Ultraslim Series Vinyl Windows

The Ultraslim Series is Window Force’s modern, minimalist vinyl window — engineered to show more glass and less frame. A deeper 4-9/16″ frame is paired with a narrow 2-7/8″ visible profile and a concealed gasket, producing a clean, contemporary sightline that suits new construction, large openings, and architecturally driven designs. Every unit is custom-built to order at our 80,000 sq ft facility in Concord, Vaughan.

Ultraslim Series

More Glass, Less Frame

The slim sightline is the defining feature of the series. By keeping the visible frame to 2-7/8″ and concealing the gasket behind the profile, the Ultraslim Series maximizes the glass viewing area in every opening. The result is an uninterrupted pane that brings in more daylight, opens up the view, and gives a room a cleaner, more contemporary line — without the bulky frame and exposed rubber seals common to ordinary vinyl windows.
New Construction

Purpose-built for New Construction

The Ultraslim Series is designed for new builds and additions where the wall framing is still exposed. An optional nailing fin lets the window attach directly to the structural studs before exterior cladding goes on, giving builders and contractors a fast, repeatable install path. The deeper 4-9/16″ frame provides the structural depth larger openings demand, so the slim profile never comes at the expense of strength.

Engineering and Construction

Window Force Ultraslim Series Profile

Lead-free uPVC multi-chamber profile: the chambered interior adds rigidity and traps air for better thermal performance across the frame.

Fusion-welded corners: frame corners are heat-welded into a single continuous piece, sealing out air and water at the most vulnerable point of any window.

Dual-seal warm-edge spacer: the metal-free spacer between the panes keeps the glass edge warmer, cutting heat transfer and reducing condensation.

Hidden gasket: the weather seal is concealed within the profile for a smooth, uninterrupted surface and clean modern aesthetic.

Custom-manufactured to order: every Ultraslim window is built to the exact dimensions of your opening, from standard sizes to architectural shapes.

Glass and Glazing Options

Double Glazing

Double Glazing

Two panes of glass separated by a sealed air or gas-filled cavity

Triple Glazing

Triple Glazing

Three panes of glass separated by two sealed insulating cavities

Energy Star

Energy Star

High-performance configurations compliant with standards

Glass Coatings

Glass Coatings

Multiple glass coatings and performance options available

Available Window Styles

The Ultraslim Series can be produced across the full Window Force lineup:

Casement Casement

Tight sealing and excellent ventilation

Awning Awning

Weather-protected airflow

Single Hung Single Hung

Traditional vertical operation

Double Hung Double Hung

Traditional vertical operation. Double

Single Slider Single Slider

Space-efficient horizontal operation

Double Slider Double Slider

Space-efficient horizontal operation. Double

High Fix / Casement Fix High Fix / Casement Fix

Deliver unobstructed upper-wall light

Picture Fix / Slim Fix Picture Fix / Slim Fix

Maximum glass and unobstructed views

Bay and Bow Bay and Bow

Added space, light, and architectural depth

Shapes Shapes

Custom architectural shapes

Specifications

  Ultraslim Series Classic Series
Frame depth 4-9/16″ 3-1/4″
Visible profile (sightline) 2-7/8″ 3-1/4″
Gasket Concealed / hidden Concealed / hidden
Frame material Lead-free uPVC,
multi-chamber		 Lead-free uPVC,
multi-chamber
Corner construction Fusion-welded Fusion-welded
Spacer Dual-seal warm-edge Dual-seal warm-edge
Glazing Double- or triple-pane;
15+ glass configurations		 Double- or triple-pane;
15+ glass configurations
Best suited for New construction, large openings, modern designs Retrofit and replacement in existing homes
Installation Optional nailing fin;
available through authorized dealers and contractors		 Fits existing openings;
available through authorized dealers and contractors
Certification CSA certified;
ENERGY STAR® Partner		 CSA certified;
ENERGY STAR® Partner

Why Window Force

Window Force is a Canadian vinyl window manufacturer operating from an 80,000 sq ft production facility in Concord, Vaughan since 2007. We hold CSA certification and operate as an ENERGY STAR® Partner. Every window is custom-manufactured to order — built to your exact specifications rather than pulled from inventory — and backed by a comprehensive transferable warranty.

