Window Replacement in Longmont, CO: Built for Colorado Living, Backed by Trusted Brands

In Longmont, CO — where small-town feel meets high-altitude weather — your windows play a crucial role in protecting your home, lowering energy bills, and complementing your property’s style. At Five Seasons Windows and Doors, we install top-tier products from nationally trusted brands, professionally fitted for the demands of life along the Front Range.


Whether you live in Old Town, Prospect, or a newer development near Clover Basin, we help Longmont homeowners get more from their windows — with no pressure and no shortcuts.

Window and Door Products That Work for Longmont Homes

Longmont’s housing stock is diverse — from historic bungalows and mid-century ranches to brand-new homes in master-planned neighborhoods. That’s why we offer a wide range of pre-engineered, performance-rated windows and doors — selected from leading manufacturers and tailored to fit your home’s structure and neighborhood standards.

We install:


  • Casement, double-hung, and slider windows

  • Picture, bay, and specialty-shaped windows

  • High-performance patio and entry doors

  • Frame and grille options that align with local design guidelines

Our factory-certified, background-checked installers ensure that every product is installed to manufacturer specifications — delivering airtight seals, clean lines, and lasting performance.

Designed for Longmont’s Altitude and Climate Extremes

At over 5,000 feet in elevation, Longmont homes face intense UV exposure, high winds, snow, and temperature swings that can wear down subpar windows fast. That’s why we begin each project with a free thermal inspection, identifying where your home is losing energy and how the right window system can help.

The products we install typically feature:


  • Multi-pane glass with argon gas insulation

  • Low-E coatings to reduce solar heat gain and UV damage

  • Durable frames (vinyl, composite, or fiberglass) made to resist warping at elevation

  • Sound-dampening seals for quieter interiors near busy roads or trail systems

With improved thermal control and modern weather resistance, your home stays more comfortable — and your energy bills stay lower — all year long.

Why Longmont Homeowners Trust Five Seasons

We bring more than products — we bring clarity, professionalism, and results. Here’s what Longmont homeowners can expect from our team:


  • ✔️ Straightforward guidance — no upselling, no pressure

  • ✔️ Local experience — we know the permitting process and HOA expectations in Boulder County

  • ✔️ Skilled, non-subcontracted installers — trained and background-checked

  • ✔️ Warranties you can trust — from both the manufacturer and our own labor guarantee

Whether you're replacing aging wood windows in Old Town or upgrading vinyl units in a newer home, we deliver the same attention to detail and clean, reliable service.

Frequently Asked Questions

  • What window types are popular in Longmont homes?

    We often install casement, picture, and double-hung windows depending on your home’s layout, age, and neighborhood aesthetic. We’ll help you choose a product line that’s both functional and visually compatible.


  • Are your windows made for Colorado’s elevation and sun exposure?

    Yes. All of our recommended products are rated for thermal efficiency and UV resistance at elevation, with sealed frames and insulated glass packages built for Colorado homes.


  • How long does installation usually take?

    Most window projects in Longmont are completed in a single day. Larger homes or multi-story properties may take longer, but we’ll always outline the schedule before we begin.


  • Do you work with HOAs in newer Longmont neighborhoods?

    Yes. We’re familiar with HOA requirements in areas like West Grange and Prairie Village and can assist with documentation, color options, and finish approvals as needed.


  • What warranties come with your windows?

     All our window and door products come with a manufacturer’s warranty, and we include a separate Five Seasons labor guarantee so you’re protected on all fronts.


Upgrade Your Longmont, CO Home with Expert Window Installation

Old windows can lead to rising energy bills, drafty rooms, and faded interiors. Five Seasons Windows and Doors helps Longmont homeowners replace them with performance-driven products, clean installation, and transparent service from start to finish.


📞 Call now or click “Get a Quote” to schedule your free in-home consultation in Longmont, CO.