Highest-Rated Window & Door Replacement in Colorado

It doesn’t take long at all! Most entry door installations take between 4-5 hours to complete. The process is a little faster if it’s an interior door because we don’t need to apply caulking/flashing or apply other weatherproofing measures.

The installation timeline can vary based on the products you select and the size of the job. Typically window replacement can take 6-8 weeks from initial consultation to finish, with the actual installation taking 1-2 days.

The window experts at Nex-Gen provide free in-home consultations to help you pick out the perfect windows and ensure an accurate measure so your installation gets finished on time.

Our installers come and go with minimal disruption to your routine; no need to leave your home. Our crew members receive special training and pass thorough background checks.


Upon completion, the lead installation tech does a walk-through final inspection, provides operating instructions for your new windows and doors, and reviews the warranty information.

We offer a no-questions asked, Peace of Mind Protection Warranty on almost all of our products. Unlike traditional warranties, ours lasts as long as you own your home.

This includes all fiberglass replacement products, general wear and tear, annual checkups and maintenance, and any labor to replace defective products.