80K+
Square feet of
production facility
50K+
Windows manufactured
annually
450+
Active trade partners
across Ontario

We supply builders, dealers, and contractors across Canada and also accept direct homeowner orders, with professional installation available through our network of authorized dealers and contractors.

For
Home Builders

Whether you're framing a single custom home or a multi-unit residential development, Window Force provides consistent product quality, reliable lead times, and a straightforward supply-only model. Order windows to your schedule, have your crew install — no subcontracting middlemen, no installation coordination delays.

For Contractors
& Renovators

Room addition? Second-storey addition? Gut renovation with exposed framing? New construction windows give you full flexibility in rough opening sizing and placement. The optional nailing fin attaches directly to the stud framing before your cladding crew arrives — no brick moulds, no frame-in-frame compromises.

For Custom
Home Owners

Building your first or forever home? Window Force works directly with homeowners on custom builds. We help specify the right window style, glazing package, and frame configuration for every room — from large fixed picture windows in the great room to awning or casement units in kitchens and bathrooms.

For Architects
& Designers

The Ultraslim Series is available with full technical specifications, NAFS ratings, and architectural drawings for permit submissions. We work with design professionals to ensure specified windows match both performance requirements and aesthetic intent.

Frequently Asked Questions

How is the Ultraslim Series different from the Classic Series?

The Ultraslim Series uses a deeper 4-9/16″ frame with a slim 2-7/8″ sightline and hidden gasket for a modern, maximum-glass look, and is built for new construction and larger openings. The Classic Series uses a proven 3-1/4″ frame depth designed to fit into existing openings, making it the better choice for retrofit and replacement projects.

Can the Ultraslim Series be used for a replacement project?

The series is optimized for new construction, where the nailing fin can attach to exposed framing. For most retrofit and replacement work in existing homes, the Classic Series is the more suitable fit. Our team can confirm the right series once they review your opening and project type.

Does the slimmer frame reduce energy efficiency?

No. The deeper 4-9/16″ frame, multi-chamber profile, fusion-welded corners, and dual-seal warm-edge spacer all contribute to thermal performance. Paired with the right Low-E and gas-fill glazing, the Ultraslim Series meets or exceeds ENERGY STAR® requirements.

What is a hidden gasket and why does it matter?

The gasket is the weather seal that keeps air and water out. On the Ultraslim Series it is concealed within the frame rather than exposed on the surface, which produces a cleaner appearance and protects the seal from UV and weathering.

Is triple-pane glazing available?

Yes. The Ultraslim Series is available in both double-pane and triple-pane configurations, along with Low-E coatings, argon fill, tempered, laminated, and decorative privacy glass.

Trade Support

Building new or specifying for a project? Talk to our team about the Ultraslim Series. Request a custom quote online or call 905.761.2030, and we’ll confirm styles, glazing, and lead times for your build.

Windows
Types of Windows Casement Awning Single Hung Double Hung Single Slider Double Slider Shapes Bay and Bow High Fix or Casement Fix Picture Fix / Slim Fix Replacement Windows New Construction Windows
Options
Colour Finishes Jamb Sizes Exterior Casings Glass Options Brickmoulds Grills Spacers
Company
Our Manufacturing Contact Us Warranty Gallery Areas We Serve Become a Dealer Types of Windows
Blog
Misc
Window Terms Glossary Sitemap Privacy Policy Terms and Conditions
Tel: 905.761.2030
8810 Jane Street, Concord,
Vaughan, ON – L4K 2M9
Fax: 905.760.8056