Secondary Glazing for Stone-Mullioned Windows in Warwickshire

Mr C lives in a striking period property in Warwickshire, where the original 1860s windows form an important part of the character of the building.

The windows are traditional timber casements set within substantial stone mullions. The proportions, stone surrounds and original detailing are integral to the appearance of the house.

When dealing with a traditional property of this kind, any work has to be fully sympathetic to the existing architectural elements and improvements made without altering the character of the property.

Mr C wanted to improve the performance of his heritage windows, primarily to help reduce his energy bills. To achieve this, Everest installed 26 made-to-measure aluminium secondary glazing units.

The new glazing sits internally behind the existing windows, allowing the original timber casements and external stonework to remain untouched visually.

Improving an older home without replacing the windows

When asked why he decided to make improvements to his home, Mr C was motivated “To reduce energy bills.” Period properties of this type can be draughty and difficult to heat.

For an 1860s period property like this, improving window performance isn't as simple as replacing the existing windows.

The original casements set within stone mullions are integral to the architecture of the building. The interior of the window features wooden lining with moulding details complete the architectural styling of the windows.

These are not windows you can simply replace.

Secondary glazing is the perfect solution for heritage properties and listed buildings that are limited in making changes but need to improve performance.

Why Everest?

Mr C initially found Everest through Google reviews and spoke to other companies before making a choice to go ahead with Everest based on price.

This was also a substantial home improvement project, with 26 individual units required throughout the property. The units needed to accommodate several different window configurations rather than applying the same design everywhere.

For a project of this complexity and delicacy, it needed expertise and experience to enhance the architecture and not obscure it.

Secondary glazing designed around the original windows

This property perfectly demonstrates why secondary glazing should be bespoke made.

The original windows are not a simple aperture but are divided by stone mullions, with multiple glazed sections and opening casements incorporated within the overall window. Internally, the windows are finished with moulded timber linings.

Everest used a combination of 21 vertical sliding secondary glazing units and five horizontal sliding units, selecting the opening configuration according to the individual windows to maintain ease of access.

The slim secondary frames sit inside the existing window reveals while allowing the stone-mullioned windows and surrounding timber detailing to remain the dominant architectural features. 

A noticeably quieter home

Although Mr C's main reason for installing secondary glazing was to help reduce his energy bills, another benefit became apparent first when he noticed the reduction in external sound.

Noise reduction can be an important additional benefit of secondary glazing because the new pane creates a second barrier between the room and the outside environment.

Due to the time of year, that change was noticeable first before he has been able to experience the colder months in the year.