Energy-Efficient Replacement Windows & Custom Exterior Doors
Lower your energy bills, improve home security, and elevate your curb appeal with precision window and door installations by Koska Construction.
Upgrade Your Home’s Efficiency and Comfort
Drafty, outdated windows and improperly sealed exterior doors account for a significant portion of lost heat during cold Minnesota winters and wasted air conditioning during the summer. At Koska Construction, we provide energy-efficient replacement windows and custom door systems designed to keep your home comfortable, secure, and quiet year-round.
Double-hung and single-hung windows
Double-hung and single-hung windows
Double-hung and single-hung windows offer a timeless appearance that fits seamlessly with traditional and contemporary home designs across Minnesota. Double-hung windows feature two operational sashes that slide vertically, allowing you to open the top, bottom, or both simultaneously to create natural ventilation currents. Single-hung windows operate with a fixed top sash and a smooth-sliding lower sash. Both styles feature tilt-in sashes, making exterior glass cleaning simple and safe from inside your home. Engineered with heavy-duty weatherstripping and insulated glass packages, these windows eliminate cold winter drafts while keeping your interior comfortable year-round.
Casement & Awning Windows
Designed for maximum energy efficiency and clear views, casement and awning windows utilize low-profile fold-away crank handles for easy operation. Casement windows hinge along the side and open outward like a door, catching fresh cross-breezes and funneling air directly into your living space. Awning windows hinge at the top and open outward from the bottom, allowing you to keep your windows open for fresh air even during light rain showers. When closed, the sashes pull tightly against the frame multi-point compression locks, creating an airtight seal that withstands high winds, heavy rain, and severe winter storms.
Casement & Awning Windows
Picture & Fixed Windows
Picture & Fixed Windows
Picture and fixed windows are non-venting glass panels engineered to maximize natural light, frame pristine exterior views, and deliver ultimate thermal performance. Because these windows do not open, they feature no moving parts or operational gaps, making them the most energy-efficient window style available. They are ideal for high ceilings, living rooms, and scenic lakefront views across the Brainerd Lakes region where maximum daylight is desired. Picture windows can also be paired with operational casement, awning, or double-hung windows to create custom multi-window combinations.
Bay & Bow Windows
Bay and bow windows add dramatic architectural character, increase natural interior lighting, and physically expand your indoor living area. A traditional bay window features three panels set at sharp angles (typically 30 or 45 degrees), creating a deep interior ledge perfect for cozy window seats or decorative displays. Bow windows feature four, five, or six continuous panels arranged in a gentle curve for a sweeping view of your landscape. Built with custom head and seat boards and fully insulated framing, our bay and bow installations combine dramatic curb appeal with heavy-duty structural integrity.
Bay & Bow Windows
Sliding Windows
Sliding Windows
Sliding windows operate on smooth horizontal tracks, making them an ideal choice for areas where exterior clearance is limited or opening a vertical sash is difficult. Featuring slender frame profiles and expansive glass areas, sliding windows provide unobstructed views and effortless one-handed operation. They are commonly installed above kitchen sinks, in short walls, or along walkways and patios where an outward-swinging window could create an obstruction. Built with durable brass rollers and removable sashes, our horizontal sliders deliver long-term operational ease and tight weather protection.
Entry, Patio & Storm Doors
Your entry doors play a central role in home security, thermal performance, and curb appeal. We install high-end exterior doors built to perform flawlessly against the elements:
Entry Doors
Choose from heavy-duty steel or insulated fiberglass entry doors with custom glass inserts, decorative hardware, and reinforced security strikes.
Patio Doors
Choose from heavy-duty steel or insulated fiberglass entry doors with custom glass inserts, decorative hardware, and reinforced security strikes.
Storm Doors
Choose from heavy-duty steel or insulated fiberglass entry doors with custom glass inserts, decorative hardware, and reinforced security strikes.