Documenting a Sub's Work to Protect Yourself
Why this matters
When you hire a sub, you take on their liability under your name and their tax status on your books, and you keep almost none of the control. Documentation is what fills that gap. The photo you took at rough-in, the certificate you verified, the scope you both signed: those are the difference between recovering a loss and eating it when a defect surfaces, a customer disputes the work, or an auditor asks why you paid a tradesperson without withholding. The records cost you minutes. Their absence costs you the loss. This card is the paper trail that keeps a sub relationship from becoming your problem alone.
The record set, and what each one protects
Think of documentation as insurance you file, each piece covering a specific way a sub relationship can turn on you.
| What to capture | When | What it protects against |
|---|---|---|
| Verified certificate of insurance | Before they start | Their accident landing on your policy |
| Signed written scope and price | Before they start | "That was not in my scope" payment fights |
| W-9 on file | Before first payment | Year-end 1099 reporting and tax penalties |
| Photos at each stage | During the work | Defect disputes and hidden-condition claims |
| Written notices and replies | As issues arise | Backcharge and correction disputes |
| Payment records tied to milestones | At each pay | Overpayment and "you never paid me" claims |
| Lien waivers collected | At each pay | A sub liening your job after you paid |
Keep these together, per sub and per job, not scattered across a truck cab and three inboxes.
Verify the certificate, do not just file it
A certificate of insurance (COI) is the sub's proof that their general liability and workers comp are active. The mistake is treating the copy they hand you as protection.
- Confirm it is current, not expired, and adequate for the work.
- Note the expiration and check it again on a long or repeat engagement, because a policy that lapses mid-job leaves you exposed exactly when you assumed you were covered.
- A COI you never actually confirmed is a piece of paper that gives false confidence right up to the day you need it.
Photograph the work as it happens
Photos are your cheapest and strongest evidence, and they are only available in the moment.
- Shoot each stage, especially anything that gets covered: rough-in before the wall closes, connections before insulation, the substrate before the finish goes on. Once it is buried, you cannot re-shoot it.
- Get wide shots for context and close-ups for detail. A tight photo of a defect with nothing around it does not prove where it was.
- Photograph before any correction. If work has to be redone, the pre-fix image is what supports a backcharge later.
The pattern is evidence. If you wipe it or bury it, you cannot re-read it, and the photo is what backs your recommendation and your claim.
Keep the written trail current
Verbal agreements evaporate the moment there is money at stake. Put the load-bearing parts in writing:
- The scope and price, signed before work starts, listing what they are doing and, just as important, what they are not.
- Every change, as a short written note both sides acknowledge, not a hallway conversation.
- Every problem and every notice, with dates: what was wrong, what you asked for, what they said. This is what makes a correction or a backcharge defensible.
You do not need a lawyer for most of this. You need it written down and dated.
Get the tax and payment paperwork right
A sub is not an employee, and the paperwork proves you treated the relationship correctly.
- W-9 before the first payment, so you can issue a year-end 1099 without chasing them for a tax number after they are gone.
- Pay against invoices they submit, not timesheets you sign. Signing their hours starts to look like employment, which is a classification risk.
- Record what you paid, for what, and when, tied to completed and inspected milestones. This is your defense in a payment dispute and your backup at tax time.
Collect lien waivers as you pay
On larger or commercial work, a sub who is not paid can sometimes place a lien on the property, even a property you already paid for, if the money did not reach them down the chain. A lien waiver is their written release of that claim in exchange for payment.
- Get a waiver at each payment, matched to the amount and the through-date.
- Prefer a conditional waiver, which takes effect only when your payment clears, over an unconditional one for money not yet received.
- This keeps a sub you paid from becoming a cloud on your customer's title.
The discipline to bank
Documentation is not paperwork for its own sake. It is the only leverage you keep after you hand a sub the keys to a job under your name. Verify the insurance, sign the scope, shoot every stage, write down every problem, and collect the waivers as you pay. Do it as routine on every sub, not just the ones that feel risky, because you never know which job goes bad until the record you did not keep is the one you need.
References
- IRS guidance on independent contractors and Form W-9 and 1099-NEC reporting
- Insurance Information Institute: subcontractor liability and certificate verification
- Trade-standard practice for lien waivers and jobsite documentation
- See related: Managing a Subcontractor on Your Job; The Backcharge, and When It's Fair to Use One