01
Low E Glass
Low E glass helps reflect internal heat back into the room while still allowing light to pass through. This improves the energy efficiency of the window and helps reduce heat loss.
Glass options
Double Glazed Window Glass Options
Colin’s Sash Windows supplies high performance glass options for double glazed windows, designed to improve insulation, comfort, privacy, safety, and noise reduction.
Each window can be supplied with a 24mm double glazed unit, including argon gas insulation, a warm edge spacer bar, and Low E internal glass to help improve thermal efficiency and reduce heat loss.
We also offer selected glazing upgrades, including laminated glass for enhanced safety, acoustic glazing for homes in noisier locations, and a range of obscure glass patterns for privacy.
Need help choosing the right glass?
Compare energy efficiency, privacy, safety, acoustic and design-based glass options in one clear guide.
Standard Double Glazing Specification
Our standard glazing specification includes:
- 24mm double glazed unit
- Argon gas insulation
- Warm edge spacer bar
- Low E internal glass
This combination helps improve thermal performance while allowing natural daylight into the home.
Performance features
Glass Features Explained
02
Argon Gas Insulation
Argon gas is used inside the sealed glass unit to improve insulation. It helps slow heat transfer through the glass, making the window more thermally efficient.
03
Warm Edge Spacer Bar
Warm edge spacer bars help reduce heat loss around the edge of the glass unit. They also support better overall thermal performance compared with traditional spacer systems.
04
Laminated Glass
Laminated glass is available for enhanced safety. If broken, the glass holds together rather than shattering into sharp fragments.
This makes it suitable for areas where safety, security, or breakage protection is a priority.
Privacy options
Obscure Glass Options
Obscure glass provides privacy while still allowing natural light into the room.
Available obscure glass options include:
Tip: Higher privacy levels are better suited for rooms where privacy is more important, such as bathrooms, overlooked windows and entrance areas.
Level 5Bark
Privacy Level 5
Level 5Satin
Privacy Level 5
Level 4Stipple
Privacy Level 4
Level 3Contour
Privacy Level 3
Level 3Leaf
Privacy Level 3
Level 2Westminster
Privacy Level 2
By window design
Glass Options Based on Designs
Glass options can vary depending on the window design you choose. Different frame systems support different double glazed unit sizes, laminated glass options, and performance values. This allows the glazing specification to be matched with the product design, required energy performance, safety needs, and overall project requirements.
PVCu Sliding Sash Window
PVCu sliding sash windows are available with a 24mm double glazed unit. Laminated glass can also be selected where additional safety or security is required.
PVCu Casement Window
PVCu casement windows offer a wider range of double-glazing options, including laminated glass and improved U-values, depending on the selected unit.
Aluminium Casement Window
Aluminium casement windows support a range of double-glazed units, including laminated glass options. Performance values vary depending on the glazing configuration selected.
Aluminium Flush Window
Aluminium flush windows are available with 24mm double glazed units, with laminated glass options available depending on the selected specification.
Aluminium Heritage Window
Aluminium heritage windows offer several double glazed configurations. These options allow the glazing to be matched with heritage style designs while still supporting modern performance requirements.
Full comparison
Glass Options by Window Design
Available options include:
Use the filters above to narrow the table. On mobile, each option appears as a readable card.
| Glass Unit | Laminated Glass | Performance Value |
|---|---|---|
| PVCu Sliding Sash Window | ||
| Double Glazed: 4/16/4, 24mm | No | 1.4W/m²K, ‘A’ WER |
| Double Glazed: 4/14/6.8, 24mm | Yes | 1.4W/m²K, ‘A’ WER |
| PVCu Casement Window | ||
| Double Glazed: 4/20/4, 28mm | No | 1.4W/m²K, ‘A’ WER |
| Double Glazed: 4/18/6.8, 28mm | Yes | 1.4W/m²K, ‘B’ WER |
| Double Glazed: 6/16/6, 28mm | No | 1.4W/m²K, ‘A’ WER Small Frame, ‘B’ WER Large Frame |
| Double Glazed: 6/16/6.8, 28mm | Yes | 1.4W/m²K |
| PVCu Flush Window | ||
| Double Glazed: 4/20/4, 28mm | No | 1.4W/m²K, ‘A’ WER Small Frame, ‘B’ WER Large Frame |
| Double Glazed: 4/18/6.8, 28mm | Yes | 1.4W/m²K, ‘B’ WER |
| Double Glazed: 6/16/6, 28mm | No | 1.4W/m²K, ‘A’ WER Small Frame, ‘B’ WER Large Frame |
| Double Glazed: 6/16/6.8, 28mm | Yes | 1.4W/m²K |
| Aluminium Casement Window | ||
| Double Glazed: 4/20/4, 28mm | No | 1.6W/m²K, ‘B’ WER |
| Double Glazed: 4/18/6.8, 28mm | Yes | 1.5W/m²K, ‘B’ WER |
| Double Glazed: 6/16/6, 28mm | No | 1.5W/m²K |
| Double Glazed: 6/16/6.8, 28mm | Yes | 1.5W/m²K |
| Aluminium Flush Window | ||
| Double Glazed: 4/16/4, 24mm | No | 1.5W/m²K, ‘A’ WER |
| Double Glazed: 4/14/6.8, 24mm | Yes | 1.6W/m²K, ‘A’ WER |
| Double Glazed: 6/12/6, 24mm | No | 1.6W/m²K, ‘B’ WER |
| Double Glazed: 6/12/6.8, 24mm | Yes | 1.6W/m²K, ‘B’ WER |
| Aluminium Heritage Window | ||
| Double Glazed: 4/16/4, 24mm | No | 1.6W/m²K |
| Double Glazed: 4/20/4, 28mm | No | ‘B’ WER, not new-build compliant |
| Double Glazed: 4/18/6.8, 28mm | Yes | 1.6W/m²K, ‘B’ WER |
| Double Glazed: 6/16/6, 28mm | No | 1.6W/m²K, ‘B’ WER |
| Double Glazed: 6/16/6.8, 28mm | Yes | 1.6W/m²K |
Important Note
The available glass unit, laminated glass option, and performance value depend on the product design selected. Our team can help you choose the most suitable glazing specification based on your window style, frame material, privacy requirements, safety needs, and desired thermal performance.
Choosing the Right Glass Option
The best glass option depends on the room, location, and performance you need.
For energy efficiency, the standard double glazed unit with Low E glass, argon gas, and warm edge spacer bar is suitable. For privacy, obscure glass can be selected. For additional safety, laminated glass is available. For homes affected by outside noise, acoustic glazing can be specified.
Why choose us
Why Choose Colin’s Sash Windows?
Colin’s Sash Windows provides glass options designed to improve comfort, privacy, safety, and performance. Whether you need standard double glazing, privacy glass, laminated glass, or acoustic glazing, each option can be selected to suit your home and window requirements.
Ready to Choose Your Glass Options?
Explore our range of glass options designed to improve thermal performance, privacy, safety and overall comfort. From standard double glazed units and Low E glass to Argon gas insulation, warm edge spacer bars, laminated glass and obscure privacy patterns, we can help you select the right glazing specification for your windows.
Contact us today to discuss the available glass options for your property, compare performance values, and choose the most suitable glazing solution for your requirements.
Get in Touch At Once!
Feel free to call us on 01525 552131. Our friendly sales advisors will guide you through the ordering process and help you with anything regarding double glazed windows. Alternatively, don’t hesitate to write us via the contact form or directly to our email address sales@colinssashwindows.co.uk. Don’t waste your time and take advantage of the finest quotes throughout the UK and Ireland.
