Dortech Architectural Systems Ltd is currently on site delivering a specialist glazing upgrade package for Overbury, one of the UK’s recognised fit-out and refurbishment specialists.
The project involves upgrading around 200m² of existing curtain walling, retaining the original aluminium framework while replacing the underperforming glazed elements.
A practical refurbishment strategy when the frame is still serviceable.
In simple terms, curtain walling is the glazed outer skin of a building. It is the framework of aluminium mullions and transoms that holds the glass in place and helps define the building’s appearance. On many commercial buildings, that framework can remain usable even when the glass itself is old, tired or no longer performing to modern expectations.
Where the system is still suitable, retaining it can be a sensible and efficient strategy. It avoids unnecessary full-facade removal, reduces disruption and allows building owners to improve performance without taking on a complete envelope replacement.
From an estimated 2.8 down to around 1.0 W/m²K.
The existing glass units are clear double glazing with no low-emissivity coating, with an estimated centre-pane U-value of approximately 2.8 W/m²K. A U-value measures how quickly heat passes through a material. The higher the number, the faster heat escapes. The lower the number, the better the insulation.
The new units are designed to achieve a centre-pane U-value of approximately 1.0 W/m²K, meaning significantly less heat will escape through the glazed areas. Moving from 2.8 to 1.0 represents a major improvement in thermal performance.
Better internal comfort without making the building darker.
For building owners and occupiers, this type of upgrade can improve appearance, enhance thermal performance, reduce solar heat gain and support better comfort for the people using the space.
It is a smarter way to modernise the facade: focus on the elements that drive comfort and performance, rather than treating the whole external skin as something that must be stripped out and replaced.
Better glass, explained in plain English
The new double-glazed units will be made up using 6mm Solar Control 70/35 toughened heat-soaked glass, a 16mm argon-filled cavity, a black warm-edge spacer bar, silicone seal and a 6mm clear toughened heat-soaked inner pane. That sounds technical, but the principles are straightforward.
Solar control
The outer pane helps manage how much heat from the sun passes into the building, improving comfort on sun-exposed elevations.
Argon-filled cavity
The cavity between the panes is filled with argon gas, which is less conductive than air and therefore improves insulation.
Warm-edge spacer
A better-performing edge component helps reduce cold bridging around the perimeter of the glass unit.
Toughened heat-soaked glass
The glass has been processed to improve safety, durability and resistance to spontaneous breakage.
A g-value of 0.35 helps reduce overheating while preserving natural light.
The new glass has a g-value of 0.35. A g-value measures how much solar heat passes through the glass. A lower figure means less unwanted solar heat enters the building. For offices, teaching spaces, laboratories and other occupied commercial environments, this can help reduce overheating and glare, especially on elevations exposed to strong sunlight.
Importantly, solar-control glass of this type is not about making the building darker. The aim is to maintain strong levels of natural daylight while creating a more balanced internal environment with less unwanted heat and better day-to-day comfort.
Focus on the elements that move performance forward.
This project is a strong example of how existing buildings can be upgraded intelligently. Instead of treating the whole facade as the problem, Dortech has focused on the elements that can deliver the most immediate improvement: the glass, the opening windows and the louvres.
New opening windows give building users more flexibility and can support natural ventilation strategies where appropriate. New louvres can help ventilation systems operate effectively while maintaining a clean external appearance.
Improve existing buildings rather than strip them back unnecessarily.
For Dortech, the scheme reflects a growing trend in commercial refurbishment. More clients are examining how existing buildings can be improved rather than demolished or fully stripped back. Glazing upgrades are often a practical part of that process because they can improve aesthetics, comfort and energy performance in one coordinated package.
That is exactly what makes this kind of work valuable: it is targeted, performance-led and commercially sensible, while still delivering a visible transformation to the finished facade.
Technical understanding, careful planning and aligned delivery values.
Dortech values its relationship with Overbury and the opportunity to support refurbishment schemes where technical understanding, safe delivery and attention to detail are essential.
“We are delighted to be working with Overbury on this refurbishment project. Overbury has a strong reputation for delivering high-quality fit out and refurbishment schemes, and our values are closely aligned in respect of project delivery, health and safety, quality and collaboration. This type of facade upgrade requires careful planning and technical knowledge, and we are pleased to be supporting the project with a glazing solution that improves the building’s appearance, thermal performance and internal comfort.”
A strong example of how older commercial buildings can be given a new lease of life.
By retaining the existing curtain walling and upgrading the glazing specification, this project demonstrates how older commercial buildings can be improved in a practical, cost-effective and performance-led way.
For Dortech, it is another strong example of how specialist glazing knowledge can help transform aesthetics, thermal performance and user comfort without resorting to unnecessary full-facade replacement.
