What Time and Materials Actually Protects

Why this matters

Time and materials gets sold inside shops as the safe option: whatever happens, we get paid for it. That is not what it does. T&M does not move the risk of a job going long onto the customer. It moves the accounting of that risk, from a number you had to guess up front to a number you have to prove afterwards. Whether that trade works out depends entirely on whether the proof exists, and the proof has a shelf life measured in hours. A shop running T&M without contemporaneous daily records is in the worst position available: it carries the overrun and the argument at the same time, and it does not find out until the invoice goes out.

What T&M moves, and what it leaves with you

It moves quantity risk: the risk that the work takes more hours than anyone expected because the conditions turned out to be worse. That is a real transfer and it is worth a lot on the right job.

It leaves three risks exactly where they were.

Productivity risk stays with you, in practice if not in the contract. A slow crew bills more hours, and on paper that is fine. In reality the customer has an internal number in their head from the moment you started, and when your total passes it they stop reading your ticket and start reading your competence. The contract has no cap; the relationship does, and the relationship's cap is the one that gets enforced.

Rework risk stays with you, and should. Hours spent correcting your own error are not billable, and a T&M ticket that never shows a non-billable hour is a ticket nobody believes. This is the single most useful discipline in T&M work and almost nobody does it.

Scope definition risk stays with you. T&M tells you how the hours get counted. It does not say which hours belong to this job. Travel, mobilization, waiting for access, weather stand-downs, safety stand-downs, procurement runs: every one of those is billable or not depending on what you agreed, and if you did not agree, you will be finding out during an argument.

The artifact this whole structure rests on

A T&M job is only as good as its daily ticket. Not a timesheet, which is a payroll document, and not the final invoice, which is a summary. A ticket per day per crew, produced on site, acknowledged on site. Here is one filled in, for a fictional day on a multi-day job.

Job: Rear-of-building service riser replacement. Date: Day 4 of 6. Ticket: 4 of 6. On site: Lead tech 8.0 h, second tech 8.0 h. Total labor this ticket: 16.0 h, of which 4.0 h non-billable (see below). Work performed: Removed and replaced sections 3 and 4 of the riser. Pressure test on section 3 held. Section 4 test failed at first attempt. Non-billable: 4.0 h re-doing the section 4 joint set. First set was ours, not a site condition. Not billed. Materials used: 2 lengths, 6 fittings, 1 roll consumable. Delivery ticket 4471 attached. Delays and cause: 0.5 h waiting on building access at start, billable per agreed terms, site contact notified at the time. Conditions found: Section 4 wall thickness thinner than sections 1 to 3. Photographed, 3 images. Site contact: name, signed, time of day recorded.

Eight fields. Every one of them exists because a specific dispute happens without it: how many people, for how long, doing what, at whose cost when it went wrong, with which materials, delayed by whom, in what conditions, acknowledged by whom.

The field that changes the character of the whole document is the non-billable line. A shop that voluntarily writes off 4.0 hours in front of the customer's representative, in writing, on the day, buys credibility that no amount of arguing later can produce. It is also the only field that makes the other seven believable.

Why contemporaneous is not a style preference

A ticket written on Friday covering Tuesday is not a record. It is a reconstruction, and everybody involved knows it, including you. Two things go wrong immediately. The delays get remembered generously, because you know how the week ended. And the site contact who would have signed on Tuesday, when they could see the work, will not sign on Friday, when they cannot.

Set the standard as signed before the crew leaves the site, every day, no exceptions for short days. If the site contact is unavailable, the ticket is still completed and timestamped on site, and it is sent to them the same evening with a line asking them to flag anything they disagree with. An unanswered ticket sent that day reads far better than a signed one produced a week later, because the date is on your side and nobody has to explain the gap.

Worked example: the same job, two record sets

A six-day job, two techs, 47.5 total labor hours recorded. At invoicing, the customer's facilities manager disputes the hours, saying the crew was on site less than that and that some of the work was repeat work.

Version one: six signed daily tickets exist. The manager reads them and lands on day 4, which he thinks was slow. Day 4's ticket is 8.0 hours of billed labor. Everything else is signed, dated and unchallenged.

The dispute is now over 8.0 hours out of 47.5, which is 17% of the job. Better still, day 4's ticket already discloses 4.0 hours written off as the shop's own rework, which is exactly the concern the manager was circling. He reads it, sees the shop already took it off, and the conversation ends. Billed labor across the job is 43.5 hours, being 47.5 recorded minus the 4.0 absorbed.

