Estimating and Project Support
Supplement Writing for roofing contractors
A supplement is the part of a roof that nobody could see when the first scope was written. Documenting it is a timing problem before it is a writing problem.
What comes back to you
Three things, and they travel together because separately none of them carries weight. A revised line describing what the roof turned out to be. The evidence that establishes it — photographs of the condition while it was open, measurements taken from the roof as found, layer counts, decking condition. And a short written rationale attaching each to the other, so that the person reading the file does not have to reconstruct the connection themselves.
The rationale is the part most often missing. A folder of photographs and a revised total are two artifacts that a reader has to join up, and anything a reader has to work out is something they can work out differently. Writing the join is cheap when the person doing it knows what the crew found, and expensive to the point of impossible once that memory has moved on to the next job.
The window is the tear-off, not the closeout
Almost every legitimate supplement on a roof exists because opening the roof revealed something. Decking that will not hold a fastener. A second or third layer nobody counted. Flashing that turns out to be terminated into a wall rather than under a counterflashing. Rot at a valley that was invisible under intact shingle.
Every one of those is provable for a matter of hours and then, in the ordinary course of doing the job properly, permanently concealed. The crew is not doing anything wrong — they are fixing the thing they found, which is what they are there for. But the moment the new deck goes down, the justification for the line has been built over.
Which makes this desk unusual among the ones we run. Most back-office work can be caught up. This one has a hard expiry on its raw material, and a supplement written from a job whose only photographs show finished work is a supplement written from nothing. The practical answer is not more diligence at the end; it is a habit at the beginning, and a short list the crew can actually follow while standing on a roof.
Why the record is the argument
A supplement is submitted into a process that has published standards, and knowing that changes how one should be written. The Unfair Claims Settlement Practices Act, the model the states drafted their own versions from, enumerates practices that are not permitted — among them “Refusing to pay claims without conducting a reasonable investigation.”
One state’s version, cited here as a worked example of the class rather than as a statement of national law, is California Insurance Code section 790.03, which lists among unfair practices “Failing to adopt and implement reasonable standards for the prompt investigation and processing of claims arising under insurance policies” and “Not attempting in good faith to effectuate prompt, fair, and equitable settlements of claims in which liability has become reasonably clear.” Other states word it differently.
The practical consequence for a contractor is narrow and useful. A submission is evaluated against a record, so the work that matters is making the record complete rather than making the request persuasive. An item that is measured, photographed while open and tied to a stated reason does its own arguing. An item asserted without those things is asking somebody to take a contractor’s word for what was under a roof they never saw.
This describes how documentation is used and the published standards that make it matter. It is not legal advice, it makes no determination about any policy, any claim or any reader’s obligations, and the statute above is one state’s treatment rather than a national standard. Those questions belong with your own counsel.
Where this sits
Supplement writing is one desk inside Estimating and Project Support, and the boundary that governs the whole department is set out there rather than repeated here — including where preparation stops and the licensed party takes over. This page covers only what is particular to writing the supplement itself.
Questions from the field
When does a supplement actually have to be written?
At the moment the condition is open, not at the end of the job. A supplement documents something the original scope did not include, and almost everything in that category is visible for a short window — a deck condition once the shingles are off, a flashing detail once the counterflashing is pulled, a layer count nobody could see from the ground. Once it is covered up, the item still exists but the proof does not, and reconstructing it afterwards is a different and much weaker exercise.
What do you need from the crew to write one?
Photographs taken while the condition was open, with something in frame that establishes location, and a note of what was found. That is genuinely most of it. The single most common reason a supplement is thin is not that the crew failed to notice something — it is that they noticed, fixed it, and photographed the finished work rather than the condition that justified it.
Do you decide what is covered?
No, and that limit is worth stating precisely because it is narrower than it sounds. We document what was found, measure it, and write the line that describes it in the format the file uses. Whether the policy responds to that line is a coverage question, and coverage questions belong to the parties to the policy and their licensed representatives. The department page linked below sets out the wider boundary this sits inside.
What happens if the supplement is rejected?
It comes back to the record. A rejection is either about the documentation, in which case there is usually something further to attach, or it is about coverage, in which case it is not a documentation problem at all and no amount of rewriting will change it. Telling those two apart quickly is most of the value — continuing to resubmit a coverage disagreement as though it were an evidence gap wastes weeks.
Can you write supplements on jobs we have already closed out?
Sometimes, and honestly less often than owners hope. If the photographs exist and show the condition, the file can be assembled after the fact. If the only images are of completed work, there is rarely a way to establish what was underneath, and we will say so rather than write something the record does not support. The realistic answer usually arrives within a few minutes of looking at the photographs.
How is this different from writing the original estimate?
The original estimate describes a roof somebody inspected from the outside. A supplement describes what the roof turned out to be once it was opened, which means it is written against evidence that did not exist when the first scope was built. Different input, different timing, and a different failure mode — an estimate can be revised, whereas a supplement missed at tear-off is usually gone.
Documents cited above
- Unfair Claims Settlement Practices Act — National Association of Insurance Commissioners
- California Insurance Code section 790.03 — California Legislative Counsel
Send us a job with the photographs attached
One recent file is enough to show whether the crew is capturing what a supplement needs. If it is not, that is a ten-minute habit to change and worth knowing either way.