How this calculator reviews a change order

Who’s doing the work

The first thing you choose isn’t a number — it’s who is actually performing the added work. A general contractor working with their own crew and a subcontracted job are held to different standards: the industry ceiling sits at 20% for self-performed work and 10% for subcontracted work. That single choice sets the ceiling every later gate measures against, so it comes first.

Direct costs

Next you enter the direct cost — materials plus labor — and the total the change order actually charges. If you don’t have exact numbers yet, “Quick estimate by trade” fills in a ballpark for common trades so you can still see where things stand. It never overwrites a number you’ve typed yourself, and it’s labeled as a placeholder, not a quote.

Markup radar

Once both numbers are in, the radar shows where your markup actually sits — not as a bare percentage, but against the range the industry treats as normal for your scenario. Subcontracted work tightens the range; self-performed work allows more room. If the job is small or marked as emergency work, the range widens slightly, and the calculator says so explicitly rather than silently.

Administration fee

Some change orders carry a separate admin or project-management line. This gate checks it on its own terms — a flat $50–250 fee or 5–10% of direct cost is standard. It’s a legitimate charge, but only if it isn’t covering the same thing the markup already covers. If your markup is already on the high side and there’s also an admin fee, the calculator flags the overlap directly.

Frequency

You mark which change order this is on the project — 1st through 4th or more. From the third one onward, the calculator adds a plain-language note: repeated changes genuinely cost a crew productivity, typically 10–30%. That’s a real reason costs can drift upward. It’s not turned into a multiplier on your numbers — it’s context for the conversation, not a hidden markup of its own.

Timing

The timeline shows whether this change was requested before work started on that part of the project, while it was underway, or after. Later timing usually costs more — materials may already be ordered, finished work may need undoing — and the calculator explains why rather than just penalizing the number.

Documentation

This is where the review gets its footing. You check off what the change order actually includes: labor hours, a material list, supplier invoices, a subcontractor quote, updated drawings. The circle fills in to show how much of the total is backed by something concrete. Whatever’s missing is listed by name, because a change order that can’t be verified isn’t automatically overpriced — it’s just unverifiable, and that’s a different problem with a different fix: ask for the missing piece.

Additional context

An optional section lets you note why the change came up — an owner request, a hidden condition, a code requirement, a contractor error — along with rework level and schedule impact. None of this changes the math. It changes how the final read is worded, because a change caused by a hidden condition and one caused by a contractor’s own mistake deserve different conversations.

The Inspection Board

The result isn’t a single score. It’s a status for each gate on its own — within range, on the high end, or above standard — with the reasoning behind each one visible if you open it. A confidence line above the board tells you how much of this read is backed by real documentation versus how much is still an estimate.

Questions to ask

Based on exactly which gates raised something, the calculator writes out the specific questions worth asking your contractor — not generic ones. Copy them straight into an email or text with one click.

Before you approve it

A short checklist closes things out: the concrete items worth confirming before you sign, drawn from the same gates you just walked through.