How does the design of aluminium window frames affect their thermal performance?

by | Jun 24, 2024 | Homeowner Advice, Resource Centre

All windows installed in the UK need to meet legal minimum requirements for thermal performance – that is, how well they keep the cold out during winter and the heat out during summer.

You can choose to go beyond the legal minimum requirements for thermal performance. A better thermal performance rating means a home with a lower carbon footprint that is cheaper to run. It’s also worth bearing in mind that thermally efficient windows also insulate against noise – which might be an important consideration if you live in a busy or noisy area.

In this blog, we’ll look at the different factors that affect the thermal performance of aluminium window frames. It will help you understand what you’re looking for when you’re exploring your aluminium window options. Your installation company will also be a valuable source of information and will be able to use their knowledge to help you choose the level of thermal efficiency that’s right for your home.

The thermal performance of aluminium windows Aluminium Window Frame

Because it is a metal, aluminium has high thermal conductivity, especially when you compare it to alternative window frame materials such as timber or PVC-U. In the past, this high thermal conductivity meant aluminium windows had a reputation for not being as thermally efficient.

However, times have changed. Today’s aluminium window frames are just as thermally efficient as their timber or PVC-U counterparts – and often more efficient.

One reason is because they make excellent use of thermal breaks. These are non-metallic sections that sit between in the inner and outer aluminium frames. These non-metallic sections form a ‘break’ between the two frames and mean that heat can’t move between them so easily.

Modern aluminium window frames also have a multi-chamber construction. Each chamber creates a pocket of air – which is an excellent insulator – helping to improve thermal performance.

The role of glazing in the thermal performance of aluminium windows

The choice of glazing is one of the biggest factors in the thermal efficiency of windows.

Double glazing provides excellent thermal efficiency. By opting for triple glazing you can take things to the next level, which is important when thermal efficiency is a critical factor in your choice of windows.

Also bear in mind the ratio between glass and frame. Glass is a much better insulator than metal, so the slimmer the frame, the better the thermal efficiency. It’s a factor that is used to excellent effect in our Evoke range of aluminium windows, which has frames that are up to 30% slimmer than competing window designs.

The importance of installation in the thermal performance of aluminium windows

Today’s engineering and manufacturing innovations mean aluminium windows are naturally very thermally efficient. But a lot of their benefits can be undone with incorrect or sub-standard installation. It’s why it’s so important to have your windows installed by experts.

For example, it’s vital that the seals and gaskets around the aluminium window frame are installed correctly. Gaps or excess material can lead to draughts that will affect the overall thermal performance of your windows. It’s also vital that your windows are a perfect fit within your window aperture. This depends on highly accurate measurements and meticulous manufacturing processes.

Experienced and expert window installation companies will understand the importance of these factors and will always be committed to delivering exceptional results that enhance and add value to your home – and improve its thermal efficiency.

Here at Capital Windows, we’ve been manufacturing and installing thermally efficient aluminium windows for over forty years. It means when you choose Capital Windows, you can be sure you’re choosing a company with expertise, experience and a commitment to excellence in every detail.

To discuss aluminium windows for your home, get in touch today.