5988 Mid Rivers Mall Drive #239. St. Peters, MO 63304

St. Charles Windows

The Go To, Zero-Sales Pressure Replacement Window Company in St. Charles

Beautiful, Safe, Affordable Windows From Your Local Window Depot USA

Choosing a window-replacement company in St. Charles can be a gamble. The quality of different window brands is all over the map… as is the quality of the companies installing them.

We’ve made things easy on you. We’re XteriorPRO and Your Local Window Depot USA for St. Charles. As such, we expertly install top-notch triple pane windows with cutting-edge features… and we do it for better prices.

How? Window Depot USA is a national company with ample buying power. This allows their dealers (like us) to sell their windows for an unbeatable value. As an example, we can often sell triple pane windows at the same price that other companies sell their double pane windows!

Why Choose Triple Pane Windows In St. Charles?

Our triple pane windows provide best-in-class energy efficiency, comfort, condensation resistance, and outdoor sound reduction. They are 52% more efficient than double pane windows on average, as well as 56% better at resisting condensation on the interior of the glass. You’ll also experience less outdoor noise pollution.

But our triple pane windows aren’t just better than double pane windows—they are superior to other triple pane windows, as well. Our triple pane windows come with Krypton gas between the panes instead of industry-standard Argon gas. Krypton is twice as dense, and therefore much more efficient.

We also utilize special window-installation practices that ensure the tightest and most-efficient fit (visit our Window Installation page for details). Since our installation spares no detail, we back up our work with a true Lifetime Workmanship Warranty.

And as we mentioned earlier, we can install triple pane windows on your St. Charles home for unbeatable prices—typically 30% lower than the average cost of triple pane. To ensure you get the best value, we’ve put a Price Pledge in place. If you receive a lower quote for similar products and workmanship within 30 days of signing our Price Pledge, we match the quote and give you $100.

Schedule A Free Window Quote In St. Charles Today

Contact us today to set up a convenient time for your free window quote in St. Charles. Our quotes include a comprehensive inspection of the project area, a thorough Needs Analysis, and a firm price for our services. We won’t twist your arm or play phony pricing games. You simply get the best advice and a no-nonsense price. Period.

Our Roofing, Siding & Window Services For St. Charles

Click on any of the links below to find out more details regarding our roofing, siding, and window services for St. Charles.


We install GAF roofing products and are in the 3% of roofers who are GAF Master Elite certified. We’re also one of the only Master Elite roofers in the area that utilizes Golden Pledge Warranty standards on every single job.

James Hardie Fiber Cement Siding

James Hardie fiber cement siding is the only brand of siding we install. The reason? It beats vinyl siding in all categories—from longevity to looks to durability.


XteriorPRO is the Window Depot USA for St. Charles, we offer top-of-the-line triple pane windows for unbeatable prices.

What Our Customers Are Saying…

“We had Window Depot USA replace four of our windows. The installers arrived on-time, were courteous, and completed the work promptly. The area inside and out was kept clean. We have used this company for other jobs and have always been satisfied.” -Elizabeth, St. Charles, MO 63303

Read 100 Reviews Here