The $1.2 trillion bipartisan infrastructure bill promises to retrofit hundreds of thousands of homes across the USA with new heating and cooling systems to make them more energy efficient. While certainly a commendable step, the bill doesn’t go far enough. What’s missing is a focus of building materials, which will increase efficiency yield. Here, John Mertic, area sales manager for North America at global composite materials expert Exel Composites, explores how composite materials in window and door profiles can contribute to a greener future.
According to the U.S Department of Energy, 40 per cent of all primary energy use can be attributed to the buildings sector. Another report by the Department estimates that up to 30 per cent of the energy used to heat and cool a building is lost through the windows. This means that during colder months, the money and energy to keep the building at a desirable temperature goes to waste.
Therefore, the buildings sector must tackle energy inefficiency across the entire building lifecycle. One area that contributes to a large portion of wasted energy is through a building’s windows and doors.
Stop heat escaping
To hold in heat, window manufacturers might use aluminum or polyvinyl chloride (PVC) frames with added thermal breaks. These are continuous barriers between the inside and outside window frames that prevent thermal energy loss. While effective, this insulation method requires thicker frames, which can alter the desired appearance of windows. uPVC is a superior thermal insulator compared to aluminum, but it has a higher coefficient of thermal expansion and much lower mechanics compared to fiberglass.
The combined aesthetic and functional benefits of fiberglass are increasing its popularity. Unlike aluminum, which is highly conductive, fiberglass composites are effective thermal insulators, making them the ideal candidate for window frames. The insulating properties of composite materials like fiberglass mean that there is no need for a thermal break, as the material alone can ensure thermal efficiency.
Building doors to last
Composites can also be used in door frames, as a suitable alternative to wood, which can warp, swell, and rot in damp, humid environments. As well as causing damage to the frame, this can create a draught space for warm air to escape and cold air to leak out.
PVC might be chosen in this instance, because it doesn’t expand or contract when exposed to moisture. However, it lacks the natural stiffness of wood and often requires metal reinforcements and seal bindings. Problems arise when the seal bindings are inadequately maintained, allowing more thermal energy to be lost. Therefore, companies and households might be paying the price for wasted energy and footing the bills for higher maintenance costs.
Because of its light weight and stiffness, both of which contribute to its longer service life, fiberglass is a better alternative for door frames. Fiberglass profiles do not require structural inserts, as the stiff material is manufactured in a single profile. Furthermore, fiberglass is naturally rot resistant, a property determined by choosing high performance premium grade resins, which ensures no water absorption and protection from aggressive weather conditions.
A forward-thinking approach
These mechanical properties are clearly beneficial for construction companies looking to improve the thermal efficiencies of their window and door frames. Through a process called pultrusion, fibers are pulled through a resin bath and cured in a heated die, before being cut to their desired lengths. The process is highly automated compared to manual manufacturing techniques, and ensures continuous, high-volume production of composite profiles at a consistent quality.
Exel Composites combines a local manufacturing footprint from its factory in Erlanger, Kentucky, with the expertise of a global company to provide efficient sales support and technical consultancy. The team’s collaborative approach gives engineers total design flexibility to produce window and door profiles that meet the desired aesthetic, and which help to prevent unnecessary energy losses.
So, while President Biden’s bipartisan infrastructure bill is a step towards improving the energy efficiency in buildings, it’s important that the buildings sector is incorporating the right building materials for tackling energy inefficiency.
Find out more about Exel Composites’ pultrusion expertise and composite solutions for buildings by visiting the www.exelcomposites.com/windows-and-doors today.