What building owners should ask before signing a roofing contract

The best time to find out your roofing contractor subs out the whole job is before you sign, not during a leak. Most of the risk in a roof replacement gets decided in a conversation, before anyone climbs a ladder. The questions that feel awkward to ask are the ones that protect you. Ask them anyway.

TL;DR: Before signing, ask who actually performs the work, what the warranty covers and excludes, how change orders get priced, and what happens when weather stops the job. Ask for the submittals and the warranty language in writing before the contract, not after the first leak. A contractor who resents those questions has answered them.

Ask who is actually going to be on the roof

Start here. The name on the proposal and the name on the truck in your parking lot don’t have to match. Some companies self-perform with their own employees. Others sub out part of the scope, sheet metal or tear-off. And some sell the job, then hand the whole thing to a crew they haven’t worked with before.

None of those models is automatically bad. Handing specialty work to a crew that does nothing else can produce a better detail than a generalist would. What matters is knowing which one you’re buying, and getting that answer in writing before you sign.

Questions worth asking: Are the installers your employees or a subcontractor’s employees? Which portions of this scope get subcontracted? Who is the foreman, and how long has that person worked for you? How many other jobs will that foreman be running the same week? Who is on site each day, and who do I call at six in the morning when a truck is blocking my loading dock?

Insurance comes next. General liability and workers compensation certificates for the contractor, and for any subcontractor who will set foot on your building. Ask whether the policy covers the specific work being performed. Ask to be listed as a certificate holder so you get notified if coverage lapses mid project. If a contractor stalls on that request, you’ve learned something useful for the price of an email.

One more. Manufacturer certifications belong to a company, not to a salesperson. If the proposal leans on an approved or certified status, ask which legal entity holds it, and confirm that entity is the one doing the installation. A certification that sits with the seller instead of the installer won’t help you when the guarantee gets reviewed.

Ask what the warranty covers and what it excludes

“Twenty year warranty” is marketing until you read the document. There are usually two or three separate promises stacked on a commercial roof, and they fail in different ways.

The manufacturer material warranty covers the material. If the membrane itself is defective, that’s the document you use. It often says nothing about the labor to tear out and replace the failed area.

The manufacturer system guarantee, sometimes sold as an NDL or no dollar limit guarantee, is broader and usually costs more. It typically depends on the installing contractor being approved by that manufacturer, the assembly matching an approved specification, and the finished roof passing an inspection. Johns Manville’s technical, guarantee, and warranty services cover approved contractors, technical requirements, installation monitoring, final inspection, and guarantee documents. Raise those items before you sign, not after the crew loads up and leaves.

The contractor workmanship warranty covers installation defects. Ask how long it runs, what it excludes, and what happens to it if the contractor sells the business or closes the doors.

Now go hunting for exclusions. Ponding water is a common one. So is damage from foot traffic, work performed on rooftop equipment by other trades, alterations by anyone the manufacturer hasn’t approved, and failure to perform documented maintenance. Ask it straight: what actions by my staff or my other vendors would void this? Ask whether coverage is prorated over time. Ask whether it transfers if I sell the building, what that costs, and how long I have to file the transfer.

Ask to read a specimen copy of the actual warranty document during the proposal stage. Not a summary sheet. The document. If the answer is that it gets issued at completion, you can still read a specimen of the same form, and a contractor who works with that manufacturer regularly can produce one quickly.

Ask how change orders get priced before there is a change order

Every reroof has unknowns under the membrane. Wet insulation, rusted deck, a second layer nobody documented, blocking that rotted out years ago. Surprises are a given. What matters is what they cost and who decides.

Get unit pricing into the contract. Deck replacement by the square foot, priced by deck type. Insulation replacement by the board. Wood blocking by the linear foot. Additional fasteners by the count. Removal of an extra existing layer by the square. When those numbers are agreed in advance, a surprise becomes arithmetic instead of an argument.

Set the process before you need it. Who on your side can authorize additional work, and what dollar threshold requires your signature? Does work stop until you approve in writing, or can the crew keep moving to avoid leaving the deck open overnight? Both answers can be defensible. You want the answer chosen on purpose instead of discovered later.

