Achieving Thermal Efficiency on Balconies

How can I achieve thermal efficiency?

What considerations are there for designing balconies with thermal efficiency?

Firstly it is essential to always remember that thermal performance requirements need holistic consideration, not just individual component Thermal Efficiency performance assessed in isolation. For example, an incredibly efficient balcony connection anchor cast into a building with poor thermal performance in the rest of the building envelope is unlikely to achieve the desired performance for the whole building. It is, however, likely to be at the expense of structural performance, which can often be the cause for the perception of bouncy balconies, which is common in the market place at large.

Bracket options include cast-in anchors which incorporate a thermal break, such as ‘off-the-shelf’ products from specialist suppliers. Alternatively, specialist low-conductivity materials can be used (e.g. PTFE or similar high strength plastics), all of which would normally be used with stainless steel fixings (due to stainless steel having a much lower thermal conductivity to mild steel). Ensure all components with a thermal role work synergistically whilst getting a balance between thermal and structural performance.

The combustible cladding ban, effective from 21st December 2018, also has an impact in regards to the materials which may be used on the exterior of buildings over 18 metres.

What can be learnt from Sapphire’s experience?

We have experience with many proprietary systems and have conducted our own research and testing, so you don’t have to spend time and money inventing a thermal break solution from scratch.

We have explored the principles, and analysed our own balcony anchors and thermal breaks, with multiple thermal specialists including Oxford Brookes University. The objective was to maximise thermal efficiency whilst maintaining the best structural performance. The key learnings from these are:

1. The configuration and location of the thermal break relative to floors and ceilings can make a significant difference to heat loss as the transfer of heat will often be through these areas which tend to be less insulated than the thermal break material.
2. The chosen insulation materials used to form the thermal break often doesn’t make a significant difference to the overall thermal performance of the building. Architects should, therefore, consider good ceiling and flooring insulation around such junctions.

In the interest of improved thermal efficiency whilst providing a fire stop around the anchor penetration, we are happy to offer the Sapphire StubGuard as an option on your project. Get in touch for more details.

If you are interested in understanding more about the thermal performance correlation with the rigidity of your balcony there is a further whitepaper available from Farrat found here.