I ran commercial roofing operations across 15 states and touched more than 50 million dollars in projects. I have hired crews, fired crews, cleaned up other contractors' disasters, and sat across the table from every kind of operator this industry produces. So believe me when I say: the difference between a good commercial roofer and a bad one is not the price. It is whether your building survives the relationship.
The red flags, in order of how fast I would walk
- They knocked on your door after a storm and want a signature today. Urgency is a sales tactic. A legitimate commercial contractor does not need you to sign a contingency agreement in the parking lot.
- No local, verifiable history. Ask for commercial references within driving distance and actually call them. Out of state plates and a PO box are not automatically disqualifying, but they demand harder questions.
- They cannot produce insurance certificates directly from their carrier. Do not accept a PDF from the contractor. Ask their agent to send the certificate of insurance to you, naming you as certificate holder. Fakes are common and easy.
- Vague scope of work. A real commercial proposal specifies the system, the manufacturer, fastening patterns, insulation type and thickness, flashing details, and warranty terms. One page that says replace roof is an invitation to change orders.
- They want a large deposit before materials hit the site. Reasonable mobilization is normal. Half down to a company you met last week is not.
- No manufacturer credentials. Commercial roof systems carry manufacturer warranties only when installed by approved contractors. Ask which manufacturers have certified them and verify with the manufacturer.
- They offer to eat your deductible. That practice is illegal in a growing number of states and it tells you exactly how they handle paperwork.
- They speak for your insurance claim. A roofer who promises to get your claim approved is selling something they do not control, and in many states, negotiating your claim without a license crosses a legal line.
- Safety is an afterthought. Ask about their EMR, fall protection plan, and who supervises the crew daily. Blank stares mean liability lands on your property.
The documents to demand before signing
- Certificate of insurance sent directly from their agent, general liability and workers comp both
- State and local licenses where required
- Written scope with system specs and manufacturer names
- Warranty samples, both workmanship and manufacturer
- A schedule with milestones tied to payment, not payment tied to the calendar
- Lien waiver process for their subs and suppliers
The questions that expose amateurs
Ask who the foreman will be and how long that foreman has been with the company. Ask how they handle wet insulation discovered mid tearoff, and what that costs per unit. Ask what happens if rain hits an open roof. A pro answers all three without flinching, in specifics. An amateur talks in circles.
Owners are usually great at running their own business and out of their depth on a roof, which is exactly what bad contractors count on. That gap is why I built Overwatch: an owner's representative who has run these projects from the contractor side and knows where the games get played.
A word on price, because owners always ask. Get three bids when you can, but do not automatically take the low one. On commercial work, a bid 20 percent under the field usually means the contractor missed something, plans to make it up in change orders, or intends to install a thinner system than specified. Make the bids comparable: same system, same insulation, same warranty term, in writing. When bids are truly apples to apples, the spread narrows, and the conversation shifts from price to competence, which is exactly where you want it.
Vet the paper, verify the insurance at the source, demand a real scope, and never sign under pressure.