Major updates in effect from May 1 aim to increase energy efficiency by 30 per cent
The National Construction Code (NCC) changes introduced in May 2019 will come into full effect on 1 May 2020. The changes are aimed at making buildings more energy efficient and include key metrics for performance requirements. According to Energy Action, the new NCC means buildings could become 30 per cent more energy efficient while being cheaper to build.
The building sector is one of the fastest-growing end-use sources of greenhouse gas emissions. One of the most direct and effective ways to address this is to make buildings more energy efficient. Therefore, the transformational changes laid out in the NCC represent a significant opportunity to reduce greenhouse gas emissions in Australia.
While it is possible to retrofit buildings with energy-efficiency measures, it’s far cheaper and more effective to make buildings energy efficient during the design and construction phase. This puts the onus on architects and designers to specify the materials that will offer the best energy efficiency, and to make those specifications stick so that contractors aren’t tempted to substitute cheaper, inferior products.
Nick Brown, Technical Director Australasia & SE Asia – Kingspan Insulated Panels, said, “Specifications are an incredibly important part of any construction project. When contractors substitute products, they run the risk of creating safety issues and performance problems, and impacting the building’s longevity. Project leads should ensure that contractors understand that the products specified are non-negotiable and not interchangeable. This means including prescriptive and proprietary specifications that give contractors more detail and direction on what products to use.”
Using the right products, as specified by the architectural team, can be the difference between complying with the NCC requirements or failing to comply.
One of the benefits of changes to the NCC is that the deemed-to-satisfy (DtS) requirements are both simpler and more stringent. For example, in the previous version of the code, wall and glazing requirements were treated separately. The revised NCC combines the wall-glazing system calculation to consider different window-to-wall ratios and facade elements that will impact on the amount of solar radiation transferred into the building.
The revised NCC also requires the effects of thermal bridging to be fully accounted for in thermal computations. Compliance using traditional batts requires a much thicker footprint of up to 60 mm extra, which can have a significant effect on designs.
Testing is also more stringent. Previously, foil-faced laminated products had to be tested but only in their intended application. This meant products could be tested only on the ceiling, for example, even though they might also be used on the walls. Now, these products must be tested in both walls and ceilings or else they won’t be compliant. This may rule out some previously-compliant products that were tested successfully in one application but don’t meet the requirements for the other application.
The building envelope will also become more important. The new NCC includes metrics for how well-sealed a building is, which means how much air can enter through gaps and cracks. This could be managed via a pressurisation or blower door method with the metrics depending on the climate zone the building is in. Having an effective solution to manage the building envelope sealing will be crucial for compliance with the NCC.
There are two new verification methods to determine whether a building is compliant with the NCC: NABERS; and a Green Star Design & As Built rating.
The NABERS assessment is typically undertaken once the building is operational, 75 per cent occupied, and with 12 months’ worth of utility bills. The developer must sign a contract to design, build, and commission the building to achieve a target rating. This requires completion of an energy model to estimate total energy consumption. The model must be reviewed by an independent design review panel to provide third-party verification.
The Green Star benchmark is at least five per cent more stringent than the NCC DtS requirements, and a 10 per cent improvement is required on the reference building’s greenhouse gas emissions when undertaking the reference building pathway. This means that organisations that achieve the appropriate Green Star certifications will automatically meet the NCC requirements as set out in Section J.
How Kingspan Insulated Panels can help meet NCC requirements
Kingspan Insulated Panels aims to accelerate a net zero emissions future with the wellbeing of people and planet at its heart. Kingspan’s manufacturing facility in Melbourne is the first six-star Green Star-rated manufacturing facility in Australia, aiming to support production entirely through renewable energy.
The energy efficiency aims of the NCC, therefore, closely align with Kingspan’s values. As well as being more sustainable and less environmentally-damaging to manufacture, Kingspan’s products actively help meet the NCC requirements.
Addressing the building envelope, Kingspan insulated roof and wall panels are engineered to minimise air leakage. This provides for lower cost and more efficient HVAC plant design and reduces energy usage and carbon emissions. They also offer exceptional insulation performance guaranteed for 25 years and, due to the sandwich panel construction, do not include any thermal bridging.
Kingspan works with architects and provides free training to installers to ensure air tightness is achieved at building junctions. When installed correctly, the Kingspan system guarantees an air tightness of at least 3m3/h/m2. This is a markedly better than the NCC air sealing requirement of less than 10m3/h/m2.
Offering a single component system, Kingspan insulated panel systems create a weather-tight envelope faster and don’t degrade over the building’s lifetime.
As a single-component system, these panels also overcome the issue of thermal bridging, which is specifically addressed in the new NCC. Kingspan Panels avoid the effects of thermal bridging and insulation compression through their closed-cell core. The core is made from dense foam that provides continuous insulation and does not compress like a typical insulation blanket used in conventional built-up construction. This results in a higher R-value, helping achieve greater energy efficiency and increasing the level of comfort for occupants. This means thermal breaks are also not required when installing Kingspan Panels over metallic supports.
Kingspan roof panels are suitable for rooftop solar panel systems without through fixing. The panels can also be provided in a range of Colorbond® finishes, which lets architects and designers choose a colour with low solar absorptance, which should not be higher than 0.45 to comply with DtS provisions for most climate zones.
When it comes to wall panels, even Kingspan’s thinnest wall panel over-complies with the NCC requirements for most Australian climate zones, where the wall area is 80 per cent or more of the wall-glazing construction area.
When assessing compliance according to Green Star ratings, Kingspan Insulated Panels perform exceptionally well:
- Green Star Credit 14 Thermal Comfort: the effective heat barrier manages extreme internal and external differentials, leading to a higher level of comfort compared with conventional roof systems.
- Green Star Credit 15 Greenhouse Gas Emissions: the envelope-first approach means Kingspan Insulated Panels improve the skin of the building to achieve its best performance passively, reducing the need of oversized conditioning systems, and their energy requirements and emissions.
- Green Star Credit 19 Life Cycle Impacts: Kingspan Insulated Panels are transparent as a modular element that can be easily installed, have a life performance of 40+ years with no depreciation over time, and can be easily dismantled for reuse or recycling.
- Green Star Credit 21: Sustainable Products: Australian manufactured, most Kingspan panels have been assessed with Environmental Product Declarations (EPD), including the product’s Life Cycle Assessment (LCA), which show the product’s transparency and sustainability. This allows specifiers to easily earn points for both the Green Building Councils of Australia and New Zealand under the Green Star programs for credits as sustainable products.
To find out more about how Kingspan Insulated Panels can help meet the new, stringent requirements in the NCC, contact us today.