Every habit in the previous chapter has a mirror image. The interviews surfaced a remarkably consistent set of anti-patterns — not exotic failures, but the everyday shortcuts that compound into seven-figure exposure over a project. We list them not to shame anyone (most of these have been done by every estimator who has ever worked under deadline pressure) but because naming them is the first step to designing them out of a team's process.
“As per plans and specs.”
The single most-cited anti-pattern across every firm size and geography we interviewed. A blanket “as per plans and specs” clause does no scoping work — it tells the sub to figure out the scope themselves and binds them to nothing the documents don't already say. A Senior Estimator at a Mid-Market Commercial GC: “There's people that take that route. It just opens you up for a lot of potential future disagreements, especially when you consider the amount of potentially discrepancies in a set of plans and specs or missing information or conflicting information.” A Canadian ICI Estimating Manager called the competitors who scope this way “just kind of a very lazy way of compiling scopes because at the end of the day you assume the market's going to pick up most of the scope and hopefully there's not too many anomalies.”
Copy-paste from the previous similar job
The second most-cited anti-pattern. The pattern is comforting: “we just built one of these last year, let's start with that scope sheet.” The pattern's consequence is the same comfort applied four projects later, when half the boilerplate doesn't match the drawings and nobody on the team knows which half.
If they continue to reuse scopes of work from a previous job… at some point it just doesn't apply to a specific job anymore. They've got scope gaps, or they've got double-up scopes between trades.
Letting PMs draft contract terms inside the scope sheet
A VP of Operations at a Top-ENR Canadian GC named this one with the most colorful phrasing in any of our interviews. The pattern is that PMs, under pressure, pull legal-sounding language from previous contracts into the body of the scope sheet — sometimes a flow-down clause they admire, sometimes a “get out of jail free” clause they remember saving a previous project. The result is contracts where, in his words, PMs “pick up stuff from previous contracts, drop it in, and it starts to include a lot of weasel clause language” — sometimes contradicting clauses already in the prime contract. The fix is structural: consolidate every prime-contract flow-down into a single dated appendix and lock the scope sheet to project-specific scope only.
Junior estimators stuffing previous scopes verbatim
A Construction Manager at a Top-ENR Canadian GC described what happens when scope writing is delegated without a checkpoint:
You typically have a junior guy that gets given scopes of work from three other projects. There's no idea what's applicable or not. He hasn't read the drawings yet, and what he'll do is just stuff everything in there and remove them as he goes — but he might miss a whole bunch and you might have some in there that aren't applicable.
Templates without a senior reviewer produce scope sheets that are simultaneously bloated and incomplete — the worst combination.
Generic inferred-scope laundry lists
“Elevator divider beam coordination” on a project with no elevator. “Dewatering during mass-timber installation” on a job with no water table issue. Catch-all clauses pulled forward from previous scopes train subs to ignore your inferred-scope section. A PM at a Canadian ICI GC: “One thing to just have like all these kind of catch-all statements, but if they don't even apply, it doesn't add much weight to the job.” On a mass-timber package one estimator described, a boilerplate “dewatering” line item pulled from a different trade made the sub conclude the entire scope was sloppy: “You guys are idiots. I'm mass timber. Why would I dewater my mass timber?”
The five-minutes-before-bid review
Bids arrive the day of close. The estimator has hours, sometimes minutes, to compare three to five sub bids across thirty-three CSI divisions for exclusions, clarifications, and substitutions. A Senior Estimator at a Mid-Market Canadian GC: “We send the drawings, we get the price. We have five minutes before the closing. You have 33 divisions to close. How quick can you review five if you have just two people reviewing the whole job?” Under those conditions, exclusions are not analyzed, they are tolerated. The cost shows up at buyout.
Trusting subs on a gentleman’s agreement
In a tighter market, subs who used to confirm scope verbally now exclude in writing. An Estimating Manager at a Canadian ICI GC: subs “have become more quick to clarify that ‘we've included this type because that type's not available’ or ‘hey, we're not including that one piece of scope because it's not in our wheelhouse.’” Treating a verbal “we got it” as binding is increasingly a trap. The scope sheet is the only document that survives a personnel turnover or a dispute.
“Just send the bid docs.”
The thinnest scope of all: emailing a sub the drawings and the spec book with the subject line “bid the electrical.” A Pre-Con Leader at a Small US Specialty GC named the pattern with unusual candor:
The truth is, we don't really write a comprehensive scope. Many times we just send the bid documents to them and say “bid the electrical.” We're shortcutting it. We're not being thorough in our subcontractor management. We're basically treating the subs the same way the owners are treating us.
The same speaker noted the predictable consequence: three subs receive the same package and return three wildly different numbers because they interpreted the gaps differently. The leveling work that should have happened in the scope sheet at issue now has to happen at bid open, on the clock.
Discovering scope gaps after handoff to operations
Several teams confessed that they only learn about scope gaps after the project is on site. A PM at a Mid-Market Self-Perform GC, asked how they track scope gaps: “I don't think we track them by any means. It's just, it happens. We deal with it and we move on.” Without measurement, the same gap appears on the next job, and the next.
The shortcut that has a name: “readily inferable”
Owners and CMs increasingly push design completeness risk onto the GC through “readily inferable” contract language. A Senior PM at a Canadian ICI GC: “Our construction management clients expect us to find the scope gaps in the design too now. They expect us to be designers and engineers.” Signing those contracts without a corresponding contingency or design-review allowance is itself an anti-pattern. The clause is enforceable; the price needs to reflect that.