Window & Door Installation
Energy-efficient windows & quality entry doors — Family-owned, 30+ years
Energy-Efficient Windows for Ontario Homes
A-1 Siding & Windows Niagara supplies and installs custom windows for homeowners across the Niagara Region and Hamilton area. We work with Gentek, Kaycan, and other trusted distributors to supply energy-efficient windows with advanced coatings and frames designed to regulate indoor temperature year-round, reducing heating and cooling costs through Ontario’s demanding seasons.
Whether you’re replacing aging windows in Welland, upgrading a new build in Hamilton, or improving energy efficiency in Stoney Creek, we’ll help you choose windows built to handle Ontario’s climate while improving the appearance and value of your home.
Window Styles We Install
Casement Windows
Hinged on the side and opening outward with a crank, casement windows offer excellent ventilation and a tight seal against drafts — a strong choice for Ontario’s windy winters.
Double-Hung Windows
A classic style where both sashes slide vertically, offering flexible ventilation and easy cleaning. A popular choice for traditional home styles across Niagara and Hamilton.
Sliding & Bay Windows
Sliding windows offer a simple, space-saving operation. Bay windows extend outward to add light, space, and architectural character to any room.
Doors for Every Entry Point
Alongside our window installations, we offer a selection of entry and sliding doors sourced from Gentek, Kaycan, and other trusted distributors. We carry steel, fibreglass, and wood entry doors in a variety of designs and finishes, including Energy Star certified options that improve insulation and security.
- Entry Doors — steel insulated and fibreglass entry doors from Gentek, Kaycan, and other manufacturers
- Sliding & Patio Doors — vinyl and aluminum sliding and swing patio and garden doors
- Storm Doors — added weather protection for existing entry doors
Why Choose A-1 Siding & Windows Niagara?
- Over 30 years serving the Niagara Region and Hamilton area
- Family-owned and operated — you deal with the owners directly
- Energy Star certified window and door options available
- Custom sizing for replacement and new construction projects
- Proper installation and sealing to prevent drafts and moisture
- Free estimates with no obligation
Frequently Asked Questions
How do I know if my windows need replacing?
Common signs include drafts, condensation between glass panes, difficulty opening or closing, visible rot or damage to the frame, and noticeably higher heating and cooling bills. If you’re seeing any of these across your home in Niagara or Hamilton, we’re happy to take a look during a free estimate.
Are your windows energy efficient?
Yes — we offer Energy Star certified window options with advanced coatings and multi-pane construction designed to reduce heat transfer, keeping your home warmer in winter and cooler in summer.
How long does window installation take?
Most residential window replacements are completed within one to two days depending on the number of windows and any additional trim or repair work required. We’ll confirm a clear timeline before starting.
What door materials do you offer?
We carry steel, fibreglass, and wood entry doors, along with vinyl and aluminum patio doors and storm doors. Steel and fibreglass are popular for their durability and energy efficiency, while wood offers a classic, custom appearance.
Do you install both new construction and replacement windows?
Yes — we handle both new construction window installation and replacement of existing windows, with custom sizing available for either project type.
Get a Free Window & Door Estimate
Serving St. Catharines, Niagara Falls, Welland, Thorold, Grimsby, Fort Erie, Port Colborne, Niagara-on-the-Lake, Stoney Creek, Hamilton, Dundas, Ancaster, and surrounding areas.