Industry Trends

Rubbish Bags Buying Checklist: 8 Steps I Run Before Approving Any Order

Who this checklist is for

If you sign off on bin liners and rubbish bags in bulk — office floors, warehouses, job sites — this is the order I run, in this sequence. I buy for a 130-person commercial contractor. Consumables run about $240,000 a year and roughly $31,000 of that is bags: dustbin plastic bags for the office floors, heavy liners for site cleanup, and everything in between.

Eight steps. Three of them are the ones people skip, and those three are usually where the money leaks.

One caveat before the list: the numbers below come out of my own tracking sheet, not an industry average. Your freight lanes and volumes will move things around.

The 8-step order

Step 1 — Measure the container, not the bag you happen to have on hand

This is the first step most people skip. They grab whatever liner is under the sink, eyeball it, and order more of the same size. Then they wonder why half the bins look like they're wearing a shirt two sizes too small.

Supplier specs list flat width, not opening width. A bag with a 30-inch flat width opens to roughly 60 inches around. That circumference is the number that actually matters.

Two formulas cover almost everything:

• Round bins: flat width should be at least diameter × 1.7. A 20-inch round bin needs about 34 inches flat width — that extra 0.7 is for the overhang.
• Rectangular bins: flat width should be at least (length + width) + 3 inches. An 18 × 24 inch bin has a circumference of 84 inches, so half of that is 42, and you want 44–46 so the bag actually stays put.

I skipped this once and ordered 33-inch flat width liners for a 20-inch round bin. Not a catastrophe, just 500 bags that wouldn't stay under the rim, and a lot of double-bagging. About $140 down the drain because I didn't spend ninety seconds with a tape measure.

Step 2 — Convert the gauge properly, then ask for the minimum

Thickness gets quoted in mils in the US and microns almost everywhere else. 1 mil = 25.4 microns. If a spec sheet mixes the two, sort that out before you compare anything.

Rough bands, from my own orders:

• 0.5–0.7 mil — light duty, office bins, paper waste only
• 1.0–1.5 mil — standard commercial liners
• 2.0–4.0 mil — heavy duty, site work, sharp debris

Here's the part that costs people money: nominal thickness and minimum thickness aren't the same thing. Film is blown, and the gauge varies across the bubble. A supplier quoted me "1.5 mil" on a heavy liner. We spot-checked 40 bags with a micrometer and got an average of 1.21 mil, with low points at 1.09. That's a 27% shortfall from the quoted number, and nobody lied on the spec sheet — they just quoted the nominal figure.

Ask for the minimum. If they can't give you one, that tells you something about their process control.

Resin choice matters too. HDPE is thinner, stiffer, noisier, and has higher load capacity at the same gauge, but it tears and runs once it punctures. LDPE is softer, drapes better, and resists punctures. LLDPE sits between the two and is what I specify for anything that touches debris.

I should add: gauge should be checked at the seal, not just the body. The seal area is usually the thinnest part of the bag and the first place it fails.

Step 3 — Match the spec to the actual job, not the category name

"Rubbish bags" covers about five different products, and buying them as one lump is how you end up overpaying on half of them and under-specifying the other half.

Construction debris. This is the one that punishes shortcuts. Tile offcuts, drywall pieces, rebar ends — sharp material will open a 1.5-mil liner in seconds. For custom construction garbage bags I specify 3-mil minimum LLDPE, usually 42 or 55 gallon. The spec sheet should list puncture resistance, not just capacity. A bag that holds 55 gallons of air is not the same as one that holds 55 gallons of concrete chunks.

Extra large rubbish bags. Site cleanup, yard waste, end-of-project clearout. 95 gallon and up, and flat widths often run to 38 inches. Capacity in gallons tells you volume. It tells you nothing about whether the bag will fit the opening you need. Those are two different problems.

Diaper pail liners. Completely different product family. If you're buying replacement liners — the generic ones, not the brand-name refills — they're specified by circumference and ring compatibility, not by gallon count. Narrow tube, multi-layer film, twists or clips into a ring. Buy one that doesn't match your ring diameter and you've bought nothing.

Bin liners for small bins. 4 to 6 gallon, roughly 17–18 inches flat width. The most common mistake here is buying too thick. A small office bin holding paper cups does not need 1.5 mil. I've seen facilities teams pay a 40% premium on liners that were never going to be stressed in the first place.

Dustbin plastic bags. Standard indoor waste, 1.0–1.2 mil, sized to the bin. Boring, and that's the point.

