Selling by the linear metre: coils, lengths, minimum cuts and stock in metres

“I need 37 metres of hose.” If you sell in 25 m coils, your customer needs two. If you sell cut to length in 1 m steps, they need 37. If you sell 3 m profiles, they need 13, and will have 2 m left over. Each material has its own way of being supplied, and if the store does not do the calculation, the customer does, or phones you so that you do it.

Selling by length done right has one rule: the customer asks for the measurement they need and the store translates that measurement into units your warehouse can prepare.

The four formats for selling by length

• Whole coils or drums. Cable, rope, chain, hose, LED strip. Ordered in metres and supplied as whole coils of a fixed length.
• Whole lengths. Tubes, profiles, mouldings, skirting boards, bars. Each length measures what it measures; it is not cut.
• Packs of lengths. A pack with a number of lengths of a given size. The pack's length is the number of lengths times their size.
• Cut to length. Fabric, cable by the metre, tape, rope from a large roll. Sold in cutting steps (for example, of 0.5 m or 1 m).

How the quantity is calculated

1. Length requested by the customer, in the catalogue's unit.
2. Plus whatever wastage makes sense: for profiles, for cuts and mitres; for cable, for connections and runs that are never exact.
3. Divided by the length of one sales unit (coil, length, pack or cutting step).
4. Rounded up, unless there is a reason for another criterion.

Minimum and maximum cuts

The minimum cut exists because cutting has a cost: time, roll wastage and an end piece that is hard to sell. If you have a minimum, it must be in three places:

• On the product page, in writing.
• In the calculator, which must not allow ordering less.
• In the cart, which must not allow the quantity to drop below it when edited.

A maximum also makes sense: if a cut exceeds what fits on one roll, it is better for the product page to say so than for the warehouse to discover that two pieces have to be supplied when the customer expected a continuous one.

Units: metres, centimetres, feet

Most stores in Spain work in metres, but not all products do: imported LED strip comes in feet, tape in centimetres, industrial piping in millimetres. It is useful to be able to set a unit for the store and change it product by product, and for the customer always to see the same unit on the product page, in the cart and on the invoice.

Stock in metres

With whole coils and lengths, stock is counted in units, as always. With cut to length it is not: you have 200 m of fabric on a roll and sell pieces. Stock has to be held in metres and deducted in metres, and the store must prevent selling 15 m if 12 are left.

• Decide per product whether stock is in units or in length.
• If a roll is left with a remnant below the minimum cut, plan for it: either sell it as an offcut or write it off.
• Do physical counts of cut-to-length rolls more often than the rest: that is where discrepancies arise most.

Price per metre: how to show it

The product price in PrestaShop should be that of one sales unit (a coil, a length, a cutting step). The price per metre goes on the product page as information. If you sell to consumers, Spain's price indication rules (Royal Decree 3423/2000) require the price per unit of measure in many cases: showing it settles the question.

What does not work is the opposite: setting a price per metre and a quantity in metres for a product supplied in 25 m coils. The customer orders 37 “units”, the warehouse does not know what to prepare and the invoice does not match the delivery note.

Common mistakes

1. Selling cable “by the metre” when you actually only supply whole coils.
2. Not mentioning the minimum cut until the customer has already paid.
3. Calculating lengths without wastage for profiles that are mitre-cut.
4. The order not stating what length the customer asked for: impossible to handle a complaint.
5. Cut-to-length stock kept in units: one day you sell a roll that no longer exists.

Checklist

• Format chosen per product: coil, length, pack or cut.
• Length per unit checked with the supplier.
• Default wastage and the product's own, if different.
• Minimum and maximum units.
• A consistent unit of measure on the product page, cart and invoice.
• Stock in the correct unit.
• A test order checked all the way to the confirmation email.

Frequently asked questions

Can I sell the same cable as a coil and cut to length? Yes, but as two different products (or two combinations), each with its own format, price and stock. Mixing them in a single product makes it impossible to know what you have in the warehouse. Usually the whole coil works out slightly cheaper per metre than the cut, and showing that price per metre on both product pages helps the customer decide.

What do I do with offcuts? If the end of a roll is below the minimum cut, you can publish it as its own product (“1.3 m offcut”) with stock 1, or write it off as wastage. What you should not do is leave it in the roll's stock: the store will think it can sell a cut that does not exist.

How do I calculate shipping for an order by the metre? The carrier charges by weight and volume, not by metres. Each sales unit (coil, length, cutting step) must have its weight and, for long lengths, its dimensions, because a 6 m profile does not travel on just any service. Check your longest products with your carrier before publishing them.

What if the customer needs an exact cut, without steps? Set the smallest cutting step you can supply (for example, 10 cm). That way the customer orders almost exactly what they need and your warehouse still works with measurements it can cut and check.

How to handle it in PrestaShop

RKR Linear Pricing Pro adds a calculator to the product page where the customer types in the length and immediately sees how many coils, lengths, packs or cutting steps they need, the total length they will receive, the unit price and the total. It works with six units of measure (mm, cm, m, km, feet and inches) at store or product level, adds a default wastage and a per-product one, rounds up by default, supports minimum and maximum units and keeps stock in metres. Your product price is still that of one sales unit, and the details reach the cart, order, PDF invoice and emails.

For what you sell by area (flooring, tiles, boards), RKR Area Pricing Pro applies the same logic to m².