Note the two figures are different currencies and do not net into a ratio: the 43.5 is hours sold, the 4.0 is hours the shop paid for and did not sell. What the write-off bought was not a percentage, it was the survival of the other 43.5 hours without a line-by-line audit.

Version two: no daily tickets, one summary invoice. The manager has nothing to check against except the total. There is no way to isolate day 4, no way to show the rework was already deducted, and no signature from anyone who was there. Now the whole 47.5 hours is in play, not 8.0. The shop's options are to discount to close it or to escalate a dispute over a job it actually performed correctly.

Watch how the exposure grew: identical work, identical hours, and the disputed amount went from 17% of the job to 100% of it, purely on the presence of a document that costs about ten minutes a day to produce. Six tickets across the job is roughly one hour of total effort against a 47.5-hour job, which is about 2% of the labor on it.

The failure mode, stated concretely. It is not that shops refuse to keep tickets. It is that they keep them for the first two days of a job, fall behind when the work gets difficult, and reconstruct the rest. Which means the tickets exist precisely for the days nothing went wrong and are missing for the days that get disputed. If you audit one thing in your T&M work, audit whether ticket density drops on the hard days.

What a cap does, and what it costs

A not-to-exceed ceiling on a T&M arrangement is a hybrid: the customer pays for actual hours up to a limit and you carry anything beyond. It is genuinely useful for winning work from a customer who cannot approve an open-ended number, and it comes with an incentive change worth naming out loud.

Under pure T&M, the crew's interest and the customer's interest are aligned on accuracy. Under a cap, the last hours before the ceiling behave like fixed-price hours, with all the compression pressure that implies. So a cap needs the same stop rule a fixed price does: verification steps are never inside the variable portion of the work. Proving dead before contact under 29 CFR 1910.333(b)(2), isolating and releasing stored energy under 29 CFR 1910.147 before opening a machine, and end-of-job leak or combustion verification are not compressible, and the crew is told that explicitly rather than left to work it out as the ceiling approaches. See related: When a Fixed Price Is the Wrong Instrument.

The other thing a cap needs is a trigger well below the ceiling. Notify the customer in writing when actual hours reach 75% of the cap, with a projection to completion. A ceiling that arrives as a surprise on the last day is a cap in name and a fight in practice.

What changes with the customer type

A commercial or institutional customer usually has a process: a purchase order, an approved rate schedule, a site contact authorized to sign tickets, and an accounts payable function that will reject an invoice without supporting documentation. Match your paperwork to their process before day one, and confirm in writing who is authorized to sign a ticket. Confirm in writing who is authorized to sign a ticket before day one. A signature from somebody who turns out to have lacked authority may buy you very little, and whether it binds the payer at all is an agency question set by state law and by the contract.

A residential customer has none of that, and the equivalent protection is frequency of contact rather than formality. Same-day tickets by message, a running total they can see, and a spoken heads-up the first time the job is trending past what you indicated.

The contract layer varies more than either. How disputed T&M invoices are handled, what prompt-payment rules apply, and what lien or bond rights you have if you are not paid are set by state law and by the contract, and several of these differ depending on whether the customer is a consumer or a business and whether the work is residential or commercial. Have your own attorney set up your T&M terms for the states you work in rather than adapting a form you were handed.

Verifying your T&M work is actually protected

• Does a ticket exist for every crew-day, produced on site the same day?
• Does any ticket in the last quarter show a non-billable line? If none do, either your crews are perfect or nobody is recording rework, and only one of those is likely.
• Does ticket completion drop off on the difficult days? Compare the last three troubled jobs against three clean ones.
• Is the person signing your tickets authorized to sign them, confirmed in writing at the start?
• Are travel, waiting, stand-downs and procurement time addressed in the agreed terms, or will they be addressed during an argument?
• On any capped job, is there a written notification at 75% of the cap, sent before the ceiling is near?

References

• See related: Time and Materials vs Fixed Bid vs Not-to-Exceed Decision Matrix; When a Fixed Price Is the Wrong Instrument; How to Price Risk You Can Name but Cannot Size
• 29 CFR 1910.333(b)(2) and 29 CFR 1910.147, cited for the verification and isolation steps that must remain outside any hour-driven compression
• Confirm prompt-payment, lien and bond rights, and any consumer-contract requirements, with your own attorney for each state you operate in; these vary by state and by customer type