Section 1
The artifact, part one: tier every line by volatility
Before a swing ever happens, sort every material line in the estimate into one of three tiers. The tier decides how closely you watch the line and how you handle it when it moves. The discipline that makes this work is putting an as-of date on every Tier B and Tier C line. The as-of date is the day the price you used was actually valid, recorded next to the line, with the source it came from. A steel line does not just read "$18,000." It reads "$18,000, as of the supplier quote dated the 3rd, quote reference attached." That date is what lets you prove, later, that the price moved after you locked it and by how much. Without it, a mid-project adjustment is your word against the client's memory. With it, the adjustment is arithmetic on two dated numbers. The tiering also does something quieter and valuable: it tells you where to spend your attention. You do not need to watch the fastener line. You need to watch the three Tier C lines that can actually detonate the job. Tiering concentrates your monitoring on the small number of lines that carry almost all of the risk, so a one-person shop can actually keep up.
Section 2
The artifact, part two: the re-quote trigger table
Tiering isolates the volatile lines. The trigger table tells you what to do when one of them moves. Set this before the job starts, so the action is a policy you follow rather than a decision you improvise while a client waits. The bands are starting points, not law. A shop with thin margins might set the change-order trigger lower, and a shop on a long, steel-heavy job might set its stop-and-talk threshold tighter than 15 percent. The point is that the numbers exist before the swing, so when copper moves 15 percent in week three, you are executing a plan, not inventing a response under pressure.
Section 3
Reprice one line, never the whole estimate
This is the core move, and it is worth being explicit about why it matters so much. When you rebuild the entire estimate in response to one material moving, you invite the client to renegotiate everything. Every line you reopen is a line they can push back on, and you have converted a defensible one-line adjustment into a whole-quote fight you are likely to lose ground in. You also destroy your own credibility, because a contractor who reprices the whole job when one input moved looks like a contractor who is padding, not one who is passing through a real cost. Repricing the single line does the opposite. It says: everything else in this estimate is exactly as we agreed, and this one line, the steel, moved from its dated price to a new dated price, here is the source, here is the difference. The conversation is contained to the thing that actually changed. It is faster, it is more honest, and it is far easier to win, because you are asking the client to accept a documented fact about one line rather than a new number for the whole project. The tiering and the as-of dates are what make single-line repricing possible. If the estimate is one blob, you cannot surgically adjust one line, because there is no line to point at. If the estimate is tiered with dated volatile lines, the adjustment is already isolated before the swing happens. The structure you build at bid time is what buys you the clean move at swing time.
Section 4
A worked example: the 15% copper swing
A commercial electrical job. The estimate was built tiered. Copper wiring sits in Tier C at $6,000, stamped with an as-of date and the supplier quote it came from. Three weeks into the job, at procurement, copper has moved up 15 percent. The whole event touches one line of a multi-line estimate. The client is not asked to reopen the labor, the fittings, or the fixed lines. They are asked to accept $900 of documented copper movement, which is a much smaller and much more winnable conversation than a rebuilt quote. That containment is the entire payoff of building the estimate tiered in the first place.
Section 5
The two models underneath the method
The method rests on two simple ideas worth naming, because they explain why the discipline is shaped this way. The first is comparative statics, the habit of changing one variable and holding everything else constant. A tiered estimate is comparative statics built into your paperwork. When copper moves, you want to see the effect of that one change in isolation, with every other line frozen, so you can price the delta cleanly and defend it. An untiered estimate makes comparative statics impossible, because you cannot hold the rest constant if the rest is not separated out. The as-of date is the frozen baseline that the single moving variable is measured against. This is also why the method beats rebuilding the whole quote: rebuilding changes many variables at once, which is the opposite of what you want when only one thing actually moved. The second is real options, the value of a decision you get to make later with better information. The as-of date plus the trigger table is you holding an option to re-quote a line. You are not committing at bid time to eat whatever that line does. You are recording a baseline and a rule, which preserves your right to act when new price information arrives. The trigger bands are the strike prices on that option: below 3 percent you let it expire and absorb, above 15 percent you exercise it and reprice or escalate. Structuring the estimate this way is worth the most exactly when volatility is high, because that is when the option to adjust later is most valuable, and it costs almost nothing when volatility is low, because the option simply never gets exercised. The two models point at different things, which is why using both helps. Comparative statics keeps your adjustments clean and defensible line by line. Real options tells you the structure is worth building before you know whether any line will move. Where a job is both high-volatility and multi-line, the two together are the whole argument for tiering.
Section 6
What the method cannot do
Be honest about the boundary. This is a documentation and pricing discipline. It makes a real cost increase clean, defensible, and contained to one line. It does not decide whether the client has to pay it. That is a contract question, and it depends entirely on what your agreement says. A perfectly tiered estimate with immaculate as-of dates still recovers nothing if the contract is a naked fixed-price lump sum with no change-order or escalation mechanism, because there is no contractual door for the documented increase to walk through. The method makes you ready to collect. The contract decides whether you can. If any part of your handling relies on a change-order or escalation provision, that language is a matter for a construction attorney licensed in your jurisdiction, because a provision that reads fine alone can be unenforceable in the context of the whole contract. This is educational, and it is not legal advice. It also assumes you can actually get dated, sourced prices. In a genuinely chaotic supply environment, a supplier may not honor a quote long enough for the as-of date to mean much, and the gap between quote and mill invoice can swallow your baseline. When that happens, the answer is not better documentation. It is a shorter exposure window: quote closer to procurement, shorten your bid-expiration, and tier more lines into C so you are watching more of them. The method assumes prices hold long enough to be measured against. When they do not, you compress the window until they do.
Section 7
The fitness test
You are running job-costing that survives a swing if you can open any current estimate and point to which lines are Tier A, B, and C, read the as-of date and source on every volatile line, and name the exact percentage move that triggers a change order versus a stop-and-talk. When copper jumps 15 percent, you reprice the copper line, cite two dated prices, and leave the rest of the estimate untouched. You are still exposed, and you should rebuild your estimate template before the next volatile job, if your quotes are single undated blobs with no internal tiering. A blob gives you nowhere to isolate the line that moved, so every swing becomes a whole-quote renegotiation you enter without a dated baseline to stand on. Tier the estimate, date the volatile lines, and set the trigger bands before the job starts. The discipline is cheap to build and it is the difference between a $900 documented adjustment and a fight over the entire price.