Ask for documentation standards. Photographs of the condition before it gets covered, with the location marked on a roof plan. Quantities measured and shared the same day, not reconstructed from memory at invoicing. On time and material work, ask for the labor rate, the markup on material, and whether equipment gets billed separately.

Ask about allowances too. If the proposal carries an allowance for deck repair, ask what happens to allowance dollars you don’t spend. If unused money gets credited back, put that in the contract. If it doesn’t, you’ve just learned the real price of the job.

Ask what happens when weather stops the job

Roofing is outdoor work on the one part of your building whose job is keeping water out. A crew that opens more roof than it can close is a risk to your operation, your inventory, and your tenants.

So ask how much area gets torn off in a day relative to what the crew can dry in before they leave. Ask what dry in looks like on this specific system, and what temporary protection gets used on a partially completed section. Ask who watches the forecast and what conditions trigger a stop.

Then there’s the water that gets in anyway. Who pays for interior damage through an opened section? That answer belongs in the contract. It’s a very different conversation at two in the morning with a wet ceiling tile on your desk.

Ask how weather delays affect the schedule and the price. Are weather days built into the completion date? Does a delay trigger extended general conditions, and who absorbs that cost? If your lease or your operation has a hard deadline, ask what the contractor will commit to in writing and what happens if the date slips.

Cold weather is worth a question of its own. Some adhesives and some membranes carry temperature limits for installation. If the project runs into a Wisconsin winter, ask what the manufacturer requires at those temperatures and how the contractor plans to meet it. A guarantee issued on an assembly installed outside its limits is a fight waiting to happen.

Ask for the paperwork that backs up the answers

Talk is cheap on a roof deck in July. Documents are harder to fake.

Ask for the submittal package. Johns Manville’s commercial roofing submittal resources note that system submittals can include product data sheets, flashing details, specifications, approvals, contractor certification, and a guarantee specimen. Reading that package before you sign tells you which system you’re actually buying, how the details get built, and what the guarantee is going to say.

Ask for references from projects that are three to five years old, not the one that finished last month. New roofs look great. What you want to know is how the contractor answered the phone in year three when a detail needed attention.

Make the closeout package a named item in the contract. Final inspection documentation. The warranty certificate issued and registered to you. Notes on anything that changed from the original scope. Maintenance requirements written in plain language. Then ask what maintenance you owe to keep coverage intact, and how it has to be documented.

Ask about lien waivers. Partial waivers with each payment application, final waivers from the contractor and from suppliers and subcontractors before final payment. A contractor you paid in full whose supplier went unpaid can still become your problem.

What to take into the meeting

You don’t need to know roofing to run this conversation. You need a list and a pen. Here’s the short version.

• Are the installers your employees or a subcontractor’s? Which parts of the scope get subcontracted?
• Who is the foreman, and how many other jobs is that person running this week?
• Can I see general liability and workers compensation certificates for you and for every sub on this job?
• Which legal entity holds the manufacturer certification, and is it the entity installing my roof?
• Which warranties come with this roof, and can I read a specimen of each one now?
• What voids the warranty, is it prorated, and what does it cost to transfer if I sell?
• What are the unit prices for deck, insulation, blocking, fasteners, and an extra layer of tear-off?
• Who has to approve additional work, in what form, and does work stop until they do?
• How much roof gets opened in a day, and what does dry in look like on this system?
• Who pays for interior water damage through an opened section?
• How are weather delays handled in the schedule and in the price?
• What is in the closeout package, and what maintenance do I owe to keep coverage?

Bring the list. Ask the questions in order. Write down the answers, then compare them to the contract language you get handed a week later. The gaps between the two are the real bid comparison.

None of this takes technical expertise. It takes plain questions and attention to how they get answered. The contractor who walks you through the exclusions in their own warranty without being pushed is telling you something. So is the one who says don’t worry about that part.

Ask while you still have a choice. The best time to learn how a roofing company handles a problem is before you have one.