Window Replacement & Installation in the Tri-State Area
Energy-efficient windows installed by Thermo-Seal’s full-time, in-house team—never subcontractors. Trusted since 1985.
- Andersen Certified Contractor + premium brands (Andersen, Pella, Harvey)
- Most standard installs completed in as little as one day (project dependent)
- 5.0 Google rating + 99% satisfaction rate
- 0% interest financing available
"At Thermo-Seal, we believe every home deserves windows that are energy-efficient, stylish, and built to last. Our expert installations combine premium brands with superior craftsmanship—delivering comfort, beauty, and long-term value."
A+ Rated Window Company Serving Westchester, Rockland, Suffolk, Nassau & Fairfield Counties
Window Services: Replacement & Installation
Replacement Windows
If your current windows feel drafty, look dated, or are impacting comfort, replacement windows can make a noticeable difference. Thermo-Seal helps Tri-State homeowners improve indoor comfort, support lower energy bills, and refresh curb appeal with energy-efficient options built to fit.
Window Installation
For renovations, additions, or upgrading specific rooms, professional window installation ensures a tight fit and dependable performance. Thermo-Seal window installation is completed by our full-time, in-house team—never subcontractors—so quality stays consistent from start to finish.
Window Styles
Not sure what type of window fits your space best? Explore popular options—from bay and bow to casement and double hung—to find the right balance of ventilation, light, and aesthetics for your home.
• Window Styles •
Energy-Efficient Windows for Homes in the Tri-State Area
Windows from Thermo-Seal can be designed to fit virtually any opening and are available in vinyl, wood, or composite. Choose from our most popular window styles, or let us know if you're looking for something custom.
Bay and Bow Windows
Beautifully designed & energy efficient, these windows are the perfect addition to any living room.
Casement Windows
Achieve maximum ventilation & clear views with the simple turn of a handle.
Double Hung Windows
These classic windows look great in any home, offering upper and lower sashes they are one of our most versatile models.
Garden Windows
A garden window is perfect for any kitchen & a perfect way to keep plants healthy.
Picture Windows
These windows fill any room with sunlight & offer unobstructed views of the beautiful outdoors.
Sliding Windows
Allow plenty of natural light in with these easy to open contemporary windows.
Your Questions, Answered
Frequently Asked Questions
What’s the difference between window replacement and new window installation?
Window replacement typically means removing an existing window and installing a new unit in the same opening, often using the existing frame when appropriate. New window installation is commonly part of a remodel, addition, or layout change and may involve reframing or creating a new opening to fit the project goals.
How much does window replacement cost in NY/CT/NJ?
Window replacement cost depends on factors like window size, style, material (vinyl, wood, or composite), brand selection, and the condition of the existing opening. Thermo-Seal offers a free in-home estimate to review your home and recommend the best options, and 0% interest financing is available to help make your project more manageable.
How long does window replacement or installation take?
Timelines vary based on the number of windows, window type, and any unexpected conditions found during removal. Most standard installs are completed in as little as one day (project dependent), and your estimator will walk you through what to expect for your specific home.
Do you use subcontractors for window installation?
No—Thermo-Seal window installation is completed by our full-time, in-house team, never subcontractors. That means consistent workmanship, clear communication, and accountability from start to finish.
What window materials are best: vinyl, wood, or composite?
The best window material depends on your goals for maintenance, appearance, and performance. Vinyl is popular for durability and low upkeep, wood offers a classic look, and composite balances strength with energy-efficient performance—Thermo-Seal will help you compare options during your consultation.
What window brands do you install (Andersen, Pella, Harvey)?
Thermo-Seal installs premium window brands including Andersen, Pella, and Harvey. We’ll help you choose the right product line based on your home’s style, performance needs, and budget during your free in-home estimate.
What are signs I need replacement instead of repair?
If you’re feeling drafts, seeing condensation between panes, struggling to open/close windows, noticing visible damage, or dealing with rising energy bills, replacement may be the better long-term solution. Windows that are 15–20 years old or older may also lack modern energy-efficiency features, so an evaluation can clarify the best next step.
Do new windows improve energy efficiency?
