Introduction

Hiring the right window contractor is one of the most important steps in ensuring a successful home upgrade. A high-quality installation can improve your home’s energy efficiency, comfort, and value—while a poor one can lead to costly problems. If you're a homeowner in Denver, these five questions will help you confidently vet potential installers and choose a partner who gets the job done right.

At Redline Windows, we believe in transparency, integrity, and expert craftsmanship—values we bring from our roots as a firefighter-owned and operated business.

1. Are You Licensed and Insured?

Before anything else, make sure your contractor has proper licensing and carries both liability insurance and worker’s compensation.

• This protects you if someone is injured on the job.
• Ask to see proof before signing any contracts.

At Redline Windows, we are fully licensed and insured, and happy to share documentation upfront.

2. Can You Provide References or Local Project Examples?

A reputable contractor should be proud to showcase past work. Ask to see photos or addresses of recent projects, and request contact information for past clients.

• Bonus points if they have examples in your neighborhood.
• Look for before-and-after shots and testimonials.

Check out some of our recent Denver projects to see the Redline difference in action.

3. What Brands and Materials Do You Use?

Not all windows are created equal. Ask what brands they install, whether the products are ENERGY STAR® rated, and if they offer Low-E glass, gas-filled panes, or UV protection.

• This speaks to both performance and longevity.
• Clarify whether they offer multiple frame materials like vinyl, wood-clad, and fiberglass.

Learn about our trusted energy-efficient windows and why we only use top-tier materials built for Denver’s climate.

4. What’s Included in Your Estimate?

Avoid surprises by asking what the estimate includes:

• Does it cover removal and disposal of old windows?
• What about trim work, sealing, flashing, and cleanup?
• Is the quote itemized and easy to understand?

Our window replacement process includes clear, honest pricing with everything spelled out—no hidden fees.

5. What Kind of Warranty Do You Offer?

A good contractor stands behind their work. Make sure the installation is covered by a labor warranty in addition to any manufacturer warranties.

• Ask how long the warranty lasts and what it includes.
• Be wary of vague or verbal guarantees.

At Redline Windows, we stand by every install with a satisfaction guarantee and long-term warranties you can count on.

Conclusion

Don’t take chances when it comes to your windows. Asking these five questions will help you find a window contractor in Denver who’s skilled, trustworthy, and transparent. At Redline Windows, we’re proud to serve our neighbors with the same dedication we bring to our work as firefighters.

Looking for a window contractor you can trust? Schedule your free consultation with Redline Windows today.

Find a Contractor You Can Trust

Before investing in new windows, make sure you’re hiring a professional who delivers quality and stands behind their work. Here are five key questions to ask any window contractor.