20 Questions to Ask Your Window Installer Before Signing

Replacing your windows is a significant investment, and the installer you choose matters just as much as the product. A great window installed poorly will leak, draft, and fail years before it should. A good window installed by a skilled professional will perform beautifully for decades.

Before you sign a contract, ask these 20 questions. The answers will tell you whether you're working with a company that stands behind its work — or one you should walk away from. For a broader look at evaluating window companies, see our guide on how to choose a window company.

Licensing & Insurance (Questions 1–4)

1. Are you licensed and registered in my city?

Why it matters: While Texas does not have a statewide contractor license requirement, many DFW cities require contractor registration and building permits for window replacement. An installer who isn't aware of local requirements may cut other corners too.

Good answer: "Yes, we're registered in [your city] and will pull all required permits for your project."

2. Do you carry general liability insurance?

Why it matters: General liability insurance protects you if the installer damages your home during the project. Without it, you could be personally liable for repairs.

Good answer: "Yes, we carry $1 million or more in general liability coverage. Here's our certificate of insurance."

3. Do you carry workers' compensation insurance?

Why it matters: If a worker is injured on your property and the company doesn't have workers' comp, you could be held liable. This is non-negotiable.

Good answer: "Yes, all of our employees are covered by workers' compensation." Ask to see the certificate.

4. How long have you been in business?

Why it matters: Experience matters, and longevity is a sign of reliability. A company that's been around for several years is more likely to be around to honor its warranty.

Good answer: A specific number of years, along with a history of serving the DFW area. Beware of companies that have been "in the industry" for years but recently started a new company — that could mean they restarted under a new name to escape a poor reputation.

Products (Questions 5–9)

5. What brands of windows do you offer?

Why it matters: Reputable companies carry name-brand windows from established manufacturers. Be wary of companies that sell only their "own brand" — these are often generic windows rebranded with a private label, making it impossible to compare them to competitors.

Good answer: Named, recognizable brands with a strong reputation. At Bradley James Windows & Doors, we carry Andersen, Anlin, and ProVia — brands you can research independently.

6. Are these windows Energy Star certified for our climate zone?

Why it matters: Not all Energy Star windows qualify for every climate. DFW falls in the South-Central zone, which has specific U-factor and SHGC requirements. Windows certified for a northern climate may not meet the South-Central zone standards.

Good answer: "Yes, every window we offer is Energy Star certified for the South-Central climate zone."

7. What glass package is included in the quoted price?

Why it matters: The glass package (number of panes, Low-E coatings, gas fill) accounts for most of the window's energy performance. Some companies quote a base price with minimal glass features and then add Low-E and gas fill as expensive upgrades.

Good answer: The quote should clearly specify dual-pane or triple-pane glass, Low-E coating type, and argon or krypton gas fill. These features should be standard, not add-ons. Learn more about what to look for in our best windows for Texas heat guide.

8. Can I see the NFRC label or performance ratings for this specific window?

Why it matters: The National Fenestration Rating Council (NFRC) label provides independently tested performance data including U-factor, SHGC, visible transmittance, and air leakage. If a company can't provide these ratings, you have no way to verify their energy efficiency claims.

Good answer: "Absolutely, here are the NFRC ratings for the specific product we're quoting." They should be happy to share this information.

9. What frame material options are available?

Why it matters: You should understand whether you're getting vinyl, fiberglass, wood, or another material, and why it's recommended for your situation. Each material has different durability, appearance, and cost characteristics.

Good answer: A clear explanation of the available materials and an honest recommendation based on your home, budget, and priorities.

Installation (Questions 10–14)

10. Do you use your own employees or subcontractors?

Why it matters: This is one of the most important questions you can ask. Companies that use their own W-2 employees have direct control over training, quality, and accountability. Subcontracted crews may be fine, but the window company has less oversight and you have less recourse if something goes wrong.

Good answer: "We use our own trained, full-time installation teams." At Bradley James Windows & Doors, every installation is performed by our own crew.

11. Is it a full-frame replacement or an insert (pocket) installation?

Why it matters: Full-frame replacement removes the entire old window including the frame, giving you maximum glass area and the opportunity to inspect and repair the rough opening. Insert installation fits a new window inside the existing frame, which is less disruptive but reduces glass area and assumes the old frame is in good condition.

Good answer: The installer should explain which method they recommend for your situation and why, not default to one approach for every home.

12. How do you handle the interior and exterior trim?

Why it matters: Window replacement affects the trim and casing around each opening. You need to know whether the installer will reuse existing trim, install new trim, or leave unfinished edges for you to deal with.