Yes—new, energy-efficient windows can reduce drafts and heat transfer, helping your home stay more comfortable year-round. The biggest improvements typically come from pairing quality window products with professional installation for an airtight, properly sealed fit.
How do I know when it's time to replace my windows?
Signs that you may need window installation or replacement include drafts, rising energy bills, difficulty opening or closing windows, visible damage, or condensation between panes. If your windows are 15–20 years old or older, they may also lack modern energy-efficiency features. During your consultation, Thermo-Seal will assess your current windows and help you determine the best solution based on performance, appearance, and cost.
What types of windows does Thermo-Seal install?
We install a wide variety of energy-efficient window styles, including double hung, casement, sliding, bay, bow, garden, and picture windows. Each style is available in materials like vinyl, wood, or composite to suit your home’s architectural needs and personal preferences. Whether you’re looking for better airflow, larger views, or a custom look, we’ll help you choose the right window styles for your space.
Schedule an Appointment
Contact us through our contact form and we’ll get back to you as soon as we can.
Windows
services we provide
Professional Exterior Remodeling Services
Windows
Enhance your home with energy-efficient windows from Andersen, Pella, and Harvey. Our expert installations improve comfort, reduce energy costs, and add timeless beauty to your living spaces.
Siding
Protect and beautify your home with durable siding solutions. We install fiber cement, vinyl, and wood siding for lasting performance, improved curb appeal, and energy efficiency.
Roofing
Safeguard your home with premium roofing systems. From GAF asphalt shingles to metal and tile roofing, our certified experts deliver strength, durability, and long-term weather protection.
Doors
Upgrade your entryways with stylish, secure doors from Therma-Tru and other leading brands. Our installations enhance curb appeal, improve security, and provide lasting performance for your home.
Gutters
Keep your home protected with seamless gutter systems designed to prevent water damage. Our expert installations ensure durability, efficiency, and reliable protection for your roof and foundation.
Certified. Trusted. Proven.
With Thermo-Seal, you receive expert craftsmanship and trusted credentials. We partner with top manufacturers and hold certifications to provide the best products. As a licensed and insured company, we safeguard your investment.
Our Edge.
Why Choose Thermo-Seal for Your Windows?
Rely on Thermo-Seal to provide a window that’s maintenance free, durable, airtight, and energy efficient. Contact us today for a custom window plan that will bring comfort, beauty, and satisfaction to your family year after year.
Professional Installation
When you hire us for your replacement windows you will be working with a professionally trained and well experienced company. Our installers are fully trained and insured.
Customer Care
Client satisfaction is our top priority. We ensure high-quality, accurate work. You'll never be disappointed! We are highly rated on home improvement review sites and appreciate all the positive feedback!
Andersen Certified Contractor
We have been vetted, trained, and backed by Andersen Windows & Doors, the industry's #1 most trusted and recommended brand of window and doors.
Experience the Thermo-Seal Difference
Reliable Exterior Remodeling in the Tri-State Area
Real Stories, Real Feedback
Our Client Reviews
Aaron and his team were fantastic! Our windows were ready 2 weeks earlier than expected and his team was always on time. They were pleasant to have around, were respectful of our space and cleaned up after themselves. We had a problem with rot in one of our walls and Aaron and his team helped us to fix it as part of the window installation, including finding a great electrician at the last minute. Thanks, Thermo-Seal! We're very pleased.
Rachel R.
I had a very good experience with Thermo Seal. Chose them after interviewing many others bc they're local, communicated efficiently and offered good midrange pricing + lifetime warranty. Aaron was great to work on setting up the contract and and then Fabio and his crew did a fantastic job with the installation. They came early, they finished 5 windows in 4-5 hours, they cleaned up. Fabio even helped me take care of another issue he found on the roof. Highly recommended.
Patryk B.
We Replace and Install Windows in New York, New Jersey and Connecticut
Thermo-Seal proudly provides Window Replacement and Window Installation throughout New York, New Jersey and Connecticut. From Nassau County, Suffolk County, Rockland, and Westchester to Bergen and Fairfield County and the greater areas of Connecticut.
Our experts are available in dozens of local communities, providing the highest level of service in the industry as we've been around for over four decades with a reputation you can trust.
