Glazing is one of those scopes where a bad sub can hurt you in ways that don't show up until it's too late to recover. Here's how to evaluate glazing contractors before you're committed to one.
The Basic Qualification Checklist
Before getting into the nuanced evaluation, there are basics that every commercial glazing sub should be able to demonstrate:
- Florida Certified Glazing Contractor license — Required by the state. No license, no bid.
- Certificate of insurance — Current general liability, workers comp, and umbrella coverage at appropriate limits for your project size.
- Financials strong enough to carry the project — Glazing subs that can't carry their material costs become your problem when material vendors put holds on deliveries.
- Comparable project experience — A sub that's great at retail storefront may struggle on a 20-story window wall project.
The Submittal Question
The single most revealing question you can ask a glazing sub before awarding a contract is: "Walk me through your submittal process."
A good sub can describe, in specific detail, how they prepare shop drawings, who reviews them internally, what their typical submittal timeline is, and how they manage revision cycles. They should also be able to describe what a complete HVHZ submittal package looks like if your project is in a wind-borne debris region.
A bad sub gives vague answers, can't tell you how long their submittal process takes, or says something like "we just send in what the manufacturer gives us." Their submittals will be incomplete. They will come back from plan review with multiple correction cycles. And every revision cycle costs you two to three weeks on your schedule.
Ask About Their Material Lead Times
Florida glazing subs deal with the same supply chain constraints that every construction trade faces — but the consequences of a missed material delivery are particularly acute. If the glass isn't on site when the installation crew is scheduled, you're losing that crew's time and rescheduling other trades that were supposed to follow.
A good sub tracks their material orders proactively and communicates status to the GC before problems develop. They should be able to tell you, at any point in the project, exactly where every material order stands and when it's expected on site.
Ask the candidate sub: "How do you handle material delays?" If the answer is "we hope they don't happen," find a different sub.
The Trade Coordination Test
Glazing sits at the interface of multiple other trades — waterproofing, framing, drywall, mechanical, and structural. How a glazing sub approaches these interfaces is a reliable predictor of their overall professionalism.
Red flags:
- Sub that expects the GC to coordinate with other trades on their behalf
- Sub that can't produce coordination drawings showing interfaces with adjacent systems
- Sub that doesn't ask about waterproofing sequence during the buyout process
- Sub that shows up expecting other trades to accommodate them without prior coordination
Good subs proactively identify the coordination requirements, reach out to adjacent trades early, and produce the documentation needed to resolve conflicts before they happen in the field.
Check Their Reference Projects
Ask for three to five references from comparable projects — similar size, similar system type, similar market. Then actually call the references.
Specific questions to ask references:
- "How was their schedule performance? Did they hit the milestone dates they committed to?"
- "Were there significant change orders? Were they legitimate or was scope missing from the original bid?"
- "How responsive was their project management team?"
- "Would you use them again?"
The last question is the most important. A glazing sub that GCs use once and never hire again is telling you something important.
What ACG Brings
ACG was built specifically because GCs needed a glazing sub that executes like they do. We answer the phone. We submit shop drawings when we say we will. We coordinate proactively with your other trades. We commit to dates and hit them.
Our references are GCs who've used us on multiple projects — because the first project went well enough that they didn't want to take a chance on a new sub. If you're evaluating glazing contractors for an upcoming project, we'd welcome the conversation. Send us your plans and we'll show you how we approach a scope.