Good answer: A clear explanation of what's included: new interior and exterior trim, caulking, and a finished, clean appearance upon completion.

13. How do you seal and insulate around the new window?

Why it matters: The gap between the window frame and the rough opening must be properly sealed and insulated. Poor sealing is one of the most common installation failures and leads to air leaks, water intrusion, and energy loss.

Good answer: "We use low-expansion spray foam insulation around the perimeter, followed by interior and exterior caulk, and flashing to prevent water intrusion."

14. How long will the installation take, and what should I expect on installation day?

Why it matters: Knowing the timeline helps you plan. A typical whole-home window replacement takes one to two days. Understanding the process reduces stress and sets proper expectations. See our window installation process guide for a full walkthrough.

Good answer: A specific timeline and description of the process, including how they protect your home's interior, how they handle debris, and what the cleanup looks like.

Warranty (Questions 15–17)

15. What does the manufacturer's warranty cover, and for how long?

Why it matters: Manufacturer warranties cover defects in the product itself. The best warranties are lifetime, transferable, and cover parts, glass, and hardware. Read the fine print — some "lifetime" warranties have significant limitations after the first 10 years.

Good answer: A specific description of coverage periods for frame, glass, hardware, and seal failure. The installer should be able to provide a copy of the warranty document for your review.

16. Do you offer a separate workmanship (labor) warranty?

Why it matters: The manufacturer's warranty covers the product, but installation defects (improper sealing, flashing, or fit) are typically not covered by the manufacturer. A reputable installer should stand behind their work with a separate labor warranty.

Good answer: A clear, written labor warranty of at least 5 years, with 10+ years being ideal. The warranty should cover coming back to fix any installation-related issues at no charge.

17. Is the warranty transferable if I sell my home?

Why it matters: A transferable warranty adds value to your home when you sell. Buyers appreciate knowing the windows are covered, and it can be a selling point that sets your home apart.

Good answer: "Yes, both the manufacturer warranty and our labor warranty transfer to the new homeowner."

Pricing (Questions 18–20)

18. Is this a firm quote, and what exactly is included?

Why it matters: Your quote should be a fixed price that includes everything: windows, installation, trim, sealing, insulation, hardware, screens, cleanup, and debris removal. Beware of quotes that leave room for "additional charges" after the project starts.

Good answer: "This is a firm, all-inclusive price. There are no hidden fees or surprise charges." The quote should be itemized so you can see exactly what you're paying for.

19. Do you offer financing?

Why it matters: Window replacement is a significant investment, and many homeowners benefit from spreading the cost over time. Quality financing options with reasonable rates make the project more accessible.

Good answer: "Yes, we offer financing with multiple term lengths and competitive rates. We can walk you through the options during your consultation."

20. What is your deposit and payment structure?

Why it matters: Understanding when payments are due protects you. A reasonable deposit (10 to 30 percent) at signing is normal for custom orders. The balance should be due upon satisfactory completion of the installation.

Good answer: A clear, written payment schedule with no more than 30 percent due at signing and the balance due at completion. Run from any company that demands full payment before work begins.

Red Flags to Watch For

During your interactions with window companies, watch out for these warning signs:

• High-pressure sales tactics: "This price is only good today" or "I need to call my manager for a special deal." Reputable companies give you time to decide.
• Unable to provide references or reviews: A company with a solid track record should have plenty of verifiable reviews and be willing to share references.
• No written contract or vague terms: Everything should be in writing — products, timeline, price, warranty, and payment terms.
• No physical business address: Companies operating out of a P.O. box or with no verifiable office may be fly-by-night operations.
• Dramatically lower price than other quotes: If one bid is 40 percent below everyone else, they are likely cutting corners on products, installation, or both.
• Unwillingness to answer questions: If a salesperson becomes evasive, defensive, or dismissive when you ask these questions, that tells you everything you need to know.
• No insurance certificates on request: Any legitimate company can produce insurance certificates within minutes. Refusal or delay is a deal-breaker.

Why Homeowners Trust Bradley James Windows & Doors

We welcome every question on this list — and any others you can think of. As a veteran-owned company serving the DFW area, we believe in transparency, honest pricing, and standing behind our work. Here's what you'll find when you work with us:

• Name-brand products from Andersen, Anlin, and ProVia that you can research independently
• Our own trained installation crews — no subcontractors
• Written warranties on both products and workmanship
• Straightforward, all-inclusive pricing with no hidden fees
• First responder and military discounts to honor those who serve
• Flexible financing options for every budget

Request your free estimate or contact us to schedule your in-home consultation. We'll answer every question and help you make the best decision for your home.