycled white one is not white.
• Consistency. Higher recycled percentages mean more variation between batches. For a general waste sack that is irrelevant. For a sack that has to pass a drop test every time, specify the maximum recycled percentage you will accept rather than leaving it open.

Under PPWR, recycled content in packaging is heading towards mandatory targets. Sacks made from post-consumer material also usually cost less than virgin, which is the rare case where the compliant answer and the cheap answer agree.

4. Construction

Where sacks actually fail

At the base seam, from overfilling. A 125 µm rubble sack holds 25 kg all day and splits at 40. The working rule is to fill a heavy-duty sack to about a third of its volume. No specification change fixes a sack that is being filled to the top.

At the neck, from being carried by the body. If there is not enough length above the waste to gather and grip, the sack gets carried by its middle and the load hangs on a small area of film. This is why the size finder adds 100 mm when you tell it the sacks are carried.

Down a fold, from being stored badly. Polyethylene creases take a set. A pallet of sacks stored under something heavy for six months will fail along the fold lines, and it will look like a material fault.

Star seal, gusset or flat

• Star sealed — the base is sealed in a cross. No corners to leak, spreads the load evenly. The default for anything wet or heavy.
• Gusseted — sides folded in, so the sack opens square. Right for large containers and for lining boxes.
• Flat bottom — a single straight seal. Cheapest, and the one with corners that leak. Fine for dry waste.

If a quotation does not say which, assume flat.

5. What a quotation should state

Ours state all of this, and it is worth holding any supplier to the same list:

Line	Why it matters
EN 13592 size, P/L in mm	The only unambiguous way to state a size
Thickness in microns	Gauge alone invites the rounding argument
Polymer, and recycled percentage	HDPE at 20 µm is not LDPE at 20 µm
Colour	Especially for clinical streams
Seal type	Star, gusset or flat
Number per roll or per case	Sacks are used per piece and priced per tonne
Cases per pallet	It decides the freight

Sacks are made to a size, not to a nominal litre rating. A “240 litre sack” from two suppliers can differ by 100 mm in either direction, and the litre figure is marketing.

Clinical and offensive waste

Colour and labelling come before thickness. The stream is set by whoever collects the waste — orange, yellow, yellow-and-black, tiger stripe — and a correctly made sack in the wrong colour is a rejected collection.

Confirm the colour with the collector before ordering, not with the supplier.

What to send us

The fastest route to a quotation that is right first time is a photograph of the case label of what you buy today. The product code and pack quantity are usually enough for us to match it, and if your current specification is heavier than the job needs we will say so and quote the lighter one alongside it.

A thinner sack that works is a better order than a thicker one that comes back.