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Aluminium COR 70 Hidden Sash Window (Style 21)
SKU: ALU-COR70-HDN-SASH-WIN-STY-21
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10 year guarantee included
7-8 weeks delivery
Sleek and contemporary, our COR 70 Hidden Sash Windows offer a minimalist finish with exceptional performance and thermal efficiency.
• Ultra-slim 66mm sightline with concealed sash
• Arch Invisible handle
• Strong, secure and low-maintenance design
2109.36
Enter Measurements *
2000mm - 4400mm
700mm - 1800mm
Please allow 10mm on either side for tolerance and 10mm tolerance for the overall height.
Mullion Width *
Mullions explained
A mullion is the point where a window panel finishes. You can customise it to suit your liking or leave it as is (for an even window panel distribution/style).
Mullions are calculated from the left of the window (in mm) and take into account the entire width of your bespoke window.
Below are examples of different window styles and from which points the mullions are calculated to and from:
2 Panel Windows
2 Panel Windows will include 1 Mullion. It will be labelled as Mullion A.
3 Panel Windows
3 Panel Windows will include 2 Mullions. They will be labelled as Mullion A and Mullion B.
4 Panel Windows
4 Panel Windows will include 3 Mullions. They will be labelled as Mullion A, Mullion B and Mullion C.
mm - mm
mm - mm
mm - mm
Mullions are calculated (in mm) from the left of the window. Minimum size: 400mm
Frame Colour*
Anthracite Grey - 7016 MATT
White - 9016 GLOSS
Black - 9005 MATT
Anthracite Grey 7016 MATT on White 9016 GLOSS
Please choose a frame colour
Glass Type*
Glass Type
Standard
Normal glass, that is clear and durable. However, when it breaks it will break into large irregular shaped shards.
Toughened
Stronger than standard glass. It is specially curated to increase strength and safety. When broken it shatters into smaller shards.
Laminated
Strongest than both standard and toughened glass. Laminated glass has a laminated layer within the sealed unit which also helps prevent damages and increases security. The laminated layer makes it increasingly difficult to break into compared to standard and toughened.
Glass Variation
Clear A Rated (Double-Glazed)
Clear A Rated (Triple Glazed)
Arctic
Autumn
Chantilly
Charcoal-sticks
Contora
Cotswold
Digital
Everglade
Flemish
Florielle
Mayflower
Minster
Oak
Pelerine
Satin
Stippolyte
Sycamore
Taffeta
Warwick
UPVC Solid Panel
Aluminium Solid Panel
Please choose a glass type
Glass Variation*
Glass Type
Standard
Normal glass, that is clear and durable. However, when it breaks it will break into large irregular shaped shards.
Toughened
Stronger than standard glass. It is specially curated to increase strength and safety. When broken it shatters into smaller shards.
Laminated
Strongest than both standard and toughened glass. Laminated glass has a laminated layer within the sealed unit which also helps prevent damages and increases security. The laminated layer makes it increasingly difficult to break into compared to standard and toughened.
Glass Variation
Clear A Rated (Double-Glazed)
Clear A Rated (Triple Glazed)
Arctic
Autumn
Chantilly
Charcoal-sticks
Contora
Cotswold
Digital
Everglade
Flemish
Florielle
Mayflower
Minster
Oak
Pelerine
Satin
Stippolyte
Sycamore
Taffeta
Warwick
UPVC Solid Panel
Aluminium Solid Panel
Clear A Rated (Standard Double Glazed)
Arctic (Standard Double Glazed)
Autumn (Standard Double Glazed)
Chantilly (Standard Double Glazed)
Charcoal-Sticks (Standard Double Glazed)
Contora (Standard Double Glazed)
Digital (Standard Double Glazed)
Everglade (Standard Double Glazed)
Flemish (Standard Double Glazed)
Florielle (Standard Double Glazed)
Mayflower (Standard Double Glazed)
Minster (Standard Double Glazed)
Oak (Standard Double Glazed)
Pelerine (Standard Double Glazed)
Satin-Opal (Standard Double Glazed)
Sycamore (Standard Double Glazed)
Taffeta (Standard Double Glazed)
Warwick (Standard Double Glazed)
Clear A Rated (Standard Triple Glazed)
Arctic (Standard Triple Glazed)
Autumn (Standard Triple Glazed)
Chantilly (Standard Triple Glazed)
Charcoal-Sticks (Standard Triple Glazed)
Contora (Standard Triple Glazed)
Digital (Standard Triple Glazed)
Everglade (Standard Triple Glazed)
Flemish (Standard Triple Glazed)
Florielle (Standard Triple Glazed)
Mayflower (Standard Triple Glazed)
Minster (Standard Triple Glazed)
Oak (Standard Triple Glazed)
Pelerine (Standard Triple Glazed)
Satin-Opal (Standard Triple Glazed)
Sycamore (Standard Triple Glazed)
Taffeta (Standard Triple Glazed)
Warwick (Standard Triple Glazed)
Clear A Rated (Toughened Double Glazed) - 4 - 20 - 4
Clear A Rated (Toughened Double Glazed) - 6 - 16 - 6
Ambi Bronze (Toughened Double Glazed)
Ambi Neutral (Toughened Double Glazed)
Ambi Blue (Toughened Double Glazed)
Ambi Aqua (Toughened Double Glazed)
Ambi Sunshade Blue (Toughened Double Glazed)
Arctic (Toughened Double Glazed)
Autumn (Toughened Double Glazed)
Chantilly (Toughened Double Glazed)
Charcoal-Sticks (Toughened Double Glazed)
Contora (Toughened Double Glazed)
Digital (Toughened Double Glazed)
Everglade (Toughened Double Glazed)
Flemish (Toughened Double Glazed)
Florielle (Toughened Double Glazed)
Mayflower (Toughened Double Glazed)
Minster (Toughened Double Glazed)
Oak (Toughened Double Glazed)
Pelerine (Toughened Double Glazed)
Satin-Opal (Toughened Double Glazed)
Sycamore (Toughened Double Glazed)
Taffeta (Toughened Double Glazed)
Warwick (Toughened Double Glazed)
Clear A Rated (Toughened Triple Glazed)
Arctic (Toughened Triple Glazed)
Autumn (Toughened Triple Glazed)
Chantilly (Toughened Triple Glazed)
Charcoal-Sticks (Toughened Triple Glazed)
Contora (Toughened Triple Glazed)
Digital (Toughened Triple Glazed)
Everglade (Toughened Triple Glazed)
Flemish (Toughened Triple Glazed)
Florielle (Toughened Triple Glazed)
Mayflower (Toughened Triple Glazed)
Minster (Toughened Triple Glazed)
Oak (Toughened Triple Glazed)
Pelerine (Toughened Triple Glazed)
Satin-Opal (Toughened Triple Glazed)
Sycamore (Toughened Triple Glazed)
Taffeta (Toughened Triple Glazed)
Warwick (Toughened Triple Glazed)
Clear A Rated (Laminated Double Glazed)
Clear Self Clean (Laminated Double Glazed)
Clear A Rated (Laminated Double Glazed Acoustic)
Clear Self Clean (Laminated Double Glazed Acoustic)
Please choose a variation colour
Trickle Vents*
What are trickle vents used for?
