Plumbing contractors run on copper tubing, brass fittings, PVC, and fixtures — all commodity-backed materials with prices that move with the metals market. Fixture and material costs have risen more than 30% since 2020. The Overcharge Ledger tracks what your invoices actually reflect versus what you agreed to pay.
IBISWorld estimates $191.4 billion in U.S. plumbing industry revenue in 2026, growing at a 3.1% CAGR over five years. Approximately 132,000 plumbing businesses operate nationwide with an average net profit margin of 4.3%. That leaves almost no room for materials costs to drift without notice.
Fixture and material costs have risen more than 30% since 2020, tightening margins on every job where supplier pricing hasn't been formally renegotiated. Most hasn't. That gap is where the Overcharge Ledger lives.
New construction, remodel, and service repair in single and multi-family homes. High invoice volume, multiple material deliveries per job, and supplier relationships that run continuously across multiple projects.
Office buildings, hospitals, factories, schools, warehouses. Larger project scale means larger material orders — and more opportunities for SKU substitution and unquoted spend to go undetected across delivery schedules.
Process piping, hydronic heating, steam and high-pressure systems. Materials are highly specified — pipe schedule, alloy, fitting type. A specification deviation on the invoice is a compliance issue as much as a cost issue.
Emergency callouts and maintenance contracts. Fast-moving work means materials are ordered under pressure and invoiced after the fact. The average emergency plumbing call generates $450 in revenue — every materials overcharge on that call eats directly into the job margin.
The materials your plumbing supplier invoices you for are priced against base commodities — copper for tubing and fittings, brass for valves and connectors, PVC resin for drain waste and vent pipe. When those commodity prices move, your supplier's billing system adjusts. The question is whether your invoices reflect that movement accurately — or opportunistically.
The BLS Producer Price Index for Plumbing Fixtures and Fittings (WPU105) moved from 359.5 in October 2025 to 374.0 in February 2026 — a 4% increase in four months. Meanwhile, IBISWorld notes that fixture and fitting costs rose 28.4% between January 2021 and November 2025, with an additional 7.1% jump from December 2024 to November 2025.
Your supplier passes those increases through your invoice. The Overcharge Ledger maps your invoice prices against commodity index movement so you can see whether what you're being charged tracks the underlying market — or whether margin is being expanded on top of it. We record the data. We measure it. We verify it. We do not provide financial advice.
The Ledger is building commodity index tracking into every client dashboard. When copper or PVC resin moves, you see it — and you see whether your supplier's invoices moved with it, ahead of it, or beyond it. The data belongs to you. The decision is yours.
Your supplier adds a copper surcharge line item. Copper pulls back six months later. The surcharge line remains. It has become a permanent margin expansion disguised as a temporary commodity hedge.
You spec'd Type L copper. The delivery comes with Type M. Same diameter, thinner wall, lower cost to your supplier — but the invoice reflects Type L pricing. The difference is their margin expansion, not a commodity pass-through.
Brass quarter-turn valve quoted at one grade, invoiced at a higher-priced grade. Same description, different internal component rating. The Ledger catches this at 94–99% SKU match accuracy across your full invoice history.
These are not edge cases. Every pattern below has appeared in active plumbing contractor engagements. The examples are real finding types documented from supplier invoices.
Type L vs. Type M copper. Schedule 40 vs. Schedule 80 PVC. Same nominal diameter, different wall thickness, different cost basis — and a different price that wasn't agreed to. Description matches 99%. SKU does not.
Brass fittings come in multiple alloy grades and pressure ratings. A substitution on alloy or rating is invisible to a manual invoice review — the description says "brass elbow." The Ledger checks the SKU, not just the description.
Fixtures are quoted at project start. By delivery three, the per-unit price has moved. No change order. No notification. Just a line item that reads slightly different from the quote — multiplied across every fixture on the job.
A fuel or copper surcharge is added when the commodity moves. When the commodity pulls back, the surcharge does not. It becomes a permanent line item — and compounds across every invoice that follows.
Specialty valves, backflow preventers, access panels, and trim items frequently arrive without an agreed price. Your supplier sets the number at invoice time. In plumbing work, these items can represent a significant share of total job spend.
The same material delivery charged twice across two invoices — common when jobs span multiple phases and billing cycles. Volume across multiple active jobs makes this pattern invisible to manual review. The Ledger holds your full history simultaneously.
Every overcharge sourced and documented. Quote. Invoice. Line item. Dollar amount. Hand it to your plumbing supplier or your attorney — every number comes from their own documents.
Every item billed that had no agreed price — exported as an Excel-compatible spreadsheet. Send it directly to your supplier. They now have to respond with formal pricing on everything they have been billing unilaterally.
Every SKU substitution identified — pipe schedule, material type, alloy grade. Documented with the invoiced price, the quoted price, and the difference per unit across your full history.
Your invoice price history mapped against BLS PPI movement for copper, brass, and PVC. See exactly where your supplier's price increases track the commodity — and where they don't.
If the engagement requires it, the Ledger produces full methodology documentation — how every match was made, how every discrepancy was flagged — structured for your attorney to use in proceedings.
The Ledger produces a complete proof package. Your plumbing supplier cannot argue with their own document numbers. That is the architecture of the finding — not an allegation, a documented discrepancy between what was agreed and what was charged.
The gap between what you quoted and what you paid is the finding. What you do with it belongs entirely to you.
Monthly service. Flat rate. Cancel anytime. No contract required to start.