How to Choose a Commercial Roofing Contractor in NJ

Before you hire a commercial roofing contractor in New Jersey, verify five things: a current NJ 13VH registration and current insurance (liability + workers' comp), a manufacturer commercial certification like GAF GoldElite (required for the strongest warranties), real commercial references and a portfolio, a detailed written scope (system, insulation, flashing, warranty — not a one-line price), and that they survey the roof before quoting. On a commercial roof, the lowest bid rarely wins — the cost of getting it wrong is a leaking building and a voided warranty.

Green Apple Roofing holds GAF's GoldElite™ Commercial credential and has completed roughly 3,000 roofs across New Jersey since 2008. Here's what to look for, whoever you hire. (Managing residential buildings rather than a single commercial property? See apartment and multifamily roof replacement.)

Why it matters more on a commercial roof

A commercial re-roof is often a six-figure project on a building people work in every day. Get the contractor right and you get a watertight roof, a manufacturer warranty that actually holds, and minimal disruption. Get it wrong and you're looking at leaks over inventory or tenants, a warranty the manufacturer won't honor because the installer wasn't certified, and a crew that's hard to reach when something goes wrong. The stakes are why due diligence matters more here than on a house.

The 5 things to verify before you sign

1. 1Registration + insurance. Confirm the NJ Home Improvement Contractor registration and ask for current certificates of liability and workers' comp insurance. If a worker is hurt on your roof and the contractor isn't insured, that can land on you.
2. 2Manufacturer commercial certification. A credential like GAF GoldElite means the crew is trained and audited on the system and can offer manufacturer NDL warranties. Uncertified installers can't — the warranty is only as good as the certification behind it.
3. 3Commercial references and a portfolio. Ask for recent commercial jobs like yours — flat roofs, similar size — and actually call a reference or two. A real commercial roofer has a track record they're glad to show.
4. 4A detailed written scope. The proposal should spell out the system (TPO/EPDM), insulation and R-value, tear-off vs. recover, flashing and detail work, and the exact warranty. A one-line price with no scope is impossible to compare and easy to cut corners on.
5. 5A real roof survey. A serious contractor gets on the roof and takes core cuts to check for trapped moisture before quoting — not a number off satellite imagery. If they'll quote a commercial roof without seeing it, that's a red flag.

Red flags to walk away from

• No manufacturer certification — they can't offer the strongest warranties, and the crew may not be trained on your system.
• A quote without a site visit — nobody can price a commercial roof honestly from satellite imagery.
• Cash-only or a large upfront deposit — legitimate commercial contractors invoice and don't demand big money before work starts.
• No written scope or warranty — if it's not in writing, it doesn't exist.
• Modified bitumen / torch-down as the only option — single-ply TPO and EPDM outperform it; be wary of a contractor who only offers the old system.

Questions to ask on the walk-through

• Are you registered and insured in New Jersey, and can I see the certificates?
• Are you a certified commercial installer (e.g., GAF GoldElite), and what warranty does that let you offer?
• Will you survey the roof and take core cuts before quoting?
• Can you show me two recent commercial jobs like mine?
• What exactly does your written scope include — system, insulation, flashing, warranty?

How Green Apple measures up

We're a GAF GoldElite™ Commercial contractor, insured, and an NJ-registered Home Improvement Contractor #13VH11318100, with roughly 3,000 roofs across New Jersey behind us — you can see our commercial work in the project gallery. We survey every commercial roof before we quote, give you a fully itemized written scope, install single-ply TPO and EPDM (never modified bitumen), and back the work with manufacturer and workmanship warranties. If you're weighing your options first, start with our repair-vs-replace guide and cost guide. We serve building owners from Toms River to Lakewood and across the state, and we'll beat or match any reliable, legitimate roofing, siding or gutter quote.

Getting bids on a commercial roof? Request a roof survey and we'll give you a straight, itemized proposal you can actually compare.