Step 4 — Build a spec sheet before you look at a single price

Second commonly skipped step. Write the spec first, then send the identical sheet to every supplier.

My sheet has these fields: flat width, length, minimum gauge, nominal gauge, resin, color, roll length or count per case, core diameter, print required or not, and packaging format.

Without it, you're comparing two different products and calling it a price comparison. I once had two quotes that looked like a 20% gap. One was priced per case of 200, the other per case of 25 rolls × 20 bags. Same bag, and the "cheap" one was actually 4 cents per liner more expensive.

Step 5 — Calculate landed cost, not unit price

Unit price is one of five numbers. The other four: freight, pallet or handling fees, damage and claim rate, and payment terms.

A real comparison from a 2023 reorder. The low bidder quoted $0.33 per 55-gallon liner. Our incumbent quoted $0.41, freight included. On paper, that's a 20% saving — roughly $1,600 across our annual volume.

Then I added it up. The low bidder charged $180 per shipment on our order pattern, we'd seen a 4% damage rate on their previous trial, and their lead time was listed as "5 to 12 business days." Landed cost came to about $0.38 a liner, and a missed delivery window on a site cleanup costs far more than three cents. We stayed with the incumbent.

That's the whole idea behind value over price. The lowest quote isn't wrong, it's just incomplete. Add the missing numbers and it stops being the lowest quote.

Step 6 — Ask for test data, not adjectives

"Heavy duty," "industrial strength," and "premium" mean nothing. Test standards do.

The three I ask about:

• ASTM D882 — tensile strength of thin plastic sheeting
• ASTM D1709 — dart impact, which is the closest thing to a puncture test
• ASTM D1922 — tear propagation

If a supplier can't produce numbers, that's not automatically a red flag — some distributors genuinely don't have lab access — but it does mean they can't tell you whether their product will hold up to your application, only that it usually works for other people.

On the compostable side, ASTM D6400 is the US certification standard, and the FTC's Green Guides require that environmental claims like "compostable" or "biodegradable" be substantiated before you make them. If a supplier talks about eco-friendly liners and hands you nothing in writing, walk away. That's not caution, that's exposure.

Step 7 — Buy a case, not a pallet

Never commit to annual volume on a product you haven't destroyed.

My test: fill the bag to about 80% with the actual waste stream, tie it off, and drop it from the height it'll actually get dropped from. Not desk height — the height of a dumpster lip. Then pick it up by the top and see whether the seal survives.

I skipped this once because we were rushing and the spec looked identical to what we'd been buying. It wasn't. The new supplier had moved to a thinner seal. We went through 14 cases before anyone noticed the failure pattern. That's money that never shows up in a cost report, because it got filed under "general waste supplies."

Step 8 — Put three protections in the annual contract

If you're signing for a year, get these in writing:

1. Price protection — how long the quoted price holds, and how much notice they owe you before an increase. Resin prices move with feedstock and energy, so 90 days is reasonable and 30 is not.
2. Specification change notice. If they switch resin, gauge, or film supplier, you want to know before the shipment arrives, not after the bins start leaking.
3. A defined lead time. "3 to 5 days" — is that ship or arrive? Written as ship, it means very little. Written as arrive, it's a commitment you can hold them to.

What usually goes wrong

Six things I've watched repeat across vendors and facilities teams:

• Buying by gallon count instead of opening size. Gallons measure volume. Flat width determines fit.
• Trusting the nominal gauge. Ask for minimum thickness. If they don't have it, assume the low points are worse than advertised.
• Comparing unit price across mismatched case configurations. Normalize to cost per liner before anything else.
• Assuming custom printing has no setup cost. Plate or die charges can run into the hundreds, and small runs rarely justify them. Ask for the setup fee in writing alongside the per-unit price.
• Forgetting storage. Bags are bulky. A year's supply of 95-gallon liners takes real square footage, and if you're renting that space, it's a cost.
• Skipping the buffer. Lead times slip. Build in the cushion rather than relying on a supplier's estimate holding true during their busy season.

Two honest limits on all of this. First, pricing referenced here reflects what I was seeing in early 2025 — resin costs track energy and feedstock markets, so verify current rates before you build a budget on these numbers. Second, I'm not a polymer engineer. I can't tell you how a specific resin blend behaves under extended UV exposure or at freezer temperatures. If your application involves either, talk to someone who formulates film for a living. What I can tell you is how to compare what two vendors are actually putting in front of you, which is usually where the savings live anyway.