Previous Work Was Wrong: Fix vs Flag Decision Tree

Why this matters

You open up a job and find someone else's work is wrong, miswired, undersized, against code, a leak waiting to happen. Now you have a problem that isn't in your scope and a customer who hired you for something else. Handle it badly and you either take on liability that was never yours, miss a safety hazard, blow up your schedule on unauthorized work, or look like you're padding the bill. The skill is sorting fast: does this get fixed now, flagged for later, or stopped cold because it's unsafe to leave? Touching the wrong thing without authorization can transfer the blame to you. Ignoring a hazard can get someone hurt. Neither is acceptable.

Start here: is it a safety hazard right now?

This is the only branch that overrides everything else.

If it's actively dangerous (a gas leak, an electrical hazard, something that could cause a fire, flood, or injury before the customer would reasonably fix it): you cannot walk away from it silently. You don't have to repair it, but you must not leave a known hazard unaddressed and unspoken. Make it safe enough to not be an immediate danger if you can do so within your competence and authority, stop work that would energize or pressurize the hazard, and tell the customer plainly and in writing before you leave. Document that you found it and that you disclosed it. Safety disclosure isn't optional and isn't scope-dependent.

If it's not an immediate hazard, keep walking the tree.

Branch 1: Is it in the way of the job you were hired to do?

If you can't complete your scope without addressing it (the bad work is upstream of yours, or your warranty would be void if you build on it), then it's not really optional. But it's also not silent free work:

• Stop and inform the customer before you touch it. "I can't warranty my work on top of this; here's what I found and what it'll take."
• Get authorization for the added scope and price before proceeding.
• Document the pre-existing condition with photos before you change anything, so the prior defect is on record as not yours.

If your scope can be completed cleanly without touching it, go to Branch 2.

Branch 2: Flag it, don't fix it (the default for out-of-scope defects)

When the bad work is real but separate from your job and not an immediate hazard, the right move is almost always to flag, not fix:

• Document it. Photo the defect. A flag with no record is a he-said-she-said later.
• Tell the customer clearly and without trashing anybody. "Whoever did this before set it up in a way that's going to cause problems. Here's what and why." You don't need to name-call the prior contractor to make the point.
• Put it in writing on the job record. A recommendation declined is still a recommendation made. This protects you if it fails later and the customer's memory gets convenient.
• Quote the fix if they want it. Make it easy to say yes, but don't pressure. You found it, you disclosed it, the decision is theirs.

Branch 3: When NOT to touch it at all

Some prior-work defects you should explicitly leave alone unless hired:

• It's working and not a hazard, just not how you'd have done it. Style differences aren't defects. Don't re-do functional work to match your preference and bill for it; that's gold-plating with someone else's money.
• Touching it transfers liability. The moment you modify another contractor's installation, you can inherit responsibility for the whole thing. If you're not being paid to own it, don't quietly adopt it.
• It's beyond your competence or license. Flag it to the right trade. Don't dabble in work you're not qualified to warranty.

The trap on each side

Fixing too eagerly feels helpful but it's a liability magnet and a billing-trust risk. You take on someone else's mistake for free, or you look like you invented problems to pad the ticket. Flagging too timidly (or not at all) leaves hazards unspoken and customers blindsided when the prior defect surfaces, and "I noticed but didn't say anything" is indefensible after a failure.

The clean play, every time

Three moves cover nearly every case: see it, document it, disclose it. Whether you then fix it depends on hazard, scope, authorization, and competence, but the seeing-documenting-disclosing is non-negotiable regardless. A defect you found and recorded and told the customer about can never be turned into your fault. A defect you noticed and stayed quiet about can.

References

• OSHA and code-authority guidance on hazard disclosure and not concealing known dangers.
• Trade-standard practice on documenting pre-existing conditions before modifying others' work.
• See related: The Warranty Callback, Labeling and Documentation as Craftsmanship, Good Enough vs Perfect.