Airdrie Retail Park – A New Shop Front Screen
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Why Secondary Glazing Works
Secondary glazing fits inside an existing window reveal, creating a separate insulating air cavity that dramatically reduces heat loss and external noise. It works with existing windows rather than replacing them, making it a highly practical upgrade for both period and modern properties across Scotland.
For listed buildings, conservation areas and properties where planning consent makes full window replacement difficult, secondary glazing is a viable and reversible solution. It preserves the external appearance of the property completely while improving thermal performance of existing glazing.
Improved Thermal Performance
Acoustic Insulation
Heritage Compatible
Reduces Draughts
- Glazing
- Security
Glass Options For Every Requirement
Choose from standard toughened glass for everyday thermal improvement, or specify acoustic laminated glass for superior noise reduction. Low-E coated glass is also available to maximise energy efficiency, and all units can be tailored to your property's specific performance targets.
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An Extra Layer of Protection
Secondary glazing creates an additional physical barrier at the window. Combined with multi-point locking hardware where specified, it provides a meaningful upgrade to the security of any room.
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Secondary Glazing Windows Gallery
The Ideal Upgrade for Period and Listed Properties
Scotland has a high proportion of listed buildings, conservation-area tenements and sandstone properties where standard double glazing is either restricted or refused by planning authorities. Secondary glazing is widely encouraged as the preferred approach, sitting inside the reveal without altering the building’s external character.
Because it is fully reversible and requires no structural changes to the window frame or surrounding masonry, it is the solution most likely to be accepted by conservation officers. We source our secondary glazing from Granada Glazing and Metal Technology – industry leaders committed to the very best quality. Century 21 has extensive experience working on both domestic and commercial properties across Scotland where heritage constraints apply.
Professionally Installed Across Scotland
Every secondary glazing system we install is measured, manufactured and fitted to the specific dimensions of your windows. There are no off-the-shelf compromises – each unit is bespoke, ensuring a tight seal, a clean finish and the best possible thermal and acoustic performance from day one.
With nearly five decades of glazing expertise behind us, Century 21 brings the same standard of workmanship to every secondary glazing project as we do to our full aluminium window and door installations. Domestic or commercial, we deliver quality that lasts.
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Our Process
Step 1
Enquiry
Get in touch with our friendly team and share the details of your project, we're happy to answer any questions and guide you through the next steps.
Step 2
Consultation & Technical Support
During our consultation, we offer technical support and work with the project architect to advise on the best systems for your project.
Step 3
Showroom Visit
Visit our showroom to see our range of products up close, and enjoy a one-to-one consultation to help find the perfect solution for your home or project.
Step 4
Quote
We'll provide a full, detailed quote tailored to your requirements, including survey and installation costs where needed, so there are no surprises.
Step 5
Installation & Aftercare
Our experienced, in-house fitting team will carry out your installation to the highest standard, with ongoing aftercare and advice available whenever you need it.
Frequently Asked Questions
Below we have answered some of the most common queries we receive from homeowners. If you can't find what you are looking for, get in touch with our team directly.
In most cases, no. Secondary glazing is a reversible internal addition that does not alter the external appearance of your property, making it acceptable to most planning and conservation authorities. We can assist with any planning permission queries and handle the process on your behalf – contact our expert team today.
Yes. Secondary glazing is actively encouraged for listed buildings and conservation area properties in Scotland, where it is often the only approved option for improving window performance without replacing original fabric.
Performance depends on the glass specified and the width of the cavity created. Contact us to discuss your specific project and we’ll be able to provide rough figures of how much noise reduction you can expect.
Yes. By reducing heat loss through your windows and eliminating cold draughts, secondary glazing can lower the thermal demand on your heating system, resulting in reduced energy consumption and lower bills over time.
Secondary glazing is available in horizontal sliding, vertical sliding, hinged and fixed configurations to suit different window types, access requirements and room layouts. At Century 21 we can recommend the most suitable system for your property. Our secondary glazing is sourced from Grenada Glazing and Metal Technology.
Visit our Showroom and See the Quality in Person
Touch the products, explore the finishes and talk to our team before you commit to anything. We’re here to help you make the right decision for your home.
10 Bairds Crescent, Allanshaw Ind Est, Hamilton, ML3 9FD
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