If this is for an extension, please read below;
All habitable rooms require 5000mm sq. of equivalent air.
If you have no other means of venting your room (i.e. a brick vent, mechanical ventilation or another window with a trickle vent fitted) then a trickle vent will need to be fitted to your window.
If this is for replacing an existing window, please read below;
If you are replacing an existing window and not changing the structural width of your opening then building regulations do not apply.
If the window you are replacing has trickle ventilation already fitted, then it is a requirement that a trickle vent is fitted on the replacement product.
You may choose to have a vent fitted regardless of if being a requirement, to aid background ventilation.
For all our aluminium windows, if you choose to have trickle vents it will be on an add-on bar (frame extension) which is 20mm high - to be added to the top of the window (this is included in the overall height of your window). On the 20mm frame extension, the trickle vent will then be cut out into it.
For all windows under 2000mm one trickle vent is fitted and for all doors over 2000mm two trickle vents are fitted.
External Cill*
External Cill
90mm Sub Cill
The drainage sub cill is found at the bottom of the frame. It protrudes out to allow the water to drip away from the brickwork. When fitted in line with the back of the frame there is a visible overhang of 17mm (for doors) and 20mm (for windows).
150mm Sub Cill
The drainage sub cill is found at the bottom of the frame. It protrudes out to allow the water to drip away from the brickwork. 150mm Sub Cill is the most standard and common sub cill used. The standard size for a normal brickwork aperture is 150mm. When fitted in line with the back of the frame there is a visible overhang of 77mm (for doors) and 80mm (for windows).
180mm Sub Cill
The drainage sub cill is found at the bottom of the frame. It protrudes out to allow the water to drip away from the brickwork. When fitted in line with the back of the frame there is a visible overhang of 107mm (for doors) and 110mm (for windows).
230mm Sub Cill
The drainage sub cill is found at the bottom of the frame. It protrudes out to allow the water to drip away from the brickwork. When fitted in line with the back of the frame there is a visible overhang of 157mm (for doors) and 160mm (for windows).
Product Notes
Description:
Room:
£
2109.36
Delivery:
FREE
7-8 weeks delivery
£
2109.36
Details
Discover our stunning Aluminium COR 70 Hidden Sash Windows, tailored to suit various budgets and designed to match a wide range of preferences.
Our Aluminium COR 70 Hidden Sash Windows offer a sleek, modern solution with all the advantages of high-performance aluminium. With a visible sightline of only 66mm, these windows provide ultra-slim framing for maximum glass exposure and a minimalist finish. Designed for modern aesthetics, the system allows the integration of the Arch Invisible handle, concealed hinges and a discreet drainage solution for an uninterrupted exterior view.
These windows are crafted with thermally broken aluminium profiles to deliver excellent structural performance and insulation. Incorporating high-performance polyamide thermal breaks and advanced draught exclusion, the COR 70 Hidden Sash system provides outstanding thermal and acoustic efficiency - reducing condensation, retaining interior warmth, and minimising external noise.
If there is a particular size you are after or a design option not provided on the site please contact us on 0203 355 5311 and our consultations team will be happy to help.
Specifications
• U Value: Double Glazed as low as 1.3 W/m²K, Triple Glazed as low as 1.0 W/m²K
• Part L: Yes
• Guarantee: 10-year warranty on factory power coating and 12 months warranty on hardware comes as standard
• Brand: Cortizo
Delivery & Returns
We at Glass Openings will carry out deliveries manufactured by us and will be free for orders that are over £1200.00. Any orders under £1200.00 will incur a delivery charge based on location.
Lead times stated at the time of ordering are not final. All delivery times are from the date we receive a finalised order, online or e-mail and when payment is made in full. Any modifications to the order will more than likely result in a delay to the delivery.
The delivery term varies by product.
Customers have a legal right to cancel orders up to seven days after the order has been placed and can receive a full refund. This statutory period of seven days does not apply on all products as the return and cancellation policy varies by product categories. As the Glass Openings store offers both bespoke and stock items, please read carefully to determine what return and cancellation policy is associated with the product you are ordering.
Please find more information on our Delivery Information & Returns and Cancellation Policy pages.
Downloads
For technical downloads and product installation manuals, please visit our Downloads page.