Your Past Project Errors Are Your Best QC Checklist. Most Firms Can’t Use Them.
October 9, 2026 · Vit Vimal
Over the past year I’ve sat with about 100 QC leads at architecture, engineering, and construction firms. Almost every one of them told me some version of the same story.
A standard curtain wall detail doesn’t work on site. The contractor sends an RFI, the team scrambles, a change order gets signed, and the fix gets made in the field. The detail itself never gets updated. Two years later, a different team at the same firm pulls that same detail into a new project and gets the same RFI.
When I ask why it keeps happening, the answer is usually simple. The detail was in the firm’s standard library, so the team assumed it worked and reused it with a few small changes. Nothing told them it had already caused a problem.
Every past error is documented, but scattered across systems no one searches
Firms don’t lack data about their mistakes. Every RFI is a written record of a question the drawings couldn’t answer. Every change order is a receipt for what a miss cost. Every permit comment is a code issue someone else caught first. Every senior reviewer’s redline is a lesson in what to look for.
Put those together across five or ten past projects and you have something no generic checklist can give you: a list of the errors your firm makes, on your building types, with your consultants, ranked by what they cost you.
The problem is where it all lives. Once a project closes, the team moves on, and its records stay wherever the project happened to put them: network drives, Bluebeam sessions, Procore, email threads, Slack, and many other places.
A director at one large architecture firm walked us through his attempt to pull RFIs from 10 to 12 recent projects. They were split across project folders, the firm’s document control system, and the contractor’s Procore. One sizable project had only five RFIs in the firm’s own system, even though firm policy is to keep a local copy of every RFI. The rest were scattered elsewhere.
Without a system, senior reviewers are the only safeguard
When past errors aren’t synthesized and built into a system, the only way a firm uses them is through a senior reviewer who remembers. Almost every firm we talk to runs QC this way. At a small design firm in Michigan, QC is a senior architect’s page-by-page “gut check” with no formal checklist. At one of the largest firms in the country, it’s a “fresh eye” review by a senior person off the project, days before the deadline.
That puts the weight of a firm’s whole history on a few people, and it breaks down in predictable ways.
Senior reviewers don’t have the time. Schedules keep getting tighter, and a reviewer can face hundreds of potential issues across a set.
Their knowledge doesn’t fit on a checklist. One QC lead told us her team’s 200-item checklist holds everything they could think of when they wrote it. But what senior reviewers know comes from project after project, and she didn’t see how to capture it without a checklist thousands of items long.
Employees don’t stay forever. In the US, architecture and engineering workers stay with an employer for a median of 4.9 years. When a senior reviewer leaves, what they learned on past projects leaves with them.
What we’re building
Tuuli’s past errors review turns that history into a system. It runs as one loop:
Collect. Pull in RFIs, change orders, permit comments, and QC markups from completed projects through integrations with the tools firms already use, or upload them directly.
Interpret. Our platform reads each record the way a senior reviewer would and tags it by error type, cost and schedule impact, and more. Those tags let us surface the right errors on the next project.
Apply. Use the tags to match the relevant patterns to a new project, and run them as checks on its drawing set before it goes out. Each finding comes with the original error attached, so the team can see exactly why it was flagged.
The goal isn’t a searchable archive. It’s to stop the errors you’ve already seen from reaching construction again.
The cheapest error is the one you’ve already paid for
Every firm has already paid for its lessons in RFIs, change orders, and late nights. Most never get the second half of the value: making sure they don’t pay for them again.
If you’re a QC lead and the curtain wall story sounded familiar, I’d like to hear yours. Send us a few closed projects and we’ll show you which past errors are hiding in your current set.
Vit Vimal, CEO and co-founder, Tuuli