From Your Driveway to the Scale: A Plain-English Guide to Scrap Metal Weighing and Grading

Most people picture scrap collection as a quick driveway transaction: point at a pile, agree a number, watch it go. The reality is more like a small supply chain. Between your old boiler and the melting furnace, there’s a collection vehicle, a weighbridge, a sorting bench and a paper trail. Knowing how those steps fit together is the difference between accepting a vague figure and recognising a fair one.

At B&P Scrap Co., we work in plain English, so here’s the plain-English version of what happens after you book a collection in 2026.

The collection starts before the van arrives

A decent collector will ask a few questions before anyone sets off. What have you got? Is it mostly bulky steel, mixed household metal, or something like copper pipe and cylinders? Is it accessible, or is it at the back of a shed behind three bikes and a water butt? These details affect the vehicle, the crew and sometimes the price.

This isn’t admin for the sake of it. A washing machine, a bike frame and a length of lead flashing don’t belong in the same grade, and they don’t behave the same way on the scale. Giving clear information up front means fewer surprises when the load is weighed.

What happens on the weighbridge

A weighbridge is simply a large, calibrated set of scales set into the ground. The collection vehicle drives on, and the system records its weight. If the vehicle arrives empty, that gives the tare weight. Load it up, weigh it again, and you get the gross weight. Subtract tare from gross and you have the net weight of your scrap.

That sounds basic, and it is — but the details matter. A public weighbridge should be tested and calibrated, and the operator should be able to produce a ticket showing the date, the vehicle, the gross weight, the tare weight and the net weight. If your collection is weighed at a yard, ask for the ticket. If it’s weighed on mobile scales, ask when those scales were last checked.

A fair collector won’t mind you asking. A vague answer is more useful as a warning sign than as reassurance.

Gross, tare and net — the three numbers that matter

When people say they were ‘done’ on a scrap price, the problem is often not the headline rate per kilo. It’s the weight. Did the vehicle weigh in with a full fuel tank and a passenger? Was the tare weight taken from the same vehicle? Was the net weight written down clearly?

You don’t need to be a weighbridge clerk to protect yourself. Ask for the net weight in kilograms, the grade applied and the price per kilo. Multiply them and check the total. If the maths doesn’t match the receipt, ask why. Simple arithmetic catches most problems before they become arguments.

How metal grades change the price

Scrap isn’t one material. It’s a family of materials with different values and different processing routes.

• Heavy iron: thick steel plate, machinery parts, heavy cast iron and similar dense items.
• Light iron: thinner steel sheet, old appliances, bike frames and mixed steel items.
• Copper: pipe, cable, cylinders and fittings, usually sorted by cleanliness and type.
• Brass: taps, fittings and valves.
• Aluminium: extrusions, sheets, cast items and some guttering.
• Lead: flashing and old pipe work.
• Stainless steel: sinks, cutlery, kitchen equipment and some fixings.

A single item can contain several grades. A washing machine is mostly steel, but it also has a motor, wiring, plastic and sometimes a concrete weight. A bike is often aluminium, but the tyres, grips and cables are not. A fair price reflects what is actually metal and what has to be separated.

Deductions: fair, explained, or just vague?

Deductions are not automatically a red flag. If a load contains plastic, rubber, concrete, wood or general waste, those materials have to be removed before the metal can be processed. The cost of doing that is real.

The problem is the unexplained deduction. ‘That’s just the price’ is not an explanation. A fair collector should be able to tell you what is being deducted and why. Was there excess plastic on the appliance? Was the load wet? Were there non-metal items mixed in? Was a sealed cylinder or fuel tank present?

Some items need special handling rather than a simple deduction. Gas cylinders, fuel tanks, oil-filled equipment and anything containing hazardous chemicals should be dealt with properly, not crushed into a mixed load. If a collector brushes that aside, ask more questions.

Paperwork you should expect in 2026

Scrap metal collection is regulated, and the paperwork is there for a reason. A legitimate collector should be able to show a waste carrier registration and, where relevant, a scrap metal dealer licence. For household collections, you should still receive a clear receipt showing the weight, grade, price per kilo and total paid.

If the load is commercial, ask about a waste transfer note. If the collector can’t explain what paperwork applies, that’s a sign to slow down. Good operators are used to these questions because they deal with them every day.

Questions worth asking before you book

Before you hand over a pile of metal, try these:

1. Are you a licensed waste carrier and scrap metal dealer?
2. Will my load be weighed on a calibrated weighbridge, and can I see the ticket?
3. How will you grade the metal, and what price per kilo applies to each grade?
4. What deductions might apply, and how will you explain them?
5. What happens to non-metal parts and any hazardous items?
6. Will I get a receipt showing net weight, grade and total price?

None of these questions are unreasonable. They are the basics of a fair transaction. At B&P Scrap Co., we’d rather explain the weighbridge, the grade and the deduction than leave you wondering what happened to your old boiler. Clear pricing starts with clear weighing — and that starts before the van leaves the yard.