Tracking stock by size on site: rebar, tiles and pipes

Most stock problems on a building job aren't about running out of something. They're about running out of the right version of something.

You have plenty of rebar, but it's #5 and the slab needs #4. You have 18 boxes of tile, but they're the wrong color for the bathroom. The spreadsheet says "PVC pipe: 40", and nobody knows whether that's 1-inch or 2-inch.

Counting stock by name hides exactly the detail that stops work. Here's how to count it in a way that holds up.

Count each size, under one item

Keep one item per material, and give it sizes:

• Rebar: #3, #4, #5
• Floor tile: grey matte, white gloss
• PVC pipe: ½ in, 1 in, 2 in

Then every movement, in or out, says which size it was. You still see "Rebar: 88 left" as a total, and underneath it "#4: 50 · #5: 38". That's the line that stops someone ordering more #5 when the job needs #4.

Keeping sizes under one item, rather than three separate items, has a second benefit. Reports and costs stay together: you can see what rebar cost on the job as a whole, and still see each size on its own.

Count in the unit you use, buy in the unit you're sold

Cement comes in bags, rebar in bundles, tiles in boxes of a set number of square feet. But on site you use them one bag, one bar or one square foot at a time.

The way to keep both straight is to choose the unit you count in, then say how many come in a pack:

• Rebar: counted in pieces, bought in bundles of 20
• Tile: counted in sq ft, bought in boxes of 12 sq ft
• Cement: counted in bags

When a delivery of 6 bundles arrives, it goes in as 120 pieces. When the crew uses 14 bars, that's 14 pieces out. Nobody does division at 7 in the morning.

Three numbers for every item

For each item and size, keep:

• In: everything received, from purchases and from other sites.
• Used: everything taken for the job.
• Left: In minus Used.

Here's the rebar on one site after three weeks:

If the count on the ground doesn't match "Left", you know something was used without being written down, or something walked off. Either way you find out now, not at the end of the job.

Set a warning level, not a reorder date

Every material has a point where you should order more, based on how fast you use it and how long the yard takes to deliver. For drywall it might be 30 sheets; for cement maybe 15 bags.

Write that number down once. When stock drops below it, the item is flagged as low. It's a simple thing, and it's the difference between ordering on Tuesday and stopping work on Thursday.

When stock moves between sites

Contractors often run two or three jobs at once and move materials between them. If the stock list doesn't know about the move, one site looks short and the other has stock it can't explain.

Record a move as one entry: out of one site, into the other, with the size. Both lists stay right, and the cost follows the material, so the job that used the rebar is the job that pays for it.

How Finlivo Business does it

Finlivo Business builds this into its stock items:

• Each item has a unit, an optional pack (a bundle of 20, a box of 12 sq ft) and as many sizes or types as you need.
• In, Used and Left are shown for every size, with a total underneath.
• A warning level flags anything running low, on the stock list and in a morning reminder.
• Purchases can go straight into stock as you record them, so a delivery doesn't need typing twice.
• Stock can be shared across a group of ledgers, or moved between sites, with each move kept in the item's history.

Whatever you use to track it, the principle is the same. Count what people on site actually ask for, in the units they actually use, and the stock list stops being a guess.