Why the humble window is at the centre of construction’s next challenge

Many construction products are having to work harder than ever before, and most will continue to do so as product legislation and building regulations tighten and the earth’s climate changes. There is perhaps no greater example of a product type having to evolve and work harder than a window.

Windows began as rudimentary openings to let natural light in and stale smells out. Openings were screened by basic timber shutters or animal skins to provide privacy and minimise weather ingress.

It was not until the first century that the Romans invented glass and used it within windows in high-status buildings. Glass was expensive and continued for many centuries to be only affordable to the wealthy.

Shelter for many was more a priority than daylight access and ventilation, so some homes historically did not have windows, and those that did often did not consider the window as an important feature. Today we simply could not design a home or most buildings without windows or glazing of some type.

Of course, human needs have not changed - we need shelter, we want to be secure and safe, we desire to be comfortable, healthy and have views out from buildings. Windows have continued to evolve to respond to all these needs and desires.

Advancements in glazing led to bigger windows. Widespread health conditions led to a realisation that ventilation was required in homes and that this could be provided by windows.

Rising living standards built expectations of greater degrees of comfort and external noise attenuation, with the response being double glazing and now triple glazing, as well as better weather and air seals. Now, in response to climate change, glazing in windows is having to minimise solar gain transmission through the glass, and it seems certain that integral shading devices will become more prevalent.

Security has always been a concern for humans, but defending windows was often not affordable to many. Window security has therefore developed in response to societal need as well as legislation, especially in recent times.

What we can be certain of is that the window will need to continue to evolve into the future

Glazing safety has been a focus over the last 150 years with the invention of toughened glass and later laminated glass, and improved safety continues to be a priority. Safe cleaning of windows and protection from falling are more recent concerns that designers have to consider.

Of course, windows and other glazing systems are essential not only for the reasons set out above but for architectural expression and the activation of facades. Windows provide delight to building users and those who use spaces around buildings.

So what is next for windows - will they have to work even harder? It seems certain that the answer is yes.

Smart windows will become more commonplace with glazing that can intelligently respond to climatic conditions to, for example, restrict solar gain within the building. Alternatively, the incorporation of integral shading systems will provide similar defensive responses, including to strong winds.

It is planned that all manufacturers will be forced by legislation to provide replacement parts for their windows to ensure longevity of the overall product. We will therefore be able to obtain like-for-like replacement ironmongery for windows.

The use of windows and glazing systems for hosting advertising imagery or film may well become more prevalent. Considering circular economy, we also need windows to have longer lives and for us to be able to reuse whole windows where they are usable.

So there needs to be overhaul services, certification and warranty services, and alternative ways of demonstrating compliance with building regulations where requirements have changed since the time of the original manufacture of the window.

What we can be certain of is that the window will need to continue to evolve into the future, and it will have to work harder than it ever has to keep building occupants comfortable, safe and secure, as well as to respond to climatic changes and resource depletion concerns.