GREEN LIVING

Proposed amendments to the NCC 2022 energy efficiency provisions

Dr Phillip Alviano Sustainability Advisor

On 1 February 2019, energy ministers agreed to the Trajectory for Low Energy Buildings, a national plan for Australia to set a trajectory towards zero energy (and carbon) ready buildings. This report focussed on improving new buildings. NCC 2022 is part of this body of work. After a major stringency increase for commercial buildings in NCC 2019, building ministers directed the ABCB to develop enhanced residential energy efficiency provisions informed by the former COAG Energy Council’s Trajectory for Low Energy Buildings policy. This work supports the Australian Government’s commitment under the Paris Agreement to reduce greenhouse gas emissions and the National Energy Productivity Plan. These policies all focus on the role that buildings play in reducing emissions, improving energy productivity, reducing household energy bills, and helping to transition to the greater use of renewable energy and zero-emission vehicles. Below is an overview of the major changes that will be implemented in the NCC 2022.

Summary of major changes

Stringency increase the Star Rating Measure Increase thermal performance from the current level, equivalent to 6 Star NatHERS, to the equivalent of 7 Stars. What’s likely to be involved? Higher window and glazing performance. Increases in ceiling and wall insulation R-values. Restrictions on wall and roof colours. Changes to structural floor systems (insulated slabs or sub-floor insulation. Whole of home energy use requirements added As well as meeting the 7-Star requirement, new houses and single occupancy units (SOU) will need to meet a collective energy use budget for heating and cooling systems, hot water, lighting and swimming pool and spa pumps (where fitted). Measure Whole of home annual energy use requirements. Differences between Class 1 and Class 2 buildings. What’s likely to be involved? Introduction of a collective energy use budget for; • Air conditioning and heating systems. • Hot water systems. • Lighting. • Swimming pool and spa pumps. Ability to trade between the efficiency of systems for annual energy use budget. Onsite renewables may be installed to offset the energy consumption of the equipment but not the building fabric. The ABCB will provide a simple whole-of-home calculator to assist in quickly determining the requirements. The NatHERS Administrator is also expanding NatHERS beyond thermal comfort to incorporate whole-of-home requirements to align with the proposed NCC 2022 provisions. This will allow the whole-home assessment to be completed as part of the energy rating. New deemed to satisfy elemental provisions (Class 2) Measure New set of measures deemed to satisfy introductory provisions for Class 2 buildings. What’s likely to be involved? • The whole of the apartment building will need to achieve an average 7-Stars with no apartment permitted to be less than 6-Stars (under

NCC 2019 6-Star average and no apartment less than 5-Stars. • Developing new elemental DTS provisions for Class 2 buildings set at 7-Star equivalence (this will provide a second pathway for apartments to verify compliance after this option was removed in NCC 2010). • Developing a new verification using the reference building method for

Class 2 buildings. • Introducing new requirements for thermal bridging and steel framing. Note, the thermal bridging mitigation measures proposed for NCC 2022 do not seek to eliminate thermal bridging by all framing. Instead, it proposes to reduce the thermal bridging of steel frames, so the total R-Value of an element with steel framing is: • • No less than 95 per cent of that for a timber-framed element for insulation R-Values of R3.0 or less. • • No less than 90 per cent of that for a timber-framed element for insulation R-Values above R3.0. This differential approach reflects the diminishing returns of insulation at higher R-Values. Retrofit onsite renewables & vehicle charging Measure New provisions designed to allow easy retrofit of onsite renewable and electric vehicle charging equipment for Class 2 to 9 Buildings. What’s likely to be involved? New provisions are designed for ‘solar ready’ zones for potential future electric vehicle charging equipment installation for Class 2 to 9 buildings. New provisions are being proposed to

enable Class 2 and 5 to 9 buildings to be easily retrofitted with DER. DER include photovoltaic (PV) panels, battery storage systems, and electric vehicles (EV). The changes are intended to “future proof” buildings for retrofitting onsite renewables, which in many instances are likely to become business-as-usual equipment for commercial buildings in future. The provisions do not require EV charging equipment but are designed to make it much easier to install such equipment as EVs become more common over coming decades. • Condensation management measures Enhanced condensation management provisions. NCC 2019 introduced specific condensation management. For NCC 2019, more substantive measures are being proposed. What’s likely to be involved? Changes to wall sarking requirements to more vapour permeable types equivalent to Class 3 or 4 membranes (depending on the climate zones). Ventilating roof spaces that include; • Providing air spaces for roofs. • Changes to roof sarking installation and roof sarking vapour permeability requirements. • Additional roof space ventilation via the installation of whirlybirds, ridge or eave vents or similar. Notes: • Changes to sarking requirements for

Climate zone 4 to 8. Plus: Measure Enhanced condensation management provisions. What’s likely to be involved? Exhaust system changes include; Minimum flow rates for exhaust fans. Mandatory exhaust and ducting to the outside for exhaust fans and range hoods. Banning recirculating range hoods. Bathrooms not naturally ventilated must have exhaust fans with a 10-minute runoff timer and, Additional provision for ventilation to laundries/bathrooms containing a dryer. Conclusion

What will this mean in practice? Master Builders Victoria is currently organising NatHERS modelling for some housing designs to provide further information and evidence for members on the changes. From previous discussions with builders and energy raters, MBV believes the following is likely. • Aspect is vital: • Get the passive solar design correct from the beginning. • Look for living areas and windows on the north side of the house. Reduce window sizes elsewhere. • For further information on Passive

Solar Design principles, visit

Master Builders Victoria’s YouTube page. https://www.youtube.com/ watch?v=YylmeMilok8 • It will be easier to achieve 7-Star in single-storey houses rather than double storey. • Overshadowing by neighbours can reduce the star rating by 0.5. • Maximum insulation (R6 ceiling. 2.5 walls). • Most likely, all windows and doors in conditioned areas will need to be double glazed and thermally broken. • Plus, low-e glass for double storey. MBV understands the benefits of moving to 7-Star; however, we are concerned that wider implications have not been fully considered, and we continue to work with the government on these issues. They include. • An increased risk of condensation and mould. • A rigid assessment pathway. • Planning and lot layout requirements are not yet part of planning schemes. • A rushed and late consultation process and • industry upheaval, and supply chain shortages. As well as supply shortages, the industry has currently been hit by a tsunami of changes that are severely impacting construction: • New accessible housing requirements will add to high costs. • Supply shortages are increasing

the costs of products with price increases of 30-50 per cent. • Changes to trade registration requirements and, • The impact of COVID-19 on the industry, especially the renovation industry in Victoria and the risk of increased insolvencies in early 2022. MBV believes a significant transition period of a minimum of 2-3 years is required before new regulations take effect. This will provide time for; 1. The development of training and education for industry and consumers. For example; • The development of and support the industry’s training around condensation management issues and correct building techniques. • The development of housing displays showcasing 7 Star houses. • Allowing materials suppliers time to source and develop the window market, building membranes and product specifications and guidance. 2.Regulatory change to occur at an appropriate pace. For example; • Time for proper assessment of the changes and feedback through the

RIS process. • Inclusion of condensation management upgrades to the NCC. • Planning changes for new developments require improved lot layout for solar access and reduced overshadowing.