Thermally broken skylights
The BIG question

All of the industry leading rooflights we manufacture in-house at Sunsquare are made using a lightweight aluminium framework which saves a considerable amount of weight – both for transportation and the stress on a property’s overall structure. Furthermore, it’s a very strong and durable material, requiring minimal maintenance during years of use.

Combating aluminium’s conductive properties

Nevertheless, the one drawback of using aluminium frameworks for our BSI Kitemarked flat roof skylights is that aluminium is a very effective conductor of heat. Consequently, the framework can become a very large area of heat loss in colder, winter months, with heat generated internally transferred outside via direct transfer through the rooflight framework.

In addition, if a rooflight is installed above a living space where humidity levels are somewhat higher than usual e.g. a bathroom or kitchen-diner, condensation risks forming on the inside of the aluminium framework. For rooflights without a thermal break, the humid air touches the cold surface of the aluminium frame and immediately turns into water droplets – a process known as cold bridging.

Polyamide thermal breaks

To negate the prospect of cold bridging occurring and to minimise the amount of heat lost from residential and commercial environments, thermal breaks have been adopted within the framework of industry leading rooflights to minimise the conduction of heat. The framework of Sunsquare’s fixed, walk-on and opening rooflights now feature polyamide insulating sections within the aluminium framework, acting as thermal breaks and a barrier between internal and external temperatures. The polyamide sections are designed to be fitted straight into the aluminium extrusion and rolled together to ensure a strong and durable structure whilst keeping the internal section of the aluminium framework separate from the external part.

Low-emissivity glass units and argon-filled cavities

With Sunsquare rooflight frameworks we also go one further by filling window cavities with argon gas to further improve internal insulation and prevent condensation affecting the unit. Furthermore, the frameworks are factory glazed with soft-coat low-emissivity insulating glass units which work by reflecting interior heat back into rooms below; helping property owners to reduce energy bills and the size of their carbon footprint.

Thermal bridging and Part L Building Regulations

Thermal breaks or bridging play an important role in ensuring new-builds and redeveloped properties meet Part L Building Regulations – regarding the conservation of fuel and power in new and existing dwellings – and the Code for Sustainable Homes. Buildings are required to meet minimum U-value levels of 2.00 (W/m²K) for rooflights, windows and doors as part of a new Target Fabric Energy Efficiency (TFEE) standard. This standard is designed to make new and existing buildings more energy efficient, minimising the amount of CO2 produced and protecting the wider environment for future generations.

A quick note for would-be buyers: beware of unscrupulous companies advertising so-called ‘thermally managed ’ products. Marketers can be tricky about finding ways to make you hand over your money, and ‘thermally managed’ is just one example of deceptive language being used to signal a level of quality that isn’t there. Remember: only products which utilise proper thermal breaks can provide energy efficiency up to contemporary standards.

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