Glazing is one of the most technically complex scopes on a commercial project. A bad glazing sub doesn't just produce a bad-looking building — they create inspection failures, water infiltration callbacks, certificate of occupancy delays, and warranty claims that follow a project for years. The time to vet a glazing subcontractor is before you award the scope, not after your super calls with a problem at 7am. These are the questions worth asking.
1. Are You Licensed for This Work in Florida?
In Florida, commercial glazing work requires a contractor's license — either a Certified General Contractor (CGC) or a Certified Glass and Glazing Contractor license issued by the Florida Department of Business and Professional Regulation. Before you receive a single bid from a glazing sub, verify their license is current, active, and in good standing. You can check the DBPR lookup online in under two minutes. A licensed contractor has met financial responsibility requirements and passed a state licensing exam. An unlicensed one is working illegally — and your project carries the liability. ACG holds license CGC1531993, which you can verify directly with the DBPR.
2. What Insurance Do You Carry, and Can I See a Certificate?
At minimum, a glazing subcontractor should carry commercial general liability insurance and workers' compensation coverage. Before award, request a certificate of insurance naming your company as an additional insured. Also confirm workers' comp is in place; Florida law requires it for employers with four or more employees in construction. A subcontractor who hesitates to provide insurance documentation is a subcontractor to avoid.
3. Can You Show Me Completed Projects Comparable to Mine?
Ask for photos, references, and ideally site visits to completed projects that are genuinely comparable to yours — not a portfolio of trophy projects from a different market or scale. If you're building a 50,000 SF mixed-use development, ask to see completed mixed-use projects of similar size. If you're building a healthcare facility, ask for healthcare references. A glazing sub who has completed comparable work will discuss it in specific, confident terms. One who hasn't will be vague. Browse ACG's project portfolio — including completed projects in retail, hospitality, healthcare, and multifamily — to evaluate our track record against your project type.
4. Which Manufacturers and Products Do You Work With?
The manufacturer relationships a glazing sub carries directly determine what product options are available to you. Top-tier commercial glazing systems — ESWindows, a competing fabricator, ESWindows, ES Windows — require authorized dealer relationships for technical support, warranty coverage, and a complete Division 08 scope breakdown. A glazing sub who doesn't have these relationships will be sourcing through distributors at higher cost and without direct manufacturer support. Ask specifically which manufacturers they are authorized dealers for, and verify it if the answer matters to your spec. ACG's manufacturer relationships are listed on our partners page.
5. How Quickly Can You Return a Bid After I Send Drawings?
Bid turnaround speed is a reliable proxy for project execution speed. A glazing sub who takes two weeks to price a set of drawings operates at a pace that will manifest on the job as slow RFI responses, slow submittal turnarounds, and slow resolution of field issues. A sub who can return a detailed, accurate scope within 48 hours of receiving plans is demonstrating the organizational discipline that makes projects run on schedule. When evaluating glazing subs, send drawings to multiple subs simultaneously and note who responds first — and how complete and accurate their response is. ACG returns complete scopes within 48 hours via our Scope Engine or direct submission.
6. Do You Self-Perform the Work, or Do You Sub It Out?
Some glazing contractors are primarily estimating and project management operations — they win work and then sub the field labor to whatever crews are available. This is not inherently disqualifying, but you need to know about it. Ask directly: who does the field work? Are your installers employees or 1099 subs? Does your field crew change project to project? A contractor with consistent, trained field crews delivers more predictable quality and schedule performance than one assembling ad-hoc labor. Field consistency also matters for warranty — if the installing crew changes, the institutional knowledge of your project's details goes with them.
7. How Do You Handle Change Orders?
Change orders in glazing can come from field conditions, RFI responses, design changes, or owner-directed substitutions. Ask your glazing sub how they identify and document changes, how they price them, and what their typical turnaround is on a change order request. A well-run glazing sub tracks changes in real time, provides pricing quickly, and documents clearly what's included and excluded. A poorly run sub surfaces changes weeks after the work is complete and bills for items that weren't clearly communicated — creating disputes that delay your final payment. Ask for an example of how they handled a change order on a recent project.
8. What Is Your Safety Record and Who Is Your Safety Officer?
Commercial glazing involves significant fall exposure, heavy glass handling, crane and man-lift operations, and work at elevation. A glazing sub with a poor safety record is a liability on your site — literally, for your general liability insurance, and potentially criminally if there is an incident. Ask for their EMR (Experience Modification Rate) from their workers' compensation carrier. An EMR below 1.0 indicates better-than-average safety performance. Ask who their on-site safety officer is and whether they have a written safety plan. Some GC contracts require a specific EMR threshold — know yours before you evaluate subs.
9. How Do You Manage Submittals and Shop Drawings?
On a commercial project, the glazing submittal package typically includes shop drawings, product data sheets, Florida Product Approval documentation, glass samples, and any required engineering calculations. This package must be submitted, reviewed, and approved before fabrication can begin — and fabrication lead times run 10–20 weeks for most commercial glazing products. A glazing sub who produces thorough, accurate submittals the first time keeps your schedule intact. A sub whose submittals come back with revisions — or who submits late — creates schedule compression that is difficult to recover. Ask how they manage the submittal process, who prepares the shop drawings, and what their average comment rate is on submittals.
10. What Does Your Warranty Cover and For How Long?
Glazing warranties can be complex — there's typically a manufacturer warranty on the glass and framing products, a separate warranty on the sealant work, and an installation warranty from the contractor. Understand what each covers. The manufacturer warranty on commercial glazing products is typically one to ten years depending on the product and component. Sealant warranties vary by product and installation conditions. The contractor's installation warranty typically covers workmanship for one year, though some subs offer longer. More important than the length is what the warranty actually covers and whether the contractor has a track record of honoring warranty claims. Ask for references from past clients who have made warranty claims.
How ACG Answers These Questions
ACG holds Florida license CGC1531993. We carry full commercial general liability and workers' compensation coverage. Our portfolio includes 350+ completed commercial projects across Florida — you can review comparable projects on our portfolio page. We are authorized dealers for leading commercial glazing manufacturers. We return complete scopes within 48 hours. Our field crews are experienced employees. We have a written safety program and track our EMR. Our submittal packages are prepared in-house by experienced project managers. And we stand behind our work with a clear warranty and a phone number you can actually reach.
If you're vetting glazing subs for an upcoming project in Florida, we'd welcome the opportunity to compete. Send us your plans through our contact page and we'll have a complete scope back to you within 48 hours.