Cortizo Windows: Slim, Secure and Made for Trade

Glideline offers a complete range of aluminium windows built on the proven Cortizo COR 70 system. These windows are designed for outstanding performance, with multiple configurations to suit any project. All our windows are made in-house and supplied nationwide to the trade.

We make the Cortizo range of windows, because these offer the ideal combination of aesthetics, performance, price point and specifications. They’re also ideal for residential or commercial projects.

We manufacture the complete range of Coritzo windows comprising:

Casement Windows

Our GW70 casement windows are available in both flush and standard variants. These have been designed specifically for the UK market providing a premium outward opening window.

GW70 These windows feature slim aluminium profiles and deep thermal breaks, helping achieve U-values as low as 1.3 W/m²K with double glazing and even better with triple. Sizes go up to 1800mm wide or high, one of the largest for this window type. Perfect for new builds or replacing old timber or plastic frames.

Our casement windows are the ideal product for general window replacements in dwellings or light commercial applications.

Tilt & Turn Windows

The GT70 tilt and turn system combines ventilation and easy cleaning. Tilt the sash for secure airflow or turn it fully for access or emergency escape. This inward-opening design works well in high-rise settings or where outward openings aren't practical.

Our tilt and turn range supports large sash sizes and uses concealed hinges and handles for a refined interior finish. It’s significanly better than other brands where the tilt and turn handle is often large and prominent.

Tilt and turn window provide an excellent alternative to outward opening casements and these suit any contemporary window design and where you don’t want the typical transoms and mullions. Capable of sizes up to a single door, they’re great for leading out to flat roof extensions and generally when you want the largest possible window opening.

Shaped Windows

We have invested substantially in our premises, factory machinery, staff and processes. As a result, we are expertly-placed to provde you with all manner of shaped windows.

GW70 shaped windows allow for bold architectural statements. Whether you're specifying round, arched, or triangular windows, these bespoke units are crafted to the same thermal and structural standards as our standard designs. They work well in feature areas or as part of larger glazed elements.

Our expertise and advanced manufacturing facilities enables us to provide shaped windows, including frameless corner windows and oriel windows.

Hidden Sash and Industrial Designs

For ultra-minimalist aesthetics, the COR 70 Hidden Sash offers a slimline 66mm visible section with the sash fully concealed within the frame. It’s clean and discreet, perfect for high-end residential or commercial settings.

The COR 70 Industrial model introduces a bolder frame style inspired by steel-look designs. With sash sizes up to 1600mm wide or 2600mm high, it suits large openings and gives a strong visual presence while still delivering thermal performance.

Serving Windows

Our innovative range of serving windows uses latest-generation window hardware, to provide functional and convenient windows for your business premises. Ideal for outdoor kitchens, bars, or garden rooms, Glideline serving windows are built for frequent use.

Smooth operation, safe and strong hinges, and matching aluminium profiles mean they integrate seamlessly with other doors and windows in your project. Therefore if you have a business premises needing serving windows and standard windows elsewhere in the building, we can help.

Advanced Performance with Cortizo COR 70

Our comprehensive windows collection, made for the trade, is made by us with a focus on the best possible quality, and windows designed to meet the needs of modern renovation and building projects. As such, they provide several advantages for the professional trade installer.

70mm frame depth, suitable for replacement or new build
Inward and outward opening designs
Double or triple glazed (25mm to 48mm glazing range)
U-values as low as 1.0 W/m²K with suitable triple glazing
Polyamide thermal breaks and insulated profiles
Acoustic ratings up to Rw 41 dB depending on spec
Multi-point locking systems
PAS 24 and Secured by Design options

Why Choose Glideline Windows

Cortizo COR 70 windows are well respected for their design flexibility and performance. Our in-house manufacturing ensures attention to detail, reliable lead times, and consistent product quality. Whether you need tilt and turn, casement, shaped or serving windows, the Glideline range has you covered.

We also ensure that energy performance figures are quoted accurately. We provide written proof on request, helping you meet Building Regulations and project requirements.

Contact us today to discuss your trade supply aluminium window requirements, supported by fast quotations, reliable lead times and service nationwide.

Trade Supply and Nationwide Coverage

We supply the trade with precision-made windows backed by full technical support. From large developers to local installers, our goal is to make specifying and installing premium aluminium windows easier. Our products are also available through a network of authorised showrooms across the UK.

Join the Glideline Network

Installers and trade professionals can access full product support, marketing materials, and reliable supply by becoming a Glideline partner. Whether you’re upgrading your current window offering or looking to align with a UK manufacturer, we’d like